kimchi & kraut

Passive House + Net Zero Energy + Permaculture Yard

Tag Archives: green building

Urban Rustic: Main Bedroom and Bathroom

0

Design Elements

To create a warm, inviting bedroom and bathroom we knew we wanted to incorporate the same basic Urban Rustic design elements that we intended to use throughout the house. At their most basic level, these elements include wood, metal, and concrete (or stone). These show up at the largest scale in our hickory wood floors, our ‘stained’ concrete porcelain tiles, and our quartz countertops (kitchen and bathrooms). On a much smaller scale, these elements show up in variety of decorative objects that we have carefully curated, placing them throughout the house.

The overarching goal was a mix of sleek and modern with aged but beautifully worn. Whether for the exterior or the interior, the visual cues were rooted in a motif of early 20th century artisan workshop and small farmhouse.

“Successful modern reinterpretations of traditional architectural styles move us not only at an aesthetic level. They show us how we, too, might straddle eras and countries, holding on to our own precedents and regions while drawing on the modern and the universal… Without patronising the history they profess to love, they show us how we, too, might carry the valuable parts of the past and the local into a restless global future… [succeeding] in succumbing neither to nostalgia nor to amnesia.”

— Alain de Botton, The Architecture of Happiness

On the exterior this is achieved with a blend of black charred cedar, or shou sugi ban (aka yakisuki), and a restrained use of natural cedar highlights:

The rustic siding and overhangs are then complemented by the modern, sleek, metallic windows, doors, and even the gutters and downspouts. These visually heavy, and mostly dark, elements play well with the surrounding landscape: in summer, contrasting with the vibrant green vegetation and bold flower colors; in winter, our black box stands out in the surrounding white blanket of snow.

Heading indoors, we knew we wanted to experience the inverse of what we established on the exterior.

“… the balance we approve of in architecture… alludes to a state that, on a psychological level, we can describe as mental health or happiness. Like buildings, we, too, contain opposites which can be more or less successfully handled… we instinctively recognize that our well-being depends on our being able both to accommodate and to cancel out our polarities… Our attempts to harmonise our different aspects isn’t generally helped by the world around us, which tends to emphasise a range of awkward antitheses. Consider, for instance, the truisms which hold that one cannot be at the same time both funny and serious, democratic and refined, cosmopolitan and rural, practical and elegant, or masculine and delicate.

Balanced buildings beg to differ.”

— Alain de Botton, The Architecture of Happiness

Where the black siding absorbs sunlight, creating a brooding, deeply rooted in place black box, for the interior we wanted to make sure we flipped this dynamic, with a mostly neutral baseline, allowing us to then accent this bright and light foundation with vibrant pops of color. Where the exterior is dark and bold, we wanted the interior to be light-filled, warm, and inviting.

As a backdrop, we went with clean white ceilings and basic painted wood trim details. With light gray walls as a neutral canvas, it allowed us to play around with colors and textures, both for artwork and in terms of furniture or decorative objects. With this basic palette of colors and materials, we knew that the bold artwork that we wanted for our walls would really pop and have a long lasting visual vibrancy over the widest possible range of the color spectrum.

Going with basic painted white trim also meant we could contain costs while also keeping the main focus on decorative elements like flooring, wall art, and miscellaneous decorative objects.

For the baseboard, we went with 1×6 poplar, which we had used previously in our last house:

Around exterior doors and windows we chose to utilize drywall returns rather than more elaborate wood trim details. The exception was for our window stools. Here, we went with 8/4 poplar. The thicker material goes well with the chunky profile of our passive house doors and window sashes, particularly noticeable when the units are open.

Below, testing out a piece of the poplar stool in our Pantry-Laundry Room, trying to figure out how far beyond the window opening to go with the horns:

To create a more rustic, informal look, in addition to the thickness of the material, saw marks on the outside edge were mostly left unsanded. The face of each stool was given a gentle, rounded-over edge by hand, while being careful to sand — only minimally — on and around the surface of the saw marks.

Even though I was a little worried about not sanding this face sufficiently, it turned out that we ended up with a nice balance. In the right light, typically morning or afternoon raking sunlight, the saw marks are evident, even prominent, through the layers of primer and paint, offering up interesting shadow lines. At other times of the day, or under the glow of artificial light at night, these saw marks mostly disappear:

Opting to forego an apron trim piece below the stool we felt produced a simpler, cleaner look, although it did require some drywall patching below each rough window opening to more easily close the gap between stool and drywall with a high quality caulk.

We wanted the visual heft of the stools to stand on their own. Using any style of apron may have softened the look we were going for. The downside to a more minimal look, of course, is that there are fewer places to hide imperfections.

We really like the balance between the more formal white paint and the size and texture of the stool itself.

Main Bedroom

In the bedroom and bathroom we started with a white ceiling, white trim, and gray walls. Instead of using an accent wall, we opted for ‘blocks’ of color on two walls, on display upon entering the bedroom:

A dark, rich gray for the headboard wall is offset with a barn red for the long wall that connects the bedroom to the bathroom. To keep the space feeling as open as possible, we opted to go without doors for the bathroom or the walk-in closet. We realized this was an option based on our last home where these two doors were never used, remaining in the open position for the ten years we lived there.

Below, the point where bedroom meets bathroom, and where the richness of the color palette is fully realized:

The combination of ‘weathered concrete’ porcelain tile with the warmth of the hickory mimics the contrast between dark, cool gray and rich red on the adjacent walls.

The same area, looking up towards the ceiling:

With the paint and trim complete, we could finally get some artwork on the walls. We decided to give away most of our wall art from our previous house to family and friends. This allowed us to personalize our new home, particularly since we were opting for a DIY-heavy approach. It also meant our daughter could be involved in anything new that we created.

Below, this framed reproduction of Magritte’s ‘Empire of Light‘ is one of the few items that carried over into our new house:

Note the thickness of the profile on the open window sash with the thickness of the previously mentioned window stool:

A significant percentage of our construction budget went to Passive House details like air sealing, insulation above building code minimums, an ERV, and high performance windows and doors, not to mention our solar panels. Consequently, when it came to interior design, we were happy to commit to a DIY approach:

Apart from any potential savings compared to items bought off-the-shelf, we also find it more fun and rewarding to come up with our own bespoke self-designed handmade items. We’ve also found that custom made items tend to endure and stick around far longer than mass produced items, regardless of their price tag (typically both in terms of durability and enduring affection).

“‘Decor’ and the conception of ‘interior design’ have spread so widely, that very often people forget their instinct for the things they really want to keep around them… people have begun to look outward, to others, and over their shoulders… and have replaced their natural instinctive decorations with the things which they believe will please and impress their visitors… [Decor] is most beautiful when it comes straight from your life — the things you care for, the things that tell your story.”

— Christopher Alexander, et al., A Pattern Language

For the bookend space to the left of our bedroom window we used a rust technique on some sheet metal. In a bath of white vinegar, hydrogen peroxide, and salt, we soaked each piece of metal until we achieved the heavily scarred surface we were aiming for:

There is some latitude in controlling this chemical reaction as the metal rusts. Minimizing the time of exposure can allow some of the original bare metal color to remain. With a longer soak, and some brushing of the liquid repeatedly over the surface of the metal, a much deeper, all-encompassing level of damage can be achieved.

This sample, pictured below, shows a blend of rust and bare metal, prior to being sealed:

After the rusted steel sheets had a chance to dry, we used a low VOC sealer from AFM Safecoat to bind the rust and prevent any ongoing ‘dusting’ (similar to the strategy we employed using tung oil on our charred cedar).

The four individual panels were then mounted on a sheet of plywood. The plywood had been attached to 2×4’s, making it simple to hang the piece on the wall:

The white letters were painted on prior to the seal coat because I wanted some of the rust to bleed through the paint for a more weathered effect to match the level of rust:

To maximize the overall bare-bones look, the 2×4’s and plywood, clearly visible on the sides, was left fully exposed:

The phrase itself is from The Doors song ‘When the Music’s Over’, part of which has an environmental message that blends well with our rock ‘n’ roll theme.

With our blue porcelain frog sticking to the window header, our vignette with a nature theme is mostly complete, framing the view to our backyard, which, at this point, was still little more than a mulched moonscape.

Mid-morning, in the photo above, with sun entering through the open doorway from the left (south).

The authors of A Pattern Language strongly advocate for east-facing main bedrooms:

“The sun warms you, increases the light, gently nudges you to wake up — but in a way that is so gentle, that you will still actually wake up at the moment which serves you best…”

— Christopher Alexander, et al., A Pattern Language

Below, the sun just before the winter solstice, almost reaching directly into the bedroom (just over 16′ from the south-facing windows). This was part of our passive solar strategy for the house:

Although our bedroom technically faces west, because of the size of our bedroom and family room windows (4.5′ x 9′), and the oversized door opening to the family room that faces south, we end up with a flood of morning light regardless. The intensity of the light is far less than direct east-facing, but the overall effect is similar. On paper this shouldn’t really work, but reality shows otherwise. Something to consider for those in the design stage of their own build.

The next project for the bedroom was to add some seating below the window.

To get started, we picked up some reclaimed lumber from Meeghan, at her shop Great Lakes Yard.

The piece on the left, below, has been epoxied and sanded, ready for its final clear coat. The piece on the right, destined for the family room, is finished, waiting for legs to be attached.

The epoxy was serving both decorative and structural functions. These pieces, particularly the one on the left, were in pretty bad shape in terms of structural integrity. The epoxy was filling cracks, crevices, and also allowed me to rebuild some of the badly damaged outside edges. We chose a blue metallic pigment since it offers an almost water-like iridescence.

Building up some of the outside edges not only added to the visual effect, it also helped stabilize what would’ve otherwise been a piece on the verge of falling apart. This section of wood was a structural framing component during its working life. I left some of the larger holes empty (these look like they were for conduit), while concentrating on the smaller voids. In addition, the mortise pockets benefited from some of the blue epoxy, giving these areas a look of pooling water while also making these spots easier to dust and keep clean:

The built-up outside edges have a nice shimmering water look to them:

Some doubled up 2×6’s painted black with some nice metal hardware completes the look. The original level of wear in the piece can be read in the front vertical face as it changes in thickness from one end to the other.

Having large windows in the bedroom makes a bench like this ideal for a quick sit to take in the evolving flow of life in the backyard as the seasons develop and change. The rest of the time it’s a structural framing member that has been transformed into what we hope is a deceptively unique decorative object:

For our new dresser we decided to go full-on rustic with reclaimed wood and vintage fruit label drawer pulls. The warm wood tones help balance the fiery red accent wall while echoing the color variation in our hickory floors. The aged wood would also serve as a warm, neutral backdrop, helping to put emphasis on the pieces that would soon sit atop the dresser.

My daughter helped me apply tung oil to the ‘box’ and the drawers, giving the dresser a warm, natural matte finish. After a final sand and wipe down, the tung oil brings the old, dry looking wood grain back to life:

Whether it’s searching for interesting reclaimed items or just unique decor touches, I’ve had better luck looking online than with brick and mortar stores. After trying several locations in the Chicago area, as well as various shops when we’ve been out of town, I always come back to shopping online, largely because the pool of options is so much greater than at any one store. We’ve gotten lucky buying a couple of items locally, but the overwhelming majority of what we purchased came from online shops.

Although time consuming, browsing sources like Etsy almost always proved more fruitful in the end.

In the case of the drawer pulls, I found these vintage fruit label ones on Etsy:

Even when it comes to having items framed, we had better luck developing our own technique than using the more traditional frame (wood or metal) with glass approach.

We start by mounting the image to some smooth plywood that’s been previously sanded and dusted. We mount the image using a spray on adhesive. As the glue sets up, we do our best to squeegee out any air to ensure good contact between the plywood and the photo. Once the glue has fully dried, we do an epoxy pour, a flood coat, allowing it to spread over the entire surface, including falling over the edges.

With the initial pour allowed to dry for a couple of days, if a high-gloss finish isn’t ideal, I then sand the epoxy before applying a hardwax oil coating of Osmo Polyx, typically in a satin finish, although the matte finish makes for a nice, subtle velvet-like finish as well.

This technique is roughly the same deployed for river tables, or any project with wood, epoxy, or wood-epoxy combination:

In our case, to experiment with this technique we started small, with a Blondie and Pat Benatar concert poster, before moving on to much larger images:

The trickiest part is making absolutely sure the outside edges of the image are fully adhered to the plywood. If not, when the flood coat of epoxy is applied you risk having the image lift, which is virtually impossible to fix after the epoxy has been poured.

For our red accent wall I decided to use an image of our daughter playing on the Chicago lakefront at sunset. The rich blues in the failing light accentuate the water theme I was after:

In addition to the image, we added a slightly tongue in cheek family altar with a small slab of decorative white concrete as its base.

Below, afternoon sun breaking across the photo and the red accent wall:

For our headboard wall we started with a print by Nikki McClure. We really enjoy the playful vibrancy in her work. The print was mounted and finished with epoxy and then the Osmo as outlined above.

With a base frame made of 1×4 furring strips, I attached the print and then surrounded it with additional 1×4 furring strips to create the finished surface:

Using the furring strips was in keeping with our Urban Rustic design goals, in this case utilizing underappreciated framing materials to show off their inherent beauty and utility in a new context.

After completing a light sanding, trying to hold onto the grading stamps as much as possible, I then whitewashed the 1×4’s to complete the rustic look. The goal was a weathered look:

This was amplified by using the Osmo to seal-in the whitewash since it adds a slight amber, or yellowing, to the surface of the wood, increasing the aged effect. It was a relatively light whitewash application, which allowed some of the original wood color to come through the final finish:

For my nightstand I started with 1/2″ Purebond plywood for the carcass. The dimensions are larger than what’s typical, but I wanted it to look short and hefty.

I made deep drawers, using Blum drawer slides to help support the weight of anything put in the drawers, especially books. We used them for our kitchen drawers and we love the smooth function and soft close function. They’re not the cheapest option, but their quality is hard to match.

I wrapped the carcass with 1×4 furring strips, just like the headboard piece, and then used 1/2″ plywood for the drawer fronts, painted a vibrant red to match our red accent wall. Both the carcass and the drawer fronts were sealed with the Osmo.

The black drawer pulls I found online. I didn’t try to refinish them, instead I just applied a couple coats of sealer to prevent further rusting. I then attached them to the drawer fronts with some lag bolts. This combination epitomizes the Urban Rustic aesthetic: sleek, modern red and shiny steel with rusted, worn and peeling hardware.

For the top I glued two sheets of 3/4″ Purebond plywood together for a chunkier look, using Timbermate putty to fill and smooth out the exposed edges.

With a slightly rounded over edge created using a router, it was time to have some fun applying stickers. Starting with a Vespa Italian roundel and striping, my daughter and I added various other famous high-performance Italian industrial design brands, partly inspired by the work of Bruno Munari.

As with the wall art photos, first we did an epoxy flood coat before sanding and applying a final couple coats of Osmo satin, which produces a nice combination of hard-wearing with a subtle shine.

The stickers were a fun homage to high Italian industrial design:

The little tank of a nightstand is a nice mix of urban and rustic elements:

For my wife’s nightstand I started with a mini river table.

With the mold complete, I could get the two pieces of walnut in position to better evaluate what would be the final look:

I thought about using a white metallic epoxy, but anytime I’ve used a white pigment with epoxy it’s always yellowed to one extreme or another over time (typically within the first year). Instead, I opted for a metallic black, which also had some metallic silver mixed in.

Opinions vary on the enduring charm of river tables, but it’s probably a safe bet that a more subdued pigment choice, like black, will have a better chance of being appreciated and loved well into the future.

Below, the black epoxy complete, and the planing mostly done:

Below, after sanding, routing the edges, and an initial coat of Rubio Monocoat:

Below, after a second coat of Rubio has been done. Although it belies the name, I usually end up with better results after a light sand and a second coat of Rubio has been applied:

I’m hoping the variation in color tone doesn’t mellow too much with age. The stark contrast between light and dark woodgrain adds to the beauty of these pieces.

Close-up of the walnut surface:

The wide color variation is incredibly beautiful. Moreover, the black epoxy adds to the wave effect visible in the woodgrain, reminiscent of flowing water.

For the body of the nightstand I used the Purebond plywood for the carcass, leaving it exposed as the final finish for the sides. In combination with the face frame, I opted for inset drawer fronts, painting them gray to match the headboard wall color. The pulls are actually dock cleats, offering a heavy-duty look for a component that’s usually more delicate in appearance.

Like the ‘Mother’ wall art piece, I used a whitewash finish on the face frame and the sides, sealed once again with Osmo. I used the Blum slides for the drawers.

Below, the nightstand complete:

Main Bathroom

Design for our bathroom started with our floating vanity, which is accented with a combination of charred cedar and lag bolts, and completed by the quartz counters and the porcelain vessel sinks. This combination reflects our Urban Rustic building blocks of wood-metal-stone.

In addition, along with the toilet paper holder, it gave us an opportunity to bring the charred cedar indoors. We would do this with several decorative elements throughout the main floor, using the charred cedar as an accent rather than as a main feature like it is on our exterior.

With oversized subway tile and red glass accents, the shower plays well with the more rustic and handmade items in the space.

The bright yellow painting references lines from a Pixies song:

Struggling to find a unique toilet paper holder, I came across this one on Etsy: Wrench

This well-worn industrial sign adds a whimsical touch:

The toilet paper storage box works well in terms of function, and the charred finish adds some nice color and texture:

For the red accent wall I wanted a piece that would start in the bedroom and carry through to the bathroom, where only then it would reveal its dramatic punch.

It also makes for a nice companion piece to the ‘Mother’ headboard wall art:

As with the ‘Mother’ piece, I tried to hold onto the lumber stamps as much as possible. I also tried to select the individual pieces of 1×4 for their color, wood grain, and knot pattern. This was more important for this piece since it was left ‘natural’, with only a couple coats of Osmo for some protection and for a slight ambering effect. The natural tones of the wood and the inky black in the artwork make for a nice combination with the intensity of the red on the wall:

We picked up this second Nikki McClure print from Anthology in Madison, Wisconsin, a cute shop with a nice range of products. My wife and daughter, along with some extended family, love going here every time we’re in Madison.

Despite their many imperfections, the 1×4 furring strips make for a unique, rustic decorative touch. On a job site they don’t get much respect, typically kept hidden behind finished surfaces like siding in the case of a ventilated rainscreen.

It’s been fun devising ways to let them shine in their own right.

Sunlight from the west, entering the bathroom around midday:

In addition to the building science we incorporated into the structure of our build, collecting and executing the design elements for our interiors has made crafting and building our own home one of the most rewarding experiences of our lives.

“When the objects we use every day and the surroundings we live in have become in themselves a work of art, then we shall be able to say that we have achieved a balanced life.”

— Bruno Munari, Design as Art

Permaculture: The First Two Years

0

Observe and Change

Growing up, my parents always had a garden plot of vegetables in our backyard. Pulling weeds in the hot sun is my strongest childhood memory of these gardens. Needless to say, the memory is unpleasant. Growing vegetables seemed like a sweaty, tiresome chore. More to the point, it seemed entirely unnecessary since we had so many grocery stores in our area.

It was only many years later, after living in our first house for awhile, that an interest in plants, of any kind, was sparked. My wife and I were living in a fairly standard suburban tract-home subdivision. Most of our neighbors had foundation plantings around their homes; some even had additional flower beds carved out of their well-kept lawns, although these were the exception. Apart from these plantings up close to each home, the subdivision was almost entirely a repeating pattern of roads, homes, and then their individual patch of green lawn.

In an effort to improve our curb appeal (we had zero plantings and only lawn grass), we started with some basic perennials like ornamental grasses, flowers, and some small shrubs around the front entry.

After realizing how much fun it was to plan out and arrange these plants, the border edging, and even the shape of the borders themselves, each subsequent spring meant carving up more patches of lawn in order to develop our plant varieties and combinations.

It was during this period that I began reading Mother Earth News, Fine Gardening, and ordering online from suppliers like Seed Savers Exchange and Johnny’s Seeds.

After starting out copying what I had seen my parents do — using store-bought chemical fertilizers and pesticides to manage plant health — we quickly moved in the direction of organic solutions. Not only were they less dangerous to handle, they were also less detrimental to the overall soil food web.

“Think of scooping up a handful of soil and leaf litter and spreading it out on a white ground cloth, in the manner of the field biologist, for close examination. This unprepossessing lump contains more order and richness of structure, and particularity of history, than the entire surfaces of all other (lifeless) planets. It is a miniature wilderness that can take almost forever to explore.”

— Edward O. Wilson, Biophilia

Initially viewing the soil in our yard as a lifeless medium requiring endless varieties of supplements in order to achieve the results we were looking for, as I read and learned more, we began to focus on the soil as our main building block for everything we wanted (vegetables, shrubs, flowers — even a healthy lawn).

In fact, an early prod to trying something unconventional occured after realizing our lawn care service had only one solution to every problem that cropped up in the yard: using either larger quantities of chemicals, or just different varieties of chemicals. There wasn’t any concern for site conditions or causes; the only emphasis was on treating symptoms, namely, weeds.

“… how chemical companies have always handled the problem of pest resistance: by simply introducing a new and improved pesticide every few years. With any luck, the effectiveness of the last one will expire around the same time its patent does.”

— Michael Pollan, The Botany of Desire

At some point, after we had a couple of growing seasons with mixed results, I came across Masanobu Fukuoka’s The One Straw Revolution and Toby Hemenway’s Gaia’s Garden. Each, in their distinctive way, advocated for a ‘nature first’ approach when gardening or farming, emphasizing the importance of setting up structures and plant relationships that would allow nature, over time, to do most of the work for us.

“Nature, left alone, is in perfect balance. Harmful insects and plant diseases are always present, but do not occur in nature to an extent which requires the use of poisonous chemicals. The sensible approach to disease and insect control is to grow sturdy crops in a healthy environment.”

— Masanobu Fukuoka, The One Straw Revolution

After my daughter was born, and my wife grew tired of her hour-long commute, we decided to sell our home and move closer to her work. By that time I had also learned about Passive House and Pretty Good House, in addition to Susanka’s Not So Big House series of books — homebuilding design strategies that were defiantly moving away from conventional norms (not unlike Permaculture).

The more we thought about what we would want from our new home, the more this combination of Passive House and Permaculture design principles appealed to us.

Here’s one example of what can be done on a suburban lot:

In terms of the Permaculture, we knew we wanted to experiment more with growing our own food, to the extent that’s possible in our Climate Zone 5 region, here in the suburbs of Chicago. After trying to grow a whole host of veggies our first few years gardening — thumbing through any number of seed catalogs in winter became a favorite pastime — we slowly learned what we enjoyed growing and what we thought was more hassle than it was worth.

Here’s another example of what can be achieved in the suburbs:

Short of an end times scenario, in which every calorie we consume would first need to be harvested from our yard, we whittled a potential list of food options down to a workable number of herbs, fruits, and vegetables. With its focus on soil health, a side benefit of setting up a Permaculture-inspired landscape is that a patch of ornamental flowers or grasses can be quickly converted to food production, in most cases within a single season.

Although we were excited about trying new fruit varieties (whether in tree, shrub, or vine form), our main design goal was to be largely ornamental in focus — especially at first glance to any passerby, with food items woven in amongst the bold mix of colors and textures.

Permaculture is still a new idea in most parts of the US, so we felt more confident that our neighbors would be supportive so long as things looked ‘pretty’ for most of the year. We were also confident that, with the right mix of plants, we could welcome in the local wildlife, no matter the scope of our overall food production.

Here’s an example of what time plus significant acreage can produce:

Regardless of the name applied to its specific scale or form — Permaculture, Agroforestry, Edible Landscape, Food Forest, Regenerative Agriculture — we knew that our design would begin with a foundation of thick mulch (similar to the Ruth Stout method).

In addition to going lawn-free, here are some of the other main goals for our yard:

  • Avoid digging (e.g., no seasonal plowing of the soil for growing vegetables)
  • Avoid outside inputs; as much as possible, create a closed loop system
    • e.g., no synthetic fertilizers, herbicides, fungicides, or pesticides
  • Xeriscaping techniques
    • plant selection and placement based on water needs
      • limit plants that do require more water to those areas where water tends to sit, or else plant close to the house for easy, quick watering (e.g., dahlias)
    • leave no bare soil exposed
    • no dedicated irrigation system
      • occasionally hand water new plants for the first year until established
      • water vegetables, and flowers like dahlias, infrequently but deeply
      • use sprinklers only after prolonged period of drought and plants are visibly stressed
    • use thick base layer of mulch to retain moisture and even-out temperatures seasonally, in addition to building long-term soil health
    • encourage rainfall to stay on site and be absorbed rather than allow it to run-off
  • No waste
    • dedicated compost bin (for plant-based kitchen food waste)
    • compost or ‘chop and drop‘ cuttings in situ (e.g., Russian comfrey, shrub prunings, perennial cut-back in spring)
    • again, the goal is a mostly closed loop system
  • After getting soil and plant relationships established, mimic Fukuoka’s ‘do-nothing‘ approach

When confronted with a problem in my first years gardening, it’s easy to recall the immediate impulse to reach for a chemical solution, or to look online for a quick (typically industrial) fix of some kind. This knee-jerk reaction ebbed over time, particularly as I learned more and I experimented with natural or even ‘hands-off’ ways of reaching the same solution.

Many of the ideas associated with organic or Permaculture-based growing become obvious, even second nature, once they’ve been adopted and the subsequent positive results speak for themselves. Even so, it does take some time for this change in perspective to fully develop (again, the same is often said of Passive House building principles).

An anecdote from Sepp Holzer regarding voles illustrates this change in mindset — working with nature to get what you want, rather than engaging in a pitched battle of costly resistance:

“… If I fight them (with poison, gas or by catching them), the territory will only become free for others. The lower population density will be balanced out by more and more empty territories. Voles will produce more offspring or even just produce more males. Instead of catching, poisoning or gassing pests, it is better to consider the cycle of nature. If I let the voles work for me, I will have aerated, loose and well-drained soil and also lush, diverse vegetation. The vole will no longer appear as a cause of damage. Moreover, poisoning and gassing will contaminate the soil… The energy required to repair damage to the soil is much greater than the supposed damage caused by the voles eating crops. It is important to make sure that there are always enough decoy plants available to them… If there are enough available, the voles will leave the fruit trees alone. It is not a question of what I can do to fight the ‘pests’, but what can I do for them, so that they will not cause damage and even work to my benefit [emphasis added]. “

— Sepp Holzer, Permaculture: A Practical Guide to Small-Scale, Integrative Farming and Gardening

As Permaculture advocates are quick to point out, in many cases ‘the problem is the solution‘. This approach to problem solving requires imagination and a willingness to question assumptions while also thinking through potential unintended consequences. Far different from the normal way of doing things, rooted in a ‘better living through chemistry’ approach, one that assumes a fix must already exist, so it’s on a store shelf somewhere and you just need to find it.

Rather than attempt a deep dive on the science and design principles associated with Permaculture, what follows is more of an overview of our experience setting up the basic foundation and structures of our design, with commentary on what we find works and where issues have come up for us.

Please consult the many excellent resources outlined above for a more in-depth look at all the possible techniques and plant relationships, and how they can be organized to fit the scale of your own project (from patio to homestead).

For some additional options, go here: Resources

Getting Started

Our lot is roughly 60′ x 190′, so about a quarter of an acre. It was an infill lot that had been sitting idle since at least the subdivision was first developed.

Except for a single, large elm tree, with its open southern exposure the lot was mostly ideal for Passive House (e.g., passive solar heating and rooftop solar panels) and Permaculture design goals.

“We owe it to the fields that our houses will not be the inferiors of the virgin land they have replaced. We owe it to the worms and the trees that the buildings we cover them with will stand as promises of the highest and most intelligent kinds of happiness.”

Alain de Botton, The Architecture of Happiness

Unfortunately, the large elm tree needed to be removed since it would’ve been right outside what would become our kitchen door.

Thankfully, none of it went to waste. The mulch would be used up fast once we neared the end of construction and could begin to concentrate on landscaping. Even the larger logs, along with some additional logs donated by a neighbor after one of their trees fell down, would be kept towards the back of our lot. In this area they would serve as excellent mushroom food, a break between our yard and the utility easement, and a fun spot for my daughter to run and jump from log to log.

As far as soil conditions, after testing we learned it was ideal for our basement foundation. However, below the first 6-12″ it was predominantly clay.

“The great issues facing our environment — both locally and globally — are linked to the innumerable organisms that live underground. The health of our soils and gardens and fields have suffered from a dependence on chemical fertilizers and a lack of appreciation for the contribution to soil fertility of the myriad creatures that labor underground. Their interactions below ground result in a balance between the processes of growth and the processes of decay. The humus that these creatures generate during the processes of decay is essential to fuel the processes of growth. Without humus, mineral nutrients from fertilizers are soon lost from the soil, along with the pore spaces that hold the moisture and the air that make a well-structured soil so productive and fertile. Countless reciprocal interactions between life belowground and life aboveground shape the world in which we live.”

—James B. Nardi, Life in the Soil: A Guide for Naturalists and Gardeners

This became readily apparent once excavation began and the soil horizons were exposed:

Without much attention or care (apart from regular mowing), at least in the conventional sense, the lot had flourished without any chemical inputs or irrigation for years. Although not exclusively lawn grass, any number of ‘weeds’ were growing happily alongside one another in a thick, healthy green turf. Unfortunately, once construction began, much of this fertile top layer would end up being disturbed or damaged.

Design Plan for the Yard

A quick overview of conditions on our lot:

Our house runs mostly east-west along its longest axis. Even so, our north side, beginning in spring and going until fall, gets a significant amount of early and late afternoon sunlight.

In the backyard, which faces west, the neighbor’s imposing trees offer ample shading beginning around noon, before the sun breaks through once more, briefly, in the evening as the sun sets.

In terms of grading, most of the yard is sloped towards the north, although there’s a small section near the very back of the lot where the pitch reverses itself (thus, the far south-west corner is always the wettest section of our yard; here, water can collect and experience mostly shade conditions).

“Consider the site and its buildings as a single living eco-system… People always say to themselves, well, of course, we can always start another garden, build another trellis, put in another gravel path, put new crocuses in the new lawn, and the lizards will find some other pile of stones. But it just is not so. These simple things take years to grow — it isn’t all that easy to create them, just by wanting to. And everytime we disturb one of these precious details, it may take twenty years, a lifetime even, before some comparable details grow again from our small daily acts.”

— Christopher Alexander, et al., A Pattern Language

Once we purchased our lot and had some sense of the size of home we would be building, I could start planning the layout for Permaculture design ideas.

One of the first elements for our yard would be a deep mulch layer. While suppressing weeds, it could also help break up the clay just below the surface, while also improving drainage (soaking up large quantities of water like a sponge) as it slowly decomposes to make ‘black gold’ or compost (acting, essentially, as a slow release fertilizer).

In lieu of fencing, we thought a wide variety of shrubbery (height, width, color, and texture) along the southern edge of our property, with additional shrub layers to parts of the north and west, would be an excellent way to gain some privacy while also maintaining mostly open views. As these various shrubs matured, they could offer excellent shelter and nesting sites to birds in the area. One of our main defenses against insect pests would prove to be welcoming in the birds.

“… creating ideal conditions for wildlife by permitting fencerows to grow up, by the establishment of multiflora hedges, and even ‘islands’ of undergrowth or multiflora in pines in large open fields. Even the unpopular house sparrow makes a contribution in keeping down insect populations, a contribution far beyond that for which he is given credit… I have seen the house sparrow in our gardens stripping every green aphid from the roses…

The hedges, the birds, are merely a part of a general pattern based upon natural checks and balances in the operations of nature and have contributed enormously to the material welfare of Malabar Farms, as well as to the pleasure and beauty contributed by the hedges and by the presence and increase of bird life of every sort.”

— Louis Bromfield, From My Experience

These shrubs could also offer us some protection from wind once they mature. In effect, we would be setting up a fairly traditional hedgerow, with many of the same benefits enjoyed by pre-industrial farms.

Out at the street, a mix of perennials, flowers, grasses, ground covers, and smaller shrubs could handle some neglect away from the house, while also surviving winters covered by plowed snow and salted roads.

The north side of the driveway would be a mix of mostly shorter perennials, mainly chosen for their color and texture. Since this area would experience run-off from vehicles on the driveway, we thought it best to avoid growing any food here.

The remainder of the yard, meaning most of the front and back, could be used to grow a variety of food items, while also affording us the opportunity to play around with a wide range of plantings to boost visual interest and biological diversity.

The north side, we always assumed, would be a blank slate until most of the yard was started. As we experimented in other areas, we could incorporate what we learn on this side of the house.

Some of the ideas for our house and yard that were eventually dropped due to budget, time, or site specific constraints included composting toilets, a gray water system, and on-site water storage such as cisterns or above-ground tanks — ideas that are well worth exploring whenever possible.

“Our current ways of getting rid of sewage poison the great bodies of natural water, and rob the land around our buildings of the nutrients they need… Almost every step in modern sewage disposal is either wasteful, expensive, or dangerous.”

— Christopher Alexander, et al., A Pattern Language

As a basic overview, this framework would serve us well when the time came to begin purchasing and placing plants on site.

It was only as we headed towards the tail end of construction that we could even begin to address the site conditions in preparation of our Permaculture goals.

Since we wouldn’t be putting down grass seed or sod (going lawn-free was one of our earliest design goals), the first priority was to address water management, in particular those areas of the yard that were most under pressure from soil erosion every time it rained.

First batch of plants for around our front yard culvert:

In addition to the perimeter of the house and garage, it was also important to get mulch, stone, and plants set up around our culvert out by the street. This culvert was under typical pressure from direct rainfall, but also my neighbor’s sump pump and gutters, as well as water from our own sump pump.

Along with purchased stone, we also scavenged chunks of concrete from the job site:

To decorate the termination point in the culvert for our sump pump discharge, we decided to go with a combination of decorative stone and a variety of plantings. The usual suspects — Luke, Eduardo, and Jesus (not pictured) — were back to help us set up the culvert along with the border around our house.

The soil directly around the house had been visibly damaged by equipment and foot traffic during construction, so we decided to heavily mulch these areas without putting down cardboard first for sheet mulching, as we would later do for the remainder of the yard.

Our excavator was back for final grading:

With the final grading complete, we were ready to put down an initial layer of hardwood mulch. Here, again, the dingo proved its worth, as my wife used it to carry loads of mulch to the backyard.

South-west corner of the house as we put down an initial mulch layer:

Even with a shortened growing season, our new plants around the culvert were heading into their first winter happy and healthy.

Another view of the front yard after final grading and an initial layer of mulch has been put down.

Black and yellow garden spider:

Even with all the disruptions of construction, wildlife — of various sorts — was making itself known on site.

The mulch was down for only a few weeks, but it was long enough for some mushrooms to show up in various spots around the house. We were looking forward to seeing mushrooms sprout as the mulch breaks down. So far, we’ve been happily surprised at how quickly and consistently they began to appear.

As I dug out some clay soil in preparation for decorative gravel along our front walkway, this reddish spider showed up on our front steps.

Woodlouse Hunter Spider:

We were excited about building attractive habitat for local wildlife, so these early signs of life were encouraging, particularly since so little had been put in place up to this point.

Drywall and interior finishes were next up for the house. This work would occupy us through the winter.

In spring, we could look forward to sheet mulching and getting some basic structural elements of our Permaculture design in place.

In the meantime, we put the yard to bed for the winter as best we could, and, with the help of countless plant catalogs, began making our plans for next year.

First Spring: Sheet Mulching and Hügelkultur Bed

Sheet mulching a quarter acre suburban yard requires large quantities of cardboard. Luckily, a source near us, ABT Electronics, is happy to give it away in the form of appliance and mattress boxes. These thick, oversized boxes make relatively quick work of large spaces, which speeds things up when you’re trying to cover a lot of area fast.

After calling ahead to schedule a time to pick up the boxes, my daughter and I showed up in a rental van to load them up.

Once unloaded at home, we worked our way through the boxes, removing as much plastic shipping tape and staples as possible.

The boys and I began laying down the cardboard boxes just a few at a time, careful to overlap all of the edges by a few inches (this makes it tougher for weeds to fight their way through to the surface). After soaking the boxes with a garden hose, we then began putting down a thick layer of mulch over the top of the boxes.

At our previous home, I was used to putting down 2-4″ layers of mulch. Here, we were putting down 8-10″ of mulch, which seemed like a lot at the time. If I had it to do over, however, I would’ve gone even thicker, with a solid foot as a goal. Because there’s some settling that occurs once the mulch has been in place for awhile, and because it’s difficult to get a perfectly uniform layer across an entire lawn, I wish now we had gone thicker.

Looking back, another option, at least in the backyard, would’ve been to cut what remained of the existing turf at the back of our lot as low as possible, and then seeded the area with green manure, in the hopes that these plants could outcompete the existing ‘weeds’. If successful, then it would be possible to eventually cut down or remove the green manure plants in order to transition to fruits and veggies, or more ornamental options. If it worked, it would doubtless be less expensive than sheet mulching (time and money). Perhaps worth trying in a small area before expanding over wide expanses.

In terms of keeping costs down, one option is to call around to tree service companies in your area to see if they’d be willing to deliver wood chip mulch from felled trees and brush. Because this material is often destined for a landfill, which require disposal fees, companies will sometimes prefer delivering to your home for free.

In our case, we had mixed results pursuing this. When the timing was right, we managed to get a handful of deliveries from a couple of local companies, but it wasn’t always easy to match demand with supply (companies are unlikely to drive very far out of their way to deliver to your home).

With a good portion of the backyard complete, we moved on to creating our hügelkultur bed. The basic structure was formed using portions of our remaining elm tree, branches, twigs, and random pieces of bark. On top of this we placed a layer of topsoil mixed with some mushroom compost.

As with the mulch, we wish we had gone bigger with the hügelkultur bed. Even so, we used up every scrap piece of wood that we had on site, so if we had gone bigger it would’ve required that we bring in additional material.

If you look around online, you can see some impressively massive hügelkultur beds. Some so large they act as effective windbreaks.

A wider view of the backyard:

Note the diminutive shrubs off to the left. The purple sandcherry and dwarf blue arctic willow won’t stay tiny for long. While buying smaller plant options requires some patience, it makes meeting budget constraints easier, even as it allows you to purchase a wider variety of plants.

For the most part, I’ve been able to avoid designing-to-death every square inch of space in our yard. By adopting a more generalized idea of what I think can work in a certain area, it’s allowed for much more happy and successful outcomes, even the occasional happy accident.

This also helps when getting ideas down on paper, or even after plants have been purchased and you’re ready to put them in the ground. By being more open to various arrangements and combinations, the outcome tends to be more interesting, both aesthetically and even in terms of function.

Below is one area of exception. Pretty much everything shown was purchased and planted. In the case of these various shrubs, the idea was to create a living fence, one that offered privacy to my neighbor to the south, but also an opportunity for wildlife to have access to flowers, shelter, nesting sites, and even some fruit. By varying the heights and shapes of the plantings, we’ve tried to create more visual interest while avoiding the soldiers-standing-at-attention look that sometimes happens when the same plant is used down a long line to mark a border, as a windbreak, or for privacy.

Included in the list are dogwood, almond (they didn’t survive — we were pushing it in terms of climate region), purple sandcherry, a maple shrub, shasta viburnum, several privets, a weeping cherry, and a crabapple.

With the back and sides of the house mulched, we were able to move on to the front yard. With the house almost ready for us to move in, it was exciting to get plantings arranged by the front step.

As with much of the yard, we started with basic structural elements. For instance, a rain garden next to the downspout, with ample amounts of rock and what will become robust ornamental grasses. Also added into the mix are colorful favorites like echinacea, shasta daisies, penstemon ‘dark towers‘, and a few lavenders. Keeping the lavender next to the concrete steps, where we’re sure to brush up against it, will make easy work of collecting the spent flowers.

With a few adjustments over time, this setup easily manages the sometimes heavy flow of water from the nearby downspout. The first year saw some erosion in the mulch layer, but after adding some more stone as the plants had a chance to get established, this area has subsequently been issue-free and, arguably, one of the most cohesive and well-developed areas in the yard.

“Most of our job in relation to water is to intercept and direct its flow into a variety of storages — tanks, ponds, swales, rain gardens, livestock, plants, the soil — and only release it once it has done a whole series of duties… If you store water, you must also provide for its release and continued flow. You can only slow water down. You have a right to use it, but you don’t own it. All of it must sooner or later be released, if not to the stream, then to the soil or the air.”

— Peter Bane, The Permaculture Handbook

Boulders, gravel, thick mulch, and a variety of plants work together, encouraging water from the downspout to infiltrate rather than run-off. Over time, we’ve implemented this strategy at each downspout, even on the north side where there’s only a few feet to the neighbor’s property line. Even in this case, the goal is to encourage as much of the water exiting the downspouts to infiltrate into our yard, rather than escaping to the neighbor’s property. While the rocks and stones help to slow the water down, the thick mulch and plant roots are able to absorb surprisingly large quantities of water.

In theory, this strategy can even help recharge aquifers. If the infiltration is slow and consistent, it can encourage water to remain on site where it can be a source of water that some plants can call on during severe drought conditions. Instead of looking at water as strictly something to be gotten rid of (this is the case when it comes to the structure of our house), in permaculture terms it needs to be cultivated and managed in a way that’s beneficial to the plants and soil.

Out front, by the street, we added a parkway tree, some additional stone, and a handful of new plants.

Below, the view of the north side of the house and yard shows very little planted, and not much around the downspouts at this point. Because the north side is the smallest area in the yard in terms of square footage, and it gets minimal foot traffic, we decided to hold off on addressing it. It also gives us more opportunity to figure out exactly what we’d like to see on this side of the house.

The stone-filled culvert where water from our sump pump exits is both functional and slightly improved with the addition of mulch and a plant combination of Lychnis ‘Petite Jenny’ and blue iris where the water eventually passes out of the culvert and into our neighbor’s yard.

In the backyard, around the hügel bed, my daughter helped me plant a series of bare root fruit trees. Utilizing Ann Ralph’s techniques, laid out in her small tome, Grow a Little Fruit Tree, we cut these back hard right after planting. The goal is to keep these fruit trees compact but fruitful (ideally under 6′ tall to make harvesting easy).

“Ask yourself what seems best, listen to your own good opinion, and cut something out. These choices are entirely up to you and not nearly as consequential as you fear.

The tree responds. You watch what happens. You learn. The tree grows and creates new choices for you in the form of new branches. You can always make adjustments and corrections next time.”

— Ann Ralph, Grow a Little Fruit Tree

On the hügel itself, we planted a series of herbs, including sage, basil, and lemon balm, along with a series of strawberries. Later we would add some tomatoes and peppers. We also planted some potatoes that we’ve yet to dig up (the vegetation and flowers continue to come up each summer).

The trees in the backyard were a mix of nectarine, peach, plum, and cherry.

“In the climates where fruit trees grow, the orchards give the land an almost magical identity: think of the orange groves of Southern California, the cherry trees of Japan, the olive trees of Greece. But the growth of cities seems always to destroy these trees and the quality they possess.”

— Christopher Alexander, et al., A Pattern Language

In the front yard, we did a mix of red apple and Granny Smith (hopefully for apple pie one day).

In addition to fruit trees, we also planted a series of blueberries and strawberries, spreading them throughout the front and backyard, in the hopes of upping the quantity and variety of food available in each successive growing season. In the case of strawberries, we’ve opted for everbearing varieties.

Marking Progress

In the photo below, even though things look pretty thin so far, there’s actually a foundation of plantings that have been put in place.

For instance, in the back, off to the left, are the logs donated by a neighbor after their tree fell during a storm. Also, in the far right back corner, there’s a mix of Miscanthus giganteus and Sante Fe Maximillian sunflower, along with three ‘Tiger Eyes‘ Sumac and some ‘Walker’s Low‘ catmint. The Miscanthus and Maximillian sunflower (which is perennial) are our attempt at a bamboo alternative.

When fully grown, these plants range in height from 8-15′, offering the size and dense layering associated with bamboo (it takes 2-3 years for these two varieties to really get established).

The Sumac and catnip are complements in terms of height, flower color, and texture. The small yew evergreen will eventually be our perennial ‘Christmas tree’ once it matures (and gets wrapped in solar powered lights during the holiday season).

Immediately around the hügel are the fruit trees, matched with Russian comfrey (a favorite in Permaculture design) for added mulch and nutrients. We’ve had good luck with the comfrey — it’s easy to ‘chop and drop’ under each fruit tree several times each growing season. When it’s happy, comfrey produces large, vivid green leaves with dainty lavender flowers that bees love to visit.

Between the hügel and the back corner, there’s a mix of wildflowers and ornamental grasses. We’ll need to add to this area over time, as there’s still plenty of open space available.

There’s also been some erosion in the mulch layer after heavy rains. As the summer progressed it was clear that some areas, especially in the backyard, were showing signs of having thinned out. It was significant enough that we even had some weed seeds show up in a couple of areas.

Overall, the sheet mulching was incredibly effective at weed suppression. To date, the only ‘weeds’ that have managed to survive are Virginia creeper and some bindweed. The Virginia creeper is concentrated towards the back corner of the yard, intermingled amongst the Miscanthus and sunflowers. The bindweed pops up along the entire northern edge of our property.

Both weeds are sparse, emerging in only limited areas. They are easy to pull once they get a few inches up above the mulch. Unfortunately, this is the best option for controlling them, as any herbicide is unlikely to kill the entire plant. Clearly happy to grow and spread beneath the mulched surface, even if you managed to kill it in one spot, they’d likely pop up elsewhere.

Utilizing this disciplined approach of constantly pulling it as soon as it pops up was effective against a patch of chufa, or nutsedge, at our last house:

It took time, 2-3 summers in fact, but eventually the constant pulling seemed to exhaust the individual plants and they eventually disappeared. We’re hoping for the same result with these weeds. Worst case may be controlling rather than eradicating them altogether.

Interestingly enough, the lawn grass of our neighbors to our north and south is easily the most relentless invader, spreading by rhizomes, relentlessly trying to invade our mulched border. Several times a year we cut a groove into the line between our mulch and their grass, pulling up the grass that’s trying to get established in our mulch. It’s relatively easy work, but absolutely necessary in order to avoid being overrun.

As we put in new plantings we were always careful to pull back the mulch until we had dug down to the clay layer so that we could add actual soil before setting the new plants in place.

In many spots the cardboard hadn’t disintegrated yet, although there were a couple of areas where it was mostly gone. Presumably, in another year or two, it will be gone.

Digging down 8-10″ past the mulch layer to expose the original clay soil:

While putting in the new plants, we also saw evidence of white mycelium developing just below the surface of the mulch, along with plenty of earthworm, spider, and insect activity. All hopeful signs for the future health of our yard.

Apart from the decorative stone throughout the yard, the shrubs, ornamental grasses, and sunflowers are the basis of our structural layer (in visual terms) up to this point.

Later in the summer a couple varieties of basil pretty much took over the top of the hügel. To the left, a tuft of new leafy growth is visible on the fruit tree. In the background, near the house and downspout, the first year of growth on the Helenium ‘Dancing Flames‘ and the beginnings of a rain garden are visible, even though at this stage it’s still mostly just stone slowing down the water in this area.

A view of this same area, but from inside the house:

Erosion in the mulch layer is clearly evident in the many tiny gullies formed as water moved away from the downspout. Nevertheless, the stone and plants are in place to at least establish the beginnings of a rain garden.

During construction, when the ground was pretty much bare, our sump pump ran almost continuously during every rainstorm. With a heavy layer of mulch and the rudimentary beginnings of a rain garden at the mouth of every downspout, the sump pump ran noticeably less often, even during the heaviest of storms (in one case, 3″ in about an hour).

View from the south-west corner of the house: shrubs and grasses, just off the kitchen door, slowly getting established; the hügel and plantings in the backyard taking shape.

From left to right: four privets, Karl Foerster feather reed grass, Shasta viburnum, more grass, and then a crabapple barely in view.

In just a couple of years the privets and the viburnum will completely dwarf the grasses.

Another view of the backyard, this time from the far, south-west corner. In the foreground is a mix of perennials (flowers and grasses), beyond them is the hügel, and then, running along the southern edge of our property, the series of shrubs that one day should grow together into a living fence.

In the front, many of the perennials, especially the grasses, have enjoyed decent growth, and even the shrubs have leafed out well and taken on some new height. The area just behind the pile of stones was used extensively during construction as a staging area for building components, thus suffering a lot of abuse.

The soil in this area has compacted, and it’s been a struggle to grow much of anything so far.

To help this area recover we’ll try mostly a green manure mix, and then transition eventually to mostly flowers in order to add more color to the front yard.

Post-construction, this area has continued to be a staging area for materials, including gravel, decorative stone, topsoil and mushroom compost, and, of course, many yards of mulch.

If we can loosen the compaction in this area sufficiently, we could probably even sneak in at least three more fruit tree guilds.

First Harvest

In our first full season of growing we’ve had some nice development, although much of what we’ve planted is nowhere near maturity, remaining undersized and often wispy in appearance. This is to be expected so early in the process. The main goal, so far, has been to establish a base; both in terms of visual weight and in the long-term sense of function.

Even in the photo above, the rough outlines are present. For example, out at the culvert a series of plants are in place to absorb heavy rain events while also being resilient enough to survive periods of extended drought. The goal is to avoid having to water anything that far away from the house. Apart from last year, when the first plants went in, we’ve been able to let things flourish on their own. The thick layer of mulch does wonders in this regard.

They’re hard to see at this stage, but there are also apple trees, strawberries, and some blueberries planted in amongst the shrubs and perennials. They’re all just getting started.

Even though it’s early days for the yard, we’ve still managed to garner a decent harvest this first summer. From the backyard we’ve enjoyed a fair number of tomatoes, peppers, and basil. From the front, it was exclusively lavender and some peppermint.

Lavender we’ll use in satchels to go next to pillows or inside drawers for aromatherapy:

During our first full growing season we also managed to bring in our first flower cuttings, including two plants that have been a mainstay for us since our last house: agastache ‘Ava’, one of the more durable and long blooming flowers in our yard (loved by pollinators and hummingbirds alike); and Russian sage, an equally impressive magnet for pollinators. Also, one of our favorite perennial ornamental grasses, Palm Sedge, which helps to fill out and add texture to a bouquet.

In the fall, the hügel bed finally filled up a little. The fruit trees, which had been aggressively cut back in the spring, had taken on a nice flush of leafy growth. In the far back corner of the yard, our Miscanthus giganteus and Maximilian sunflowers were doing well, even if they were stunted in their first year as they acclimate to their surroundings. We look forward to next year when they grow together in a thick wall of leafy green, mimicking a stand of bamboo.

At this stage the yard is, admittedly, still looking mostly like a mulched moonscape. A small price to pay in order to patiently and methodically decide how we want to fill in all the remaining gaps. It was tempting to purchase enough mature, or at least semi-mature plants (at much greater cost, of course), to fill the entire yard and then hope we had guessed right in our placement and mix of sizes, colors, and textures.

Our approach, although it requires more patience, should allow us to experiment and observe seasonal changes as plants develop and grow together. And we’re certainly not afraid to remove or move things around to improve the relationships between plants.

In addition, the wildlife is still showing up, be it ever so slowly. Even with relatively few flowers, we’ve still managed to have our share of bees and wasps, hummingbird moths, and even a single hummingbird.

The dragonflies have taken notice of the yard, too, even showing up on a window screen to dramatic effect:

We had our share of mushrooms again this year, although not as much as we anticipated.

We even had a moth show up on our soffits, presumably to enjoy the breeze coming from air entering the vented attic.

More Mulch

Although we didn’t get to enjoy the yard as much as we would’ve liked (there was plenty of work to finish up on the interior of the house — trim, cabinetry, painting, and storage), we still had a lot of fun watching the yard come to life this year.

Even so, it was apparent by the end of the summer that most of the yard could benefit from a deeper layer of mulch. Our options seemed to be either wait a couple of years and add more mulch, or just do it now and hopefully be done with mulch for the foreseeable future. In the end, it seemed like it was easier to commit to mulching now rather than later, mainly because so much of what we had planted was still undersized, with plenty of gaps remaining between plants. If we waited even a couple of years, the plants would begin to fill out and knit themselves together.

When a tree service was working near my daughter’s school, and they agreed to drop off a few loads of wood chips, it seemed too good to pass up.

The wood chip mulch encompassed a wide variety of textures, particle sizes, and even the occasional clump of grass and dirt. Once it was down, it didn’t really look all that different from hardwood mulch. Initially it was more pokey, and just generally messy, but with some rain and time it flattened out and began to weave together into a carpet, similar to a quality hardwood mulch. By the following spring, after the sun had a chance to bleach the color to a mixed brown-gray, it was indistinguishable from the substantially more expensive hardwood mulches.

For the hügel bed I tried to build the mulch up in layers, giving it a terraced look. Over time this would mostly disappear, but it did seem to help with erosion on the mound.

With the first couple of loads I made sure to increase the depth of the mulch in the far back corner of the yard, around the Miscanthus and the sunflowers. After that area was covered, I worked my way up the north side of the yard towards the house.

Around the boulders in the photo above: at right, there is a mix of native grasses (in this case, palm sedge), and then between the two rows of boulders there is a combination of stachys hummelo and creeping thyme that is just beginning to take root. We hope the thyme will eventually spread out and spill over and around the boulders.

It was nice to at least get started on all the mulch that would need to be put down next spring. The cooler fall temperatures made it an enjoyable task.

Overall, things were progressing nicely and, even in this early stage, a yield was being produced (even if it wasn’t always for us).

Robins have discovered the crabapples outside our kitchen window:

Winter can test even the most celebrated gardens with deep, lingering snow, extreme fluctuations in temperatures, and harsh windstorms. Moreover, the structure of various plants is on full display, unable to hide behind lush foliage or showy flowers. Even though we have managed to fill some of the voids in our yard, the visual interest isn’t quite where we’d like it to be yet. But, then, that’s what ‘next year’ is for.

The front yard has only the beginnings of some structure, although, in this case, our ‘little black box’ in snow helps to improve the view.

One last look back at summer…

Our Energy Bills

4

The Logic Behind the Effort and Added Cost of Passive House

Passive House, as a building strategy, requires meticulous air sealing, along with ample amounts of insulation, carefully placed to eliminate or reduce the impact of thermal bridges through the building envelope. Once the air barrier of the building has been established, it requires mechanical ventilation to meet IAQ needs, along with high performance windows and doors to avoid undermining all of the air sealing and insulation.

Air sealing, water proofing, and thermal elements come together around one of our high performance windows.

All of these elements together, if successfully managed and implemented, should achieve a building that requires significantly less energy to operate and maintain at comfortable temperatures than any conventionally built structure of similar size and shape.

The Visitor enjoying some early morning solar heat gain through our kitchen window.

With a ‘conservation first’ approach (i.e., extensive air sealing and insulation), the goal is to reduce total heating and cooling demand as much as reasonably possible (while maximizing occupant comfort), with the possibility of adding renewables like solar or wind as mostly an afterthought to further reduce, or eliminate entirely, the remaining energy demand of the structure. It also typically means going all electric, so in our case it meant no natural gas (the normal fuel source in our area for a furnace and a hot water tank).

So far, our 11 panel 2.9 kW system has been averaging between 3,500-4,000 kWh of solar production per year.

A Passive House structure, by design, should use significantly less energy than any conventionally built counterpart of similar size and shape. This includes lighting (normally assumes only LED fixtures will be used) and other plug-in loads (e.g., Energy Star appliances), as well as hot water (typically a heat pump hot water tank, or a newer product like Sanden or Chiltrix).

Unfortunately, these loads are relatively ‘baked-in’, even for an existing, conventionally built home. For instance, a hundred year old home could switch all of their light fixtures to LED bulbs, replace old appliances with new Energy Star rated models, and change out a gas-fired or a conventional electric hot water tank to a high-efficiency heat pump model. In effect, they’d have pretty much the same reduction in energy use as a brand new certified Passive House of similar size and layout for these particular sources of energy demand. As a result, the real opportunities for driving down energy use in a Passive House are in the heating and cooling loads (mainly due, of course, to the extensive air sealing and insulation levels).

On most days the 15,000 Btu head in our kitchen and family room handles all of the heating and AC needs for our entire house. We have two additional heads in our bedrooms (9k and 6k Btu respectively), but they’re rarely used apart from the coldest and hottest days of the year.

Although there has been some moving of the goal posts as the Passive House programs have evolved over time, they remain challenging targets to meet.

Here are the current PHI requirements according to Passipedia: Passive House Checklist

In the case of PHIUS, the requirements have gone through several iterations, for instance, PHIUS+ 2015, PHIUS+ 2018, and most recently a fairly dramatic change to a prescriptive track to seek certification with far less onerous levels of paperwork and data collection required.

Overall, regardless of which model is pursued, PHI or PHIUS, the intent is to dramatically reduce the overall energy use of buildings by emphasizing the importance of air sealing, insulating to levels that exceed current code requirements (in most cases), along with quantifying things like thermal bridges, heating and cooling demand, and peak heating and cooling demand. The issue of energy demand or energy use is further complicated by the distinction made between Primary/Source and Site Energy.

Additionally, there’s been a growing consensus regarding the need to incorporate renewables in these building strategies, both in terms of financial feasibility and in terms of further reducing (or even canceling out altogether) net energy demand. And while it’s true that Net Zero is fairly straightforward to achieve (assuming needlessly large PV arrays are not utilized as a short-cut), it does require a commitment to meticulous air sealing and quantities of insulation that, along with the in-depth energy modeling, unavoidably add cost to any construction budget.

Zehnder ERV, Rheem HPHW tank, radon pipe with fan, and battery back-up sump pump. Elements that support proper moisture management, IAQ, and HVAC needs.

The opportunity for significant energy reduction also correlates with the size of the project. Because of form factor ratios, the larger the project (assuming a compact form is mostly maintained) the more energy a structure stands to conserve. This is why larger institutional, multi-family projects, or corporate-sized projects stand to be the biggest winners when it comes to the purported benefits associated with Passive House energy conservation.

Outdoor heat pump compressor after the snow, but before the worst of the 2019 Polar Vortex.

If executed properly, low energy demand will mean considerable financial savings. These savings are cumulative, year after year, rather than just a one-off initial price break, with the added potential to increase should energy costs go up.

In addition, there is the potential for less upfront expenditures for HVAC equipment (less heating and AC demand — at least in theory — means smaller and more cost-effective equipment required). In our case, in climate zone 5, where we get cold, dry winters and hot, humid summers, this didn’t prove to be the case. Combining the cost of our heat pump and ERV reflected roughly what we would’ve paid had we built a conventional home with a high efficiency gas furnace with a humidifier attached (fairly typical system in our area). Either way, it would constitute roughly a $20,000 expenditure for a house under 2,000 square feet. The level of indoor comfort, however, should be vastly different between a conventional and a Passive House build.

Even though occupant behavior can derail some of these projected performance outcomes, assuming that homeowners or tenants are reasonably educated on the best way to enjoy and benefit from the Passive House details, especially the HVAC systems (normally this means commissioning units and then mostly leaving them alone in terms of settings), this should not be a stumbling block for most builds.

While all of this becomes more challenging with a smaller, more compact build like our 1,500 square foot single-family home, the possibility of significantly lowering energy demand is no less real, along with the cost savings. Not to mention the level of occupant comfort, which I personally feel is the main selling point of the Passive House building principles.

Some Background Information on Our Home

A quick summary of our build would include our blower door score of 0.2 ACH@50 (106 cfm@50), along with the following R-values for the structure:

R-16 Below the basement slab

R-20 Exterior of the basement foundation

R-40 Exterior walls

R-80 Attic

In 2019, our first full year of occupancy, with three of us (my wife, daughter, and myself) we had a total of just over 11,000 kWh of energy use. This included lighting, all other plug-in electricity demands (appliances, TV, computers, charging cell phones etc.), along with our HPHW tank and all of our heating and AC needs. It also included countless hours of power tool usage as I finished up interior trim, doors, along with some shelving and storage projects after we moved in. Record low temps during a Polar Vortex event in late January and into early February added to the total as well.

For 2020, a substantial increase in overall energy use might have been the expectation after the outbreak of COVID-19. Yet even after subsequent stay-at-home guidelines that began for us in March, we actually ended up at 10,446 kWh, a slightly lower annual number compared to the previous year. This lower total happened even with all three of us being home most of the time, with no breaks even for vacation time, outdoor activities that require some travel, or normal visits to family out of town.

If there’s a payoff in pursuing Passive House, it has to be in the combination of lower energy costs and increased occupant comfort when compared to a similar, conventionally built home or structure.

This lower number was in keeping with our usage during our first nine months (April-December, 2018). If the Polar Vortex was an anomaly (everyone hopes that it was), then most years going forward should be around 9,500-10,500 kWh for total annual demand. In part we think going over 11,000 kWH our first full year reflects just how significant a colder than normal winter can be on overall energy use in a Passive House, not to mention heating demand more generally (whether it’s a Passive House or not).

Moreover, for a family of three and a structure of this size with similar performance specs, it seems to suggest that our 3-4,000 kWh of annual usage per person is mostly ‘baked-in’. Meaning, in terms of occupant behavior, there’s not much we could do to further lower these numbers. Perhaps we could take fewer showers, cook less at home (stove and dishwasher), do less laundry, only ‘live’ from dawn to dusk (to avoid using artificial lighting at night), not do any woodworking or other DIY projects (use power tools off site?), and heat the home to only 60º F in the winter and cool to only 85º F in the summer. Obviously, these would be rather extreme measures to chase after the last final few kWh of energy use and, arguably, it wouldn’t be particularly meaningful apart from bragging rights should we end up with a lower annual total.

After all, it’s fair to ask what’s the point of the air sealing, insulation, and triple pane Passive House windows and doors, if it doesn’t produce a much more comfortable day-to-day living experience for those living inside the home or building? If simply chasing energy use were the main objective, reducing it no matter the consequences, then removing all the windows and doors and replacing them with continuous R-40 walls would be a good place to start, but hardly worth considering for obvious reasons. If there’s a payoff in pursuing Passive House, it has to be in the combination of lower energy costs and increased occupant comfort when compared to a similar, conventionally built home or structure.

In terms of unexpected surprises, really the only unanticipated energy use was the need for dehumidification on the hottest and most humid summer days of the year.

After our first summer in 2018, when part of the excess humidity was likely due to new construction moisture present inside the structure, we’ve been averaging about 30-40 days a summer, including a few random days in spring and fall, when the dehumidifiers are running intermittently. We set the units to 50% relative humidity, but normally they shut off around 55% based on gauges placed around the house. We try to keep the house under 60% RH. The risk for mold increases above 60%, but it’s mainly at that point when humidity levels make us feel noticeably uncomfortable.

Also, we didn’t think about the energy use associated with power tools for woodworking and arts and crafts projects. Without tracking it, we can only guess that it represents a few hundred kWh a year, rather than something in the thousands. We’ve been doing plenty of projects around the house our first three years, but still far less than what a full-time woodworking company would require. Even so, along with the potential for a EV charger, it’s something to think about when designing a new home or retrofitting an older one, especially if renewables are part of the equation and you’re trying to establish likely annual demand.

Actual Energy Use: Demand and Costs

The breakdown is as follows:

Based on our first 2.5 years in the house, we can expect 10-11,000 kWh of total energy use per year. Again, for some context, this is for a family of three, in a 1,500 square foot single story home that has a full basement.

In our first full year, 2019, we exceeded 11,000 kWh mainly due to the Polar Vortex. Compared to our first winter, along with numbers for this current season, it looks like the Polar Vortex added nearly 1,000 kWh of demand above a more typical January – March time period.

Over the course of our first 2.5 years (our first year was April-December), the numbers have been surprisingly consistent across seasons and month-to-month, regardless of our level of activity in the home (e.g. guests staying over, vacations away from the home, power tool use, etc.).

For instance, even in our first June, back in 2018, when the house was still drying out from new construction related moisture, and we felt compelled to start using two dehumidifiers to control excessive humidity (one in the kitchen and one in the basement), total energy use for the month was 616 kWh.

The following June, in 2019, we ended up with an even higher number, at 786 kWh of demand.

For June of this year, even with stay-at-home restrictions for COVID-19 in place, so a reasonable expectation might be for still yet higher demand, we actually ended up at a lower 605 kWh of use.

On a side note, it’s probably reasonable to assume COVID-19 had some impact on overall energy use for 2020, but after going through the numbers, it just seems unlikely that it contributed more than 500-1,000 kWh to our annual usage. We should have a better idea of its full impact once winter is over.

Presumably, without a granular study of day-to-day conditions, including day and night temperatures, along with relative humidity data, not to mention minor fluctuations in how we used the AC or how much laundry we were doing over these same three periods, it’s hard to explain this deviation with any level of certainty. Suffice it to say, we can expect June usage to normally be in the 600-800 kWh range. Obviously, a June in the future that experiences a heat wave like the one Chicago experienced in 1995 would likely drive the final number well over 800 kWh, but hopefully that remains a singular event rather than a more normal June.

In other words, even in a year where the weather remains milder than normal for a full 12 months, and we’re all exceedingly busy and rarely at home, our total energy use for the year, at best, will likely still end up in the 9,000-10,000 kWh range. And even if there was just one person living here, it’s hard to imagine they could keep total energy usage much below 4-5,000 kWh on an annual basis since so much of the demand is ‘baked-in’, as previously noted above.

Here is the monthly breakdown of energy use for the first full year we were in the home for 2019:

January: 1,738 kWh (includes 2019 Polar Vortex; following January was only 1,374 kWh)

February: 1483 kWh (the following year was 1,237 kWh)

March: 837 kWh (following year was 561 kWh — clearly a bitterly cold winter)

April: 681 kWh

May: 473 kWh

June: 786 kWh

July: 612 kWh

August: 608 kWh

September: 630 kWh

October: 812 kWh

November: 1,166 kWh

December: 1,237 kWh

Total energy use for 2019 was 11,063 kWh.

In this same period, our solar panels produced 3,863 kWh, so net demand for the year was 7,200 kWh (this requires some math using the billing statements from our utility company and the Enphase Enlighten solar app).

Our monthly bills for electricity in 2019 totaled: $1,075.89.

Because of our SRECs, which for us totaled $848 for the year (paid via quarterly checks), our net energy costs for 2019 were $227.89 (an average of $18.99 per month).

For comparison, numbers for 2020 were: 10,446 kWh of demand, while solar production for the same time period was 3,675 kWh, for a net energy demand of 6,771 kWh.

After SREC payments (again, totaling $848 for the year), our net total cost for 2020 was $189.36 (an average of $15.78 per month).

The SREC payments (these are based on a 5 year contract) reduced our annual cost by $848 each year, with a net average cost for our first two years of just $208.63 per year for all of our energy needs (a roughly $17.39 per month average).

Without any solar panels or SRECs, our electric bill would be roughly just under $1,500 per year based on current rates. By way of comparison, a new code-built home of the same size would likely pay more than twice this amount — an older home still more, assuming less air tightness and insulation, combined with a less efficient gas furnace for HVAC and domestic hot water.

It’s worth noting that as building codes tighten up their performance metrics, the difference in total energy demand between code-built and Passive House homes should continue to shrink. This assumes, however, that any number of ‘ifs’ are successfully overcome. For example, if air leakage is accurately measured (is there enforcement should the structure fail?). If a proper Manual J has been completed. If HVAC ducts are sized, installed, air sealed, and insulated properly. If insulation has been properly installed in appropriate quantities throughout the exterior walls and roof. If thermal bridges are avoided. If moisture (bulk and water vapor) is appropriately addressed and managed. This is a lot to get right, and it’s easy to get any number of things wrong, even with inspections and third party verification.

As pointed out earlier, since we’ve moved in we haven’t aggressively pursued trying to lower our energy demand. Instead, our approach has been to live ‘normally’, enjoying the benefits of the air sealing, insulation, and our HVAC set-up. We set and mostly forget our heat pump at 70º F in winter, 75º F in summer, in order to try and better understand ‘real world’ energy demand in a tight, well insulated and appropriately ventilated home of our size.

Hopefully some of this information can benefit others in the planning stages of their own Passive House, or Pretty Good House project. Moreover, in addition to WUFI analysis and PHPP, BEopt is another modeling option for figuring out energy demand and cost-effective design elements for a structure (new or old). The new calculator from PHIUS would also be a good place to start: PHIUS+ 2021

For anyone who wants an easy, initial test of their current home’s energy efficiency (EUI), a calculator like this one may be helpful: Energy Smart

Numbers for Heating and Cooling

In spring and fall when there’s less demand for heating or AC, our baseline monthly energy usage is below 500 kWh (this has been fairly consistent over the course of our 2.5 years in the home, even during COVID-19 when the three of us were home most of the time).

If this low demand could be maintained for much of the year, as it is in milder regions of the country like in parts of California, our annual usage could be cut by more than half (it wouldn’t require R-40 walls or R-80 attics to achieve either). Moreover, in these more temperate regions of the country with reduced insulation needs, and therefore less demand on HVAC systems, ‘green’ building programs like Passive House and Net Zero become even more attractive since they’re far more cost effective and easier to achieve.

In our case, summer months typically run about 600-800 kWh of actual usage, dependent on the number of days above 82º F when we typically find that we need to turn on the AC. Even on these days we will turn it off if there’s a sufficient drop in outdoor temps overnight, which allows us to open the windows (dependent on outdoor humidity or rain).

It might be worth noting that even though we thought we’d regularly open our windows whenever the weather was remotely nice, this hasn’t turned out to be the case. Between having to monitor indoor humidity levels, and the ability of our ERV to deliver continuous filtered fresh air (it’s shocking how quickly our fresh air supply filter turns black — within a month or two at the most), apart from the few days a year when the weather is perfect for opening windows, they mostly just stay shut. Much like Jim Gaffigan’s quip on seasons here in the Midwest, “Spring, that’s a fun day,” because the weather tends to be so mercurial there just aren’t that many days or nights when we feel comfortable leaving the windows open for extended periods of time.

On the plus side, it’s not uncommon for us to wait until there are 2-3 successive days where temperatures rise above 82º F before we feel the need to turn on the AC. In other words, there is some truth to the idea that Passive House buildings take some time to heat up or cool down based on outdoor conditions, although this can be quickly undermined by an ERV/HRV that’s set on high or in boost mode for long periods of the day (lots of cooking or showering, particularly relevant in the case of larger families, would make this a necessity) .

“Heating and cooling energy – that which is most reflective of the efforts of the design and construction process – is a small percentage of the total energy usage. As Andy Shapiro says, there is no such thing as a net zero house, only net zero families. Occupant choice matters hugely.”

—Marc Rosenbaum‘s report on South Mountain Company’s Eliakim Net Zero Energy Project

During the heart of winter, our total energy demand is in the range of 1,000-1,500 kWh per month. Even in January of 2019, with a Polar Vortex event, our bill still managed to stay below 2,000 kWh for the month. During this same week, however, we saw minimal benefit from our solar panels since they were covered by several inches of snow during the sunniest (and coldest) parts of the billing period.

These elevated kWh numbers during winter reflect just how much harder our Mitsubishi heat pump system has to work in order to maintain indoor comfort because of the Delta T between outdoor and indoor temperatures. And we can hear the difference: while in summer the system is virtually silent, in winter, especially as temps head towards zero, we can hear the compressor outdoors working to keep up. Compare this to summers: 75º F indoors vs. 95-100º F outside on the hottest days of the year, even though it’s significantly cooler for most of the summer, thus helping to explain the lower overall energy demand for AC usage in comparison to heating demand.

Cooling, unlike the demand for heating, is relatively comparable to what it would be in a conventional new build. In summer, the Passive House ‘thermos-like’ structure is mostly a hindrance rather than a benefit to keeping the interior comfortable. All the ‘free’ sources of heat in winter, e.g. south-facing windows on sunny days, body heat from the occupants, heat given off by computers, TVs, appliances, and even LED lights or our heat pump dryer, either thankfully don’t exist (in the case of south-facing glass because of sufficient overhangs) or they actively contribute (however small in some cases) to the overall cooling load.

In addition, because cooling loads are relatively low, and the efficiency of the mini-split heat pump is so high, even as the multiple indoor heads have no issue maintaining comfortable temperatures (we rarely notice the system — wall units or outdoor compressor — running in summer), it leaves us with a latent load that we need to address with two stand-alone dehumidifiers, indirectly adding to the overall cooling load.

So of our roughly 10-11,000 kWh per year of total demand, without an actual energy use monitor like TED on our main panel to establish exact numbers (a review of similar product options: here), it looks like just over 3,000 kWh is used for heating, with another 800-1,000 kWh used for cooling needs (at least in a typical year). In years where there’s a significant Polar Vortex event, or should a summer in the future experience an extended heat wave, then our numbers for heating and cooling are likely to hit 5-6,000 kWh of demand. With climate change, these numbers are invariably going to fluctuate or even grow depending on just how severe weather patterns become over the ensuing years and even decades.

Notes on Designing a Heat Pump System for Passive House

An issue worth considering, especially for those in the design stages of a build, is the added efficiency of a 1:1 set-up for heat pumps, meaning one outdoor compressor for each distribution head indoors (or air handler). There appears to be a growing consensus that this layout will offer added efficiency because of improved modulation over what has been a more typical set-up, like ours, which is a multi-zone system that has multiple distribution heads on a single compressor. It’s hard to imagine, at least in our case, that this impact could be more than a few hundred kWh per year, but worth exploring when having someone do a Manual J and S.

Additionally, we haven’t experienced any issues with the distribution heads in the two bedrooms (9k & 6k Btu’s respectively), either for heating or cooling, although concerns about the effectiveness of these undersized units in smaller bedrooms often comes up in discussions on how best to design and layout a heat pump system on Green Building Advisor.

When designing our system, I don’t remember this issue of 1:1 vs. multi-zone heat pump set-ups being discussed in any of the information I was able to hunt down, either in Passive House related books, or even online resources. I also didn’t come across discussion of the need for active, separate dehumidification while designing our build in 2016. These are just two examples demonstrating that Passive House is still actively evolving as a ‘green’ building program (potential overheating in winter and shoulder seasons would be a third example).

A cautionary tale for designers, as well as building owners, to guard against hubris as the construction drawings develop or when the details are finally executed on a construction job site. Other issues may arise with Passive House builds in the coming years, so it’s worth considering potential unintended consequences before finalizing details. Today’s solution may be someone’s costly headache tomorrow.

Additional Solar Panels to Achieve Net Zero?

Based on what we’ve been paying for energy in these first 2.5 years, we don’t feel compelled to add more solar panels at this time. Should the SREC’s dramatically fall in value with a new contract, or disappear altogether, it might encourage us, at that point, to purchase more panels for the roof. But even so, at less than $90 per month, even without the SREC’s, it makes our energy bills a relatively painless expenditure (roughly equivalent to one nice restaurant dinner for the three of us, or still less than what we pay on a monthly basis for things like coffee, breakfast cereals, and milk). Put another way, averaging around 3,500 kWh per person of demand, whether with or without the solar panels and our SRECs payments, our monthly energy bill is typically cheaper than a single visit to the grocery store.

Because of the effort and money expended upfront for air sealing and insulation, all while trying to carefully manage window placement and HVAC layout successfully, we’ve managed to whittle our energy costs down to something highly affordable and resistant to significant cost increases. This should remain true, regardless of what’s happening in the market in terms of prices for natural gas, coal, or nuclear power (i.e., the major sources of power in our region, here in the Midwest). Worst case scenario, we add additional solar panels to get to Net Zero or even Net Positive in order to cancel out what remains of our monthly energy bill. This would require an additional 7-8,000 kWh of annual solar production, or roughly three times what our current system produces.

In our specific case as a household — averaging between 3,500-4,000 kWh of solar production per year (this amounts to nearly 40% of our annual demand), combined with SRECs — we nearly end up at Net Zero, at least in terms of total cash spent for energy (arguably the most important — maybe the only — metric that homeowners ultimately care about; whether it’s the total cost to build a new home, or in terms of the annual energy bill). As a result, there’s not much financial incentive to purchase additional solar panels to achieve absolute zero energy consumption (this is in site energy terms only). The fact that this all comes with a house that’s extremely comfortable and quiet to live in, regardless of season or room, makes our home only that much more valuable to us.

Passive House + Net Zero?

In addition to designing for Passive House, there is the question of Net Zero or even Net Positive buildings. While Passive House strategies eliminate a significant portion of overall demand by requiring a significant outlay of upfront funds for air sealing and insulation, once this pill has been swallowed, it’s normally cost-effective to incorporate renewable energy of some kind to cancel out the expense of the remaining energy bill.

A quick side note: An excellent resource, one that I found only as our build was coming to an end, is William Maclay’s book The New Net Zero. It contains a wealth of information, but, in particular, many specific construction details vividly illustrated. This is especially valuable for DIY builders, or even seasoned professionals, when evaluating all the possible elements of roof-wall-foundation assemblies.

Also worth noting, if this approach (Passive House + Net Zero) were adopted on a national level, including renovations, it would eliminate a large portion of aggregate energy demand, thus having a meaningful impact on greenhouse gas emissions and global climate change (up to 40% for construction and existing buildings).

Based on what we know at the moment, a combination of approaches — including Passive House building principles, Zero Carbon goals, and the use of renewables — could be the way out of the climate crisis over the long haul. In addition, if adopted as part of building codes, it could mean properly training the next generation of tradespeople (like European-style apprenticeship models, thereby also improving the build quality) while also being a tremendously effective jobs program.

Beyond Net Zero, or even Net Positive, in regards to energy demand, there is increasing awareness about carbon emissions more generally, and the variety of ways to radically reduce or sequester it, including the choice of building materials (for new construction or retrofit projects) or even how we decide to landscape our yards.

Passive House Cost Premium

Unfortunately, due to relatively inexpensive utility rates here in the Midwest, even though Passive House (or Pretty Good House) offers a significant reduction in energy costs if done well, when considered as a percentage of household income the numbers may appear much less impactful or motivating when faced with line items in a build budget for things like air sealing and levels of insulation that far exceed building code requirements.

In our case, the annual energy savings compared to something code-built would likely be in the $2-3,000 range. Fairly significant, but if the purchase price of the home is $500,000 – 1,000,000+ (fairly typical here in the Chicago suburbs for new construction) then even a $100,000 savings over the course of a 30 year mortgage may not convince someone to move beyond conventional construction practices (particularly if they have their heart set on a long list of high-end finishes and appliances). The upfront costs associated with meticulous air sealing and added levels of insulation — if not viewed as an investment in build quality — will likely appear frivolous to the average consumer.

“One of the issues we face here is the fact that energy is cheap, like most things in the Midwest. We don’t have the financial burden placed on us that the coasts do—real estate-wise and energy-wise. So there is not much enthusiasm around green building on a financial level; it’s almost always an ethical issue. The people who are interested want to do a good thing for the environment, as opposed to saving money on their utility bills. Another thing is that people are accustomed to discomfort—we have drastic and frequent temperature swings. It’s really humid in the summer and freezing in the winters, when drafty windows are just accepted. They are used [to] it, so it is hard to sell them on high-performance windows to be more comfortable; or taking measures to keep a basement from being wet—they just aren’t concerned about it. There’s a complacency that we fight against; there’s not enough financial gain to incentivize making upgrades.”

— Travis Brungardt, GBA Q&A

Looking solely at upfront costs is likely to discourage most prospective homebuyers from pursuing Passive House (or even Pretty Good House in many cases), whereas looking at the cost of ownership, including the cost of monthly utilities, produces a more accurate comparison (note, however, this assumes the homeowner can stay put for at least the next twenty to thirty years).

A cost of ownership calculation should also acknowledge less maintenance costs year-to-year since, if the structure is detailed well, it should experience far fewer issues (none ideally), especially damage caused by bulk water intrusion, mold, or even air leakage. Granted, it may take a decade or more before this kind of damage is found in a conventional home, but when it is, it’s rarely (if ever) inexpensive to properly correct.

Hard Choices

As a culture, we have been in a similar place before. One quick example would be automotive engineering applied to car safety. In terms of perspective, if you get the balance between cost and safety wrong when evaluating value, then seat belts, air bags, and better designed bumpers might seem like misspent dollars.

“Nader argued that Detroit willfully neglected advances in auto safety, like roll bars and seat belts, to keep costs down… But using [seatbelts] was strictly voluntary. And many Americans didn’t want to.”

— Daniel Ackerman, Before Facemasks, Americans Went to War over Seat Belts

In a similar vein, the American consumer has been taught by the market, realtors, and builders to believe cost per square foot is the gold standard of value. As a consequence, little emphasis is placed on building science basics such as air tightness, proper moisture management, thermal performance, or indoor air quality. In layman’s terms, this means the average American home is leaky, parts of it have likely been damaged by bulk water or mold, and it’s uncomfortable in terms of indoor temperatures and humidity, all while delivering subpar air quality to its occupants.

In terms of quality construction and ‘green’ building (Passive House or not), the hard truth is there really is no free lunch (not even renting: rentcafe). Quality, of any kind — finishes, proper moisture management, occupant comfort, even reduced energy bills — has its price, but only those who recognize its value will be willing to pay for it.

Regardless, as homeowners we either pay upfront for the air sealing and insulation, along with high performance HVAC for better IAQ, or we pay monthly (and perpetually) in the form of higher energy bills (this normally comes with less occupant comfort) and far inferior IAQ. Either way, the money is going to be spent, it’s just a question of when (upfront vs. long term month-to-month) and for what (air sealing and insulation vs. mediocre systems and underwhelming outcomes that require costly maintenance over time).

As with car safety in the past, depending on one’s point of view, the answer to these kinds of construction and homeownership options are either obvious or nonsensical. Nevertheless, regardless of the path taken — conventional construction or some version of high performance — no one’s wallet will remain closed for long.

Flooring: 3/4″ Hardwood

4

Hardwood vs. Carpet

In our previous home we made the decision not to use any carpet. Not only did we prefer the look of combining tile (for wet areas) with hardwood (living areas and bedrooms), we also knew these surfaces would be easier to keep clean than carpeting. Although I grew up in two homes that both had mostly wall-to-wall carpeting, it was only after having to rip up several rooms of carpet that I realized just how much dirt and general detritus gets trapped below the surface.

There does seem to be an element of generational change (some would argue even social class) involved in this choice between carpet and hardwood. For example, my parents, who grew up on farms in the 1940’s without carpet, were shocked that we preferred hardwood flooring since having wall-to-wall carpeting was a big deal for them when they moved to Chicago in the late 1950’s. To them, hardwood flooring signified the outdated past while carpeting was the future.

Having lived with both, I don’t think I’d ever choose to go back to carpet. In addition to being much more visually interesting, I find hardwood flooring not just easier to keep clean but much easier to fix or repair should damage occur.

Which species of wood?

For our last house we went with pre-finished 3/4″ x 5 1/4″ wide plank Australian Cypress. Even though we loved the look of the Australian Cypress, it was more expensive than other species and it seemed to dent more easily than its Janka hardness score would suggest.

Oak is, by far, the most popular wood species for flooring, seen in countless stain color variations, but we wanted to try something with more natural color variation from one board to another.

For our new home we knew we still wanted to go with only hardwood and tile, even though there are now more eco-friendly and sustainable carpet options. We also knew we’d have to utilize a low or no VOC finish for the wood flooring in order to maintain a high level of indoor air quality.

Another option to consider is engineered vs. 3/4″ solid hardwood flooring. Because of the additional wear layer, and because I’d previously worked with a solid hardwood in my last house, we opted for the 3/4″ solid.

Also, since we went with a prefinished hardwood last time, this time we decided to try a traditional install, meaning sanded and finished in place.

The only real gripe we had with the pre-finished flooring in our last house was the beveled edge between boards, creating grooves that can trap dirt. Also, we felt it was slightly less visually appealing than a traditionally finished floor. Nevertheless, we would consider pre-finished flooring to be a viable option, especially if you’re having to work under severe time constraints and you need a room or whole house completed quickly.

3/4″ x 4″ Hickory

After considering various wood species, we settled on Hickory since it can look similar to the Australian Cypress, while its Janka hardness score is slightly higher, giving us some added durability. It’s also harvested and shipped from within the US, so it cuts down on shipping costs and total embodied carbon emissions.

Looking around locally, including our local Floor & Decor, I could only find manufacturers who packaged their flooring in boxes of shorter boards (the longest boards typically in the 4′-7′ range). Using shorter boards tends to produce a choppy look, reminiscent of a brick running bond pattern.

Online the options seemed much better, although shipping costs had to be factored in. It was also difficult to find the color variation we were after since much of the Hickory that’s available would be classified as clear or select (NWFA). In the end, we used Countryplank, ordering their Old Growth Hickory in random lengths (2′-10′).

After initially receiving someone else’s order in an entirely different species, Mark from Countryplank quickly took care of the problem and got my correct flooring to me the following week. Once it showed up on site, the boys were back to help me carry it in the house — as always, many thanks to them for helping us out with the grunt work.

unloading wood flooring
Smitty and Ricky helping us unload the truck.

Of course when the flooring was being delivered it turned out to be one of the coldest days of the year with plenty of snow around. Thankfully, with the guys helping us, it went pretty quick.

Installation

Before installing the Australian Cypress in my last house, I used a book from Don Bollinger as a helpful how-to guide. The book came with a video companion, which I’ve since lost, but much of the footage has shown up on YouTube:

And there are many other helpful videos available as well:

After clearing a room of tools and other construction related items, I set to work prepping the Advantech subfloor.

family rm b4 wood floor
Setting up to prep the family room subfloor.

Although the Advantech is said to resist moisture better than other OSB or plywood subflooring, because of the delay in construction after firing our pair of GC’s, the sheets of Advantech saw more exposure from the weather than is ideal.

Nevertheless, apart from having to grind and sand down some edges that had expanded due to moisture, the Advantech held up incredibly well. In addition, since the framers used nails to fasten it to the floor joists I went through each room adding decking screws to help stiffen the floor even more.

Once this was done, I was able to put down some red rosin paper. In my last house I had used 15# roofing felt, but since it’s embedded with asphalt I decided, for the sake of indoor air quality, that the red rosin paper was the better option. Rather than using it to control moisture, it’s mainly helpful in keeping a neater workspace as the flooring goes down.

mbr red rosin
Red rosin paper going down in the master bedroom.

With all of the red rosin paper down, it was time to bring in the tools and to start arranging piles of wood flooring based on length and color. As I unwrapped each pile of boards I went looking for the longest and darkest boards, making sure to have them nearby as I tried to use the longest boards first, and then be selective about how to place the darkest and most attractive pieces. When all the rooms were complete, I wanted the leftovers to be mostly shorter and lighter colored pieces.

family rm prepped 4 wood
Family room prepped for hardwood flooring.

The only other major decision before beginning to install the flooring was orientation. Most homes utilize the longest wall in a space as a guide, installing the wood parallel to this wall. Ideally this would also mean the flooring runs straight from the front door entry area to the back of the house in bowling alley fashion. This assumes the floor joists are perpendicular to the direction of the wood flooring. In our last home, and in our current Passive House, we could have oriented the hardwood flooring in this ‘straight’ pattern, but after trying and loving a diagonal pattern in our last home we knew we wanted to stick with this angled pattern. The only significant downside to the diagonal pattern is additional cuts are necessary so, therefore, more wood is required.

family rm wood going down
Arranging pieces before getting started.

The use of spline pieces, or split tongue, was helpful when making a change of direction, or establishing the border where the hardwood flooring met the tile in the kitchen, utility room, entry, and bathrooms.

kitchen outside corner w: router
Finishing up the family room. Note the shorter pieces of spline on the tile, and the router used to make a connection between the main pieces and the wood border next to the kitchen tile.

When I needed to create a groove I used a groove bit with the Bosch router before gluing and installing a section of spline. This was especially helpful where the wood met up with tile and I needed to first create a border piece.

First, using a table saw I would cut off the tongue side of the board, facing this side towards the tile. Now with the groove side exposed I could cut to length the piece I needed to butt up against this border piece against the tile. Once it was cut to length I could use the router to make a groove on the end that would be in contact with the border. With the border piece and the field piece now having grooves it was easy to add the spline in between, making for a tight, durable connection between these two pieces with some wood glue.

family rm mostly done
Done with the family room and ready to head towards the front door.

The diagonal pattern also means that the flooring nailer runs out of room before you get to the wall because of the angle involved. For these last few inches I utilized a trim nail gun, shooting into the tongue and face nailing a couple of nails at the outside edge. Even though these nails are significantly weaker than the flooring nails, we haven’t experienced any gapping or other issues at the perimeter of our walls. This may be due to the fact that we don’t see wide swings in the levels of indoor humidity (typically the house stays within 30-55% relative humidity; most of the year hovering around 40%) because of the air tightness and high levels of insulation required of a Passive House.

It probably also explains the lack of floor squeaks. When there are wide swings in outdoor humidity we sometimes get a couple of ‘pops’ from the wood flooring itself, but we’ve never had an issue with the floor joists/Advantech connection squeaking. In our last home, a conventionally built tract home, similar changes in humidity made our wood floors sound like they were in a hundred year old farmhouse, popping with almost every step until the humidity and the wood itself had a chance to stabilize.

One of the best tool purchases for the entire build was this Powernail ‘persuader’. Whether at walls, or out in the field, this tool works exceptionally well at closing unsightly gaps that would otherwise need to be filled with wood filler.

powernail persuader
The Powernail ensured a much tighter floor installation.

And the Powernail was an excellent guide for identifying bad boards — if it couldn’t close gaps on a particular board, it meant that board shouldn’t be used.

For spots or areas that would need some extra attention during sanding, I marked these with a pencil, either with an X or a circle.

marks for xtra sanding
Spots requiring careful sanding marked with X’s or circles.

Before sanding I also went around applying wood filler to all of the nail holes, any voids in the many knots, and to any remaining gaps between boards (mostly where the ends butt together). For the deepest voids in the knots I made two passes with the wood filler, sanding in between coats. In the end this produced a much smoother finish.

I found the Timbermate brand online, and was pleasantly surprised at how easy it was to work with and how well it’s performed over time. I started out with half a dozen different colors, but eventually narrowed this down to just two colors: Beech/Pine and Chestnut. In effect, these two colors spanned the wide variation in color from light to darker boards.

Although it claims to be zero VOC, it does have a distinct and slightly funky smell as it comes out of the jar. This odor completely disappeared once it was sanded down and the floors were sealed with tung oil. The Timbermate is also very easy to sand smooth.

wood putty for floors

Sanding the Floors

Thankfully, the flooring didn’t require a lot of sanding, nowhere near the amount typical in strip oak flooring. Overall, the flooring did seem to be precision milled and I ended up with very few completely unusable boards.

not much sanding
This was about as bad as it got. Most boards came together much better than this.

I could’ve rented a traditional floor sander and edger, but after reading about Festool’s orbital sander and then a similar sander from Bosch, I decided to try the Bosch out and see what it could do. I started in a smaller room, my daughter’s bedroom, just to see how long it would take to do a room-sized amount of sanding. Starting with 40 grit for the worst areas, I slowly worked my way through increasing grits, ending at 150 for a smooth finish ready for tung oil.

Since I was able to work through the various grits in just over an hour, I decided to keep using the Bosch sander for the duration of our project. Again, if I was sanding conventional oak strip flooring purchased from a big box store, I definitely would’ve rented the normal sander/edger combo.

bosch sander
Bosch orbital sander.

Since I was installing and finishing room by room (we had a lot of construction ‘stuff’ to maneuver around, but that we wanted to keep onsite), renting the equipment, in addition to being more expensive, would’ve meant a lot of back and forth between home and the tool rental center. Also, once the flooring was done, I still owned an excellent sander. It’s easily the best sander — palm or orbital — I’ve ever owned. The lack of vibration compared to comparable sanders makes working with the Bosch a real pleasure.

bosch sander ready to go
Utility room ready to be sanded.

Hooked up to a shop vac with a HEPA filter, the sanding dust was kept to a bare minimum, making the house pleasant to work in, regardless of the amount of sanding just completed.

Just before starting the wood floors my Fein shop vacuum died on me. I picked up a Ridgid brand vacuum from Home Depot mainly because it was the quickest option, fully expecting to be disappointed by its performance. To my surprise, it worked even better than the Fein vacuum and at a much lower price point.

rigid vacuum
I was surprised how well this Ridgid vacuum effectively contained the sanding dust.

Once the floors had been sanded down, it was finally time to start finishing with tung oil.

wood entry tile
Front entry transitioning to hardwood flooring.

Finishing the Floors with Tung Oil

Before we started the tung oil we made sure to tape edges where the wood met tile, mainly to keep clean-up to a minimum, but to also protect the grout from being darkened by the tung oil.

wood tile tape b4 tung
Utility room ready for tung oil.

Real Milk Paint, the company I purchased the tung oil from, has an excellent how-to video on doing wood floors:

We used close to a 50/50 mix of tung oil and citrus solvent, with just slightly more citrus solvent added to encourage deeper penetration of the tung oil.

My ‘helpers’ enjoyed doing the first coat with me in each room since there was such a dramatic color change as the tung oil initially went down. The tung oil really makes the grain and all the color variation in the wood really come to life.

First, we brushed in from the perimeter edges several inches, before rolling the rest of the floor with a lambswool roller connected to a paint stick. We were careful to not get too far ahead of the roller with the cutting in, hoping to avoid any ‘flashing’ that could show up where these areas meet up once the floor was completely dry.

family rm 1st coat
Anita brushing in the edges before rolling out the remainder of the floor.

It was always exciting to watch this dramatic transition from light and dusty to amber, dark, and stunning.

starting in br closet tung
Beast helping me start in her bedroom closet.
tung oiling s's br
Making our way across her bedroom floor.

Close-up of the hickory as the tung oil is applied:

dry tung
Dramatic change in color as the tung oil is applied.

Making progress across the family room floor:

dry tung family rm
First coat of tung oil going down in the family room.

Once the floor had a full coat of tung oil applied, we waited about 45 minutes before looking for areas where the oil had completely soaked in — this was especially pronounced around the many knots in the wood.

kitchen wet stay wet
Family room coated with tung oil.

After waiting an additional 45 minutes, we hit these ‘dry’ spots again. Once another 45 minutes were up we then wiped down the floors with cotton rags, available in 20 pound boxes from a local paint store.

s's br just tung oiled
Floor rolled, waiting for the tung oil to soak in.

Typically the floors were completely dry within 24 hours, but sometimes we waited one more day before repeating the same process a second and final time.

br entry after tung
Following morning after first application of tung oil.

After two separate days of applying the tung oil in this way, the floor was finally finished and I was ready to move on to the next room.

s's br after tung
2nd bedroom ready for baseboard.

It does take quite a few rags to wipe the floors down properly. It’s also worth noting that we were extremely careful once we were done to dispose of the rags responsibly in order to avoid a fire from the oil-soaked rags — a more common occurrence than most people realize.

final wipe down in mbr
Anita doing a final wipe down in the master bedroom.

In fact, when we thought we were done wiping, we’d go back one last time, walking the floor with rags under our shoes to get the last bit of tung oil that was inevitably still oozing up out of the hickory.

kitchen family rm after 1st ct tung
Family room ready for second day of tung oil application.

Here’s a close-up after the first coat color change next to the kitchen tile. We really like the contrast between the warmth of the wood and the cool gray of the tile:

kitchen wood connection after tung
Family room meets kitchen tile.

We also used this tung oil process on our basement stairs, which had hickory treads, along with a landing covered in hickory installed diagonally like the rest of the flooring.

Paul, from Signature Stairs, was the salesperson for our basement stairs. He made measuring and ordering what we wanted very easy, and he even took the time to stop by right after the stairs were installed and immediately took care of a minor touch-up for us. We’ve been extremely happy with the stairs. In fact, they were so well built we’ve yet to have even a single squeak, which, when compared to our last home, is extremely impressive.

base stair steps after tung

Because of the amount of variation in the wood, it was a lot of fun playing around with how best to show off the darker pieces. I always tried to keep in mind where furniture would end up, saving the most dramatic pieces for those areas that would remain out in the open and highly visible.

mbr b4 tung
Main bedroom ready to be sanded.

And it was always exciting to see the transformation from unfinished to very rich looking as the colors in the wood popped after the application of the tung oil:

mbr after tung
Main bedroom after tung oil.

We really love the color variation from one board to another. The range of colors and textures in the grain is stunningly beautiful. Visually the floors run the gamut from what looks like pine, walnut, tropical hardwood, oak, maple, birdseye maple, some boards with insect damage and staining, to of course clear hickory.

“There are trees with gnarly barks and unique shapes that represent some of nature’s most engaging sculptures, for they are the perfection of imperfection.”

— Andrew Juniper, Wabi Sabi: The Japanese Art of Impermanence

This wide variety of colors and textures celebrates the full breadth of what the wood has to offer (as opposed to just clear grade), and it nicely adds to our overall Urban Rustic and wabi-sabi design aesthetic for the house.

Here are some close-ups of individual boards showing this wide variation in looks:

tropical
Some of the darker boards look like walnut.
orange w: insect
A few boards had this insect or worm hole damage, including some attractive streaking.
lighter almost pine
Waves reminiscent of end grain Douglas fir.
light w: staining
There were several boards with this dark streaking over a much lighter background, as if the wood had been exposed to fire.
brown light red
The darker colors ranged from this walnut brown (at left) to a much redder, almost exotic tropical hardwood color (on the right).
lightest
The darker pieces were nicely balanced by many other lighter, more natural toned boards.
close-up knot w: staining
Even the knots themselves can be quite dramatic in terms of colors and smoky looking swirls.
beetle pine
There were even a couple of boards that look very much like beetle kill pine.

The orientation of the flooring was installed going with the main direction of foot traffic so that it feels like you’re almost always moving with the pattern in the floor rather than against it. In order to maintain this feeling throughout the house, it required changing direction in a couple of areas, for instance, where the kitchen and family room transition to the bedrooms. In these areas I used a transition piece in the door jamb of each bedroom to mark the change in direction.

mbr cu floor color variation
Main bedroom complete. Ready to change direction into the family room.

When the flooring changes direction it makes for a dramatic visual accent as the contrasting angles meet up. Below is the same area shown above, now with the family room flooring installed (but unfinished) next to the tung oiled main bedroom flooring:

family rm mbr wd flr meet
Change in direction from the family room (on the left) to the main bedroom (on the right).

Living with Oil-finished Hardwood Flooring

The tung oil finish is definitely softer and more prone to damage when it is first put down than a floor covered in a clear coat would be. After move-in day, I definitely noticed some scuff marks but no major damage. Since then, the tung oil finish has been holding up well.

Granted, we take our shoes off when entering the house, which definitely helps to keep dust and dirt under control, particularly the grit that can scratch wood floors. It also helps that we keep all food and drink in the kitchen. But this would’ve also held true had we gone with a clear coat finish on the wood, so there was no change in our behavior required from our last house to this one.

There’s only been a couple of times that a significant scratch or dent required getting out the Timbermate wood filler, the orbital sander, and the tung oil. In these cases, it was much easier to repair these relatively small spots than it otherwise would’ve been had the same damage occurred under a clear coat.

Overall, the main advantage a natural oil finish has over any clear coat is the amount of texture in the wood grain that’s allowed to come through (especially when viewed on an angle), combined with a matte finish, so the wood tends to look much more natural and warmer looking than it would if covered by multiple coats of clear finish.

mbr bath wood transition
Transition between the main bathroom and bedroom.

Nevertheless, I don’t think I would use an oil finish if we had a large dog, or if we preferred to keep our shoes on all the time. Under those circumstances, I’m guessing you’d have to commit to an annual spot sanding and tung oil application, at least in high traffic areas, to keep up with the damage so that it didn’t become too unsightly.

Hickory meeting kitchen tile.

Whether using a natural oil finish, or a more common clear coat, it’s worth exploring the options, including coming up with a few sample boards just to make sure you’ll be happy with the final look. A website like Green Building Supply is especially helpful in this regard, as they offer several brands of each kind of finish in low or no VOC products.

finished floor variation

It’s also worth noting that the initial wide contrast between the lightest and darkest boards has mellowed over time, so although the contrast is still evident it’s not quite as dramatic as it once was when the tung oil was first applied. Even so, we’re extremely happy with how our wood floors have turned out, and we have no regrets in terms of our choice of wood species or the use of an oil finish.

Completing our Wall Assembly: Rockwool Batts, Intello, and Drywall

4

Insulation for Exterior Walls

Once Wojtek and Mark were done installing our continuous insulation on the exterior side of our Zip sheathing (4″ of Rockwool Comfortboard 80), including the first layer of battens (no more errant fasteners through the Zip to worry about), I was able to move inside and begin installing Rockwool Batts (R-23) in our 2×6 wall framing.

Once we had moved on from our first builder, and after reading up on the available options for insulation, we decided to invest in Rockwool insulation, both the rigid Comfortboard 80 on the exterior of our sheathing and the Rockwool batts for inside our stud bays. Although more expensive, particularly the Comfortboard 80 for continuous insulation (used rigid foam would’ve been substantially less expensive), we felt that many of its properties made it worth the added cost.

In particular, by helping our wall assembly to be vapor-permeable (or vapor open), we felt the Rockwool could help mitigate any mistakes, should they be made, in the wall assembly details. This being our first build acting as a GC, we wanted to add some margin for error wherever we could find it.

More details on our wall assembly and how we finalized details, including our desire to maintain a high level of IAQ, can be found here: Wall Assembly

For environmental reasons, one of our goals was to try and be as “foam free” as possible throughout the build. In addition, beyond just this issue regarding the use of foam (in all its forms: rigid board and sprayed varieties alike), there’s increasing awareness about the carbon footprint of our structures, not to mention the total carbon footprint of our daily lives.

At any rate, if I had it to do over, I would at least seriously consider using reclaimed rigid foam for our continuous insulation over the sheathing (both for the potential cost savings and its status as a reclaimed material otherwise headed for a landfill), understanding that it does reduce a wall’s ability to dry to the exterior. As others have noted, using reclaimed rigid foam in this way may be the best, or “greenest”, use of foam insulation until the construction industry hopefully moves beyond its use altogether as better options become more viable (e.g., wood fiber insulation).

Here are some resources for reclaimed rigid foam:

http://insulationdepot.com/

https://www.reuseaction.com/sales/foam/

https://www.greeninsulationgroup.com/

https://www.repurposedmaterialsinc.com/polyiso-insulation/

I would also consider using dense pack cellulose in the 2×6 walls instead of the Rockwool batts if I could find an installer I was reasonably certain could do the work properly. During construction it felt safer to use my own labor to install the Rockwool batts, thus avoiding the possibility of any gaps in the wall insulation. I was hoping to offset the cost of the batts with my free labor, plus I just enjoyed doing the work. Had we gone with the dense pack cellulose, it would’ve been something I couldn’t do on my own (no equipment or training).

lights on in base 4 rockwool
Basement ready for Rockwool batt insulation.

Installing the Rockwool batts is fairly easy and satisfying work. They’re much easier to work with than fiberglass batts, which are horrible on your skin and tend to flop around as you try to get them into place. While the Rockwool also produces some irritating fibers when it’s cut (and requires a dust mask like fiberglass), I found that a shower easily washed them away. Wearing long sleeves during installation also easily mitigates this issue.

base knee wall w: rockwool going in
Insulating the exterior wall in what will be the basement stairwell.

Also, the fact that the Rockwool batts have a friction fit means they don’t require any additional staples or netting to get them to stay put once installed.

Because of the friction fit, it’s also easy to tear off small pieces to stuff into irregular shaped voids should the need arise.

rim joist w: and w:out rockwool
Basement rim joist without and with Rockwool batt insulation.

Like the Comfortboard 80, the batts can have some variation from one piece to another, with a change in the amount of density clearly visible. With the Comfortboard 80, this was significant enough that we avoided using the worst pieces, meaning those with the least amount of density (these pieces felt thinner and sometimes even crumbly). Although this inconsistency was still present in the batts, I managed to use almost every piece, saving the least dense pieces for use in some interior walls for sound attenuation (more on this topic below).

base kneel wall corner rockwool
Corner of basement with knee wall and rim joists insulated with Rockwool batts.

Overall, we were happy with the Rockwool batts, and would definitely use them again should dense pack cellulose not be a viable option. They’re also ideal for a self-build since anyone who’s reasonably handy can install them should they have the time available during construction.

rockwool around base beam
Rockwool batts packed into gaps around the basement steel beam.

In conjunction with the Intello that would eventually be installed over the 2×6 framing members and the Rockwool batts, we also used Flame Tech putty pads to air seal behind every outlet and light switch box. I had seen them used in a Matt Risinger video for sound attenuation:

The other option would’ve been to use airtight junction boxes. Here are a couple of examples: Small Planet Supply and 475HPBS.

In order to limit issues with all the air sealing I was doing, I tried to stick with products my subcontractors already used everyday. As a result, since my electrician wasn’t familiar with airtight junction boxes, I opted instead to come in after he had everything installed and apply the putty pads. I found installing them to be straightforward and pretty quick.

box label putty pads

The putty pads are attached to release paper. Once the paper was removed the pads were easy to mold around each outlet and light switch box.

label putty pad
Acoustical putty pads purchased on Amazon.

Here’s a completed outlet box:

putty pad on outlet
Putty pad molded around every outlet and light switch in exterior walls.

The trickiest area to detail for the walls was at the ceiling and wall junction. In our case, the roof trusses sit on 2-2×6’s turned on their sides, which sit on top of the wall’s double top plate. The 2-2×6’s create space for our service cavity under the bottom chord of the roof trusses.

extoseal-encors-as-gasket
2-2×6’s on edge, sitting on double top plates. Extoseal Encors acting as gasket once taped from the exterior face of the Zip sheathing over the top of the 2-2×6’s, thus completing an air sealed connection between the exterior (Zip sheathing) and the interior before roof trusses are set in place. More details here: Roof Details

Before cellulose could be blown into the attic, we installed Intello to the bottom chord of the roof trusses. At all outside edges the Intello was carried from the roof trusses down over the double top plates of the walls, anticipating the Intello eventually being installed on the walls, which required a connection point between the Intello on the ceiling and the Intello on the walls.

ceiling-wall b4 Intello - Rockwool
Ceiling and wall areas before installing Intello on the bottom chord of the roof trusses and Rockwool batts in the walls.

After the Intello was installed on the ceiling, a service cavity (or service core, or service chase) was created with 2×6’s screwed to the bottom chord of the trusses through the Intello.

string between junction boxes to make sure they're straight
Service cavity with 2×6’s attached to trusses through the Intello. More info on the service cavity here: Ceiling Details.

This gap was going to be a dedicated space for lighting and the 3″ Zehnder tubes of our ERV (as things turned out, we didn’t end up needing this space for the Zehnder tubes).

bare trusses - intello - intello w: single layer CB 80 - service chase
Intello coming down from the roof trusses to cover the double top plates on the wall.

Before installing the Rockwool batts in the walls, I was also able to fill this gap created by the two 2×6’s on their side that sit on top of the double top plates with leftover pieces of Comfortboard 80. The first piece of Rockwool fit snug inside the gap, while the second piece was attached to the first with some plastic cap nails and the friction supplied by the 2×6’s forming the service cavity. Some additional holding power was added at the gable ends by utilizing drywall clips (visible in the photo below):

intello onto top plates
Connecting Intello to top plates with a strip of Tescon Vana tape, creating a clean and solid surface for the eventual Intello on the walls.

The drywall clips were helpful in lending support to drywall anywhere that adding solid blocking would be time consuming or a physical challenge.

nailer for ceiling drywall
These drywall clips worked great in places where the sheetrock needed additional support.

Even though we utilized a 12″ raised heel roof truss, and we had 4″ of Rockwool on the exterior of our Zip sheathing, it was important to fill this gap created by the service cavity to make sure our thermal layer was unbroken around the perimeter of the house (4″ Rockwool on the exterior, 5 1/2″ Rockwool in the stud bays). The outside edge of the roof truss is also the most vulnerable to ice damming, so having the 4″ of Rockwool Comfortboard 80 directly below this area where blown-in cellulose would be installed offers some additional thermal performance to the attic insulation.

Another view of this area where roof truss meets the 2-2×6’s standing on their side, creating a gap between the bottom chord of the roof truss and the top plates on the wall below.

sealed top of wall from inside
Roof truss on 2-2×6’s turned on their sides, which have been sealed with Pro Clima tapes. HF sealant completes the airtight connection between the Zip sheathing and the 2-2×6’s.

If I had it to do over, I would go with a 24″ raised heel truss, as this would offer not only significantly more R-value in this area (for relatively little expense), it would also make any inspection or repairs in this area much easier to deal with.

mbr w: rockwool in walls
Installing Rockwool batts in the walls of the Master Bedroom.

As each piece of Rockwool batt was installed, it was important to keep any butt joints between cut pieces tight together. Also, once each piece was snug inside the stud bay I finished by gently fluffing the outside perimeter edges so the Rockwool sat as flush as possible to the 2×6 studs, thus maximizing their R-value.

mbr rockwool complete
Master Bedroom ready for Intello on the walls before drywall gets installed.
family rm w: rockwool
Family room ready for Intello and then drywall.

Intello

With 4″ of Rockwool Comfortboard 80 on the exterior of our sheathing, the code specifies that we could’ve just used latex paint as our interior vapor retarder (Class III).

Again, to improve our margin for error, I felt like it was worth the added expense and time to install a smart vapor retarder (CertainTeed’s Membrain product would’ve been another alternative) to avoid potential issues with diffusion in the winter.

When I asked a question on GBA about this issue, the consensus seemed to be that the Intello, although technically unnecessary, was a nice bit of insurance.

It also added a final layer to all of the previous air sealing details. With redundant layers of air sealing, even if small areas experience failure over time, there are still other areas to back it up, thus maintaining our overall air tightness for the long term.

intello at frt dr basement
Intello installed in the basement stairwell by the front door.
finishing intello mbr
Intello in Master Bedroom nearly complete.

Sealing the Intello to the subfloor was one of the final air sealing chores of the build. It was deeply gratifying to finally get to this point, especially since drywall and then flooring were up next.

tescon on intello at subfloor
Intello taped to the subfloor with Tescon Vana tape.
intello tvana complete mbr
Intello complete in the Master Bedroom.

Thoughts on Advanced Framing Techniques

If I had it to do over, I would use less framing around windows and doors, along with using pocket headers instead of the more traditional insulated headers we ended up with. Pushing the header to the exterior sheathing would mean being able to insulate the pocket on the interior side with Rockwool or dense pack cellulose, rather than the rigid foam we ended up with (unfortunately, XPS in our case).

family rm w: rockwool
Family room ready for Intello.

Before we had to fire them, the two GC’s we were still working with as framing began were unfamiliar with advanced framing techniques, and they were already struggling to comprehend the many Passive House details in the drawings (not to mention many of the conventional details) so, as I’ve noted elsewhere, I had to pick my battles carefully.

Another change I would make would be at points where interior walls meet up with exterior walls. Rather than using ladder blocking to make the connection, which is still better than more traditional methods (creating a boxed in void that’s virtually impossible to insulate), I would utilize a metal plate at the top of the walls to make a solid connection. In addition to making drywall installation easier since it would create space between the two intersecting walls for sheets of drywall to be passed through, it would also make installing insulation, especially batt insulation, much more straightforward with clear and easy access (no horizontal blocking to get in the way).

intello at ladder
Intello at partition wall that meets the exterior wall (using ladder blocking).

A ProTradeCraft article discusses what builder David Joyce believes is ‘worth doing’ in terms of advanced framing techniques. Perhaps just as important, he points out what he believes can be safely ignored, or is just ‘not worth doing’ when it comes to OVE.

In this Matt Risinger video, architect Steve Baczek delves into some of the key components he uses to optimize advanced framing techniques:

In addition to the pocket headers, the idea of using header hangers instead of additional jack studs, seems to make a lot of sense.

And here’s a ProTradeCraft video regarding their own take on Advanced Framing:

One final change to our framing would be opting for 2-stud corners instead of the California 3-stud corners that we have. Although a relatively small change, I think a 2-stud corner is cleaner and allows for slightly more insulation in this vulnerable area.

Clearly each designer, architect, GC, or framing crew will have their own particular views on advanced framing, so there’s room to make individual choices without undermining the goal of balancing structural integrity with reduced energy demand. Local codes, along with the opinion of your rough framing inspector, will also have to be accounted for.

My guess is these techniques will continue to evolve, especially if specific products come to market to aid the process (i.e. reduce the amount of framing lumber required while ideally also lowering labor costs, all without negatively affecting the overall strength of the structure).

intello kitchen
Intello in the kitchen complete.

One final attempt at some additional air sealing was around outlet and switch boxes as they met up with the Intello. With a bead of HF Sealant, it was easy to make an airtight connection between the Intello and the box.

cu intello at outlet
Completing connections around outlet and switch boxes with HF Sealant.

At doors and windows, I finished these areas off with a strip of Tescon Vana tape, just as I had at the top and bottom of the walls.

intello complete br2
Completing Intello around a bedroom window.

Because corners tend to be problematic in terms of air leakage, I also added a dab of HF Sealant to these areas for the sake of some added redundancy.

lwr lft corn wdw w: intello & tape
Lower left corner of window with some added HF Sealant in the corner.
upper rgt corner wdw w: intello
Upper right corner of a window just before final piece of Tescon Vana tape is run across the top of the window frame, tying together the Intello and the light blue Profil tape that is air sealing around the window.

Sound Attenuation

Since we designed our home with a smaller than average footprint, incorporating many Not So Big House principles (roughly 1500 square feet for the main floor, with another 1500 square feet in the full basement below), one way to make the floorplan feel larger than it actually is was to provide some sound attenuation in key areas (we incorporated several other techniques to “expand” the feel of the floorplan that will be discussed in upcoming posts regarding interior design).

For instance, we installed the Rockwool in the long partition wall that runs east-west down the center of the floorplan. This wall helps define the barrier between public areas (kitchen and family room) on the south side of the home and the private areas (bathrooms and bedrooms) on the north side of the home.

We could’ve used Rockwool Safe ‘n’ Sound, but at the time, during construction in the fall of 2017, it was a special order item in my area, whereas the batts were already in stock, both for my main 2×6 partition wall, a 2×6 plumbing wall, and the remaining 2×4 walls that we felt could benefit from the Rockwool.

In the photo below, the Rockwool in the main east-west partition wall is covering the refrigerant and drain line for one of our three Mitsubishi heat pump heads, along with the usual electrical conduit for outlets and light switches.

rockwool 2nd br entry hall
Rockwool added to some interior walls for sound absorption, thus reducing unwanted sound transmission between certain spaces.

Here’s another view of this partition wall, this time from the opposite side inside the second bedroom:

rockwool 2nd br interior side
Same section of east-west partition wall from inside the second bedroom.

We also added Rockwool to the wall that connects the master bath to the 2nd bedroom bath, and between the 2nd bath and 2nd bedroom. The Rockwool was even added to the wall between our kitchen and utility room, where we have our washer and dryer, in the hopes that it would limit the amount of noise coming from the machines (which it thankfully has).

rockwool bath walls
Rockwool in bathroom wall around main waste stack.

Although this doesn’t make for a totally sound proof connection between spaces (we weren’t prepared to take things that far — roughly equivalent to air sealing a Passive House in the amount of detail required), the ability of the Rockwool to significantly muffle sound between rooms is quite impressive and, for us at least, well worth the effort and added expense.

rockwool kitch - utility
Rockwool in the wall between the kitchen and utility room.

For instance, while standing in the master bathroom, should someone be running water or flushing the toilet in the 2nd bathroom directly on the other side of the wall, the majority of the sound that reaches your ear comes by way of the master bedroom doorway, not through the wall directly. Out of curiosity I tested this idea with music playing on a portable stereo in the 2nd bathroom with the same results — sound through the wall is dramatically muffled, while the same sound that easily travels out of the bathroom and makes it way via the bedroom doorway is crystal clear. With the door to the 2nd bathroom and our master bedroom door closed, this same sound is obviously further reduced.

It’s also nice to watch TV in the family room and know that as long as the volume is at a reasonable level you’re not disturbing anyone trying to sleep or read in the two bedrooms. This kind of sound attenuation also adds a level of privacy to the bathrooms while they’re in use.

And, again, it’s not that no sound is transmitted from one room to another, rather it’s almost entirely limited to doorways, thus significantly reducing the overall impact of the noise that is transmitted. In other words, our goal was rather modest, we were just after significant sound absorption, not sound proofing (e.g. the level of noise cancellation required in a professional recording studio or a high-end home theater room).

As a result, I would definitely use Rockwool for sound absorption again. In fact, I can’t imagine going without this kind of sound attenuation (or something akin to it using other products or techniques outlined in the videos above) now that we’ve been able to enjoy it in our new home. It effectively prevents the issues often associated with so-called “paper thin” walls.

Arguably, addressing this issue of unwanted sound transmission is even more important in Passive Houses or high-performance homes that are already much quieter than conventional homes because of the extensive air sealing and well above code levels of insulation. In our own case, outside noises either disappear entirely or are significantly muffled — this includes a commuter train a couple of blocks away.

As a result, any noises within the home itself become much more pronounced since they don’t have to compete with the typical noises coming from outside the home. For instance, when we first moved in the fridge in the kitchen was easily the most obvious, consistent sound in the house. After a couple of weeks it just became background noise we’ve grown to ignore, but it was surprising just how loud it was initially, especially our first few nights in the home when everything else was so quiet.

In addition to excessive air leakage and obvious temperature swings between rooms, along with poorly sized or placed window layouts, the lack of any sound attenuation between rooms is one of the issues we notice the most when we’re inside more conventionally built homes. Much like all of the conveniences associated with a modern kitchen, it’s easy to take something like effective sound attenuation for granted until you’re required to go without it (e.g. in the case of kitchens while on a camping trip or waiting for a kitchen to be remodeled).

With all of the Rockwool batts in place, and the Intello installed over the exterior walls, drywall could finally go up.

Drywall

We went with USG 5/8″ EcoSmart drywall (GBA article on EcoSmart). We chose the 5/8″ over 1/2″ mainly for added durability and some slight sound deadening between rooms.

I had read about Certainteed’s AirRenew drywall, but it sounded like the only VOC it absorbed was formaldehyde, which, if I understand the issue correctly, can be safely avoided with the use of appropriate cabinets and furniture. If memory serves, AirRenew works by utilizing a compound similar to triclosan, meaning a biocide, which some believe can have potentially serious health effects. It’s not clear to me, even now, whether the use of AirRenew drywall makes sense, or exactly what compound (or series of compounds) are utilized to absorb the formaldehyde since Certainteed has remained silent on this point, claiming the information is proprietary. Nevertheless, it has a Declare label, so ILFI must believe it’s reasonably safe to have on painted ceilings and walls.

At any rate, we wouldn’t be bringing in any new furniture that would have elevated levels of VOC’s (including flame retardants) once construction was complete. Since our last house was significantly larger, roughly 2,800 sq. ft., it was fairly easy to downsize, donating or giving away what we couldn’t use in our new house, while holding on to our favorite and most useful pieces. It also helped that we never really filled up our last house (e.g. we never got around to purchasing a formal dining room set), so we didn’t have as much “stuff” to discard as we might have.

Moreover, by being mindful of every finish we create or use (primers, paints, wood flooring, grout sealer, caulks and sealants, kitchen cabinets etc.), along with any other products we might bring into the new house (e.g. surface cleaners, new furniture, fabrics, even perfumes and colognes, etc.), we’re hoping to maintain a high level of IAQ.

The International Living Future Institutes’s Red List and their database of Declare products were a big help to us, even though we’re not pursuing any kind of certification with them. The Greenguard certified label was also helpful, in particular when it came time to choose tile and grout.

By consciously choosing every product and material that comes into the home, it’s possible to at least reduce our exposure to harmful VOC’s and chemicals. While still imperfect (Who can you trust?), these kinds of programs do allow designers and homeowners to take some control over the environments they’re creating and living in, which is empowering to a degree. Far better if the US regulatory bodies operated under a precautionary principle model when it came to industrial products.

Frankly, in a rational system, one that was truly looking out for the best interests of consumers, this kind of research — time consuming and frustrating busy work to put a finer point on it — would be considered laughable if not horrifying. In a rational system it would be safe to assume that any product for sale, apart from some careful instructions on their use and disposal, would be safe to have inside your home without having to worry about short or long term health implications.

Nevertheless, if unintended health consequences are to be avoided during a renovation or a new construction build, consumers have little choice but to do the necessary homework (or pay someone else to do it for them) and be as thoughtful as possible with their selection of materials.

drywall family rm
Kitchen and family room after drywall was installed. Ready for primer, paint, and flooring.

Now that all of the elements of our wall assembly were complete, it was time to have some fun with final finishes: flooring, wall colors, wood trim, doors, kitchen cabinets…

Blower Door (Air Sealing #9 )

4

When it was time to schedule our blower door test we considered using Eco Achievers, but we only knew about them because they’ve worked extensively on projects for our original builder, Evolutionary Home Builders. We decided the potential awkwardness, or even a possible conflict of interest, wasn’t worth pursuing their services. An example of guilt-by-association I suppose, one that is probably unfounded but, nevertheless, the strong affiliation with our original builder made it difficult for us to reach out to them for help. They also hired one of Brandon’s former employees (this employee was nothing but nice and professional towards us as we were deciding to part ways with Brandon), which would’ve only added another layer of awkwardness to the situation.

Unsure how to proceed, I looked online and found Anthony from Building Energy Experts. He was able to come out and do a blower door test for us, helping me hunt down a couple of small leaks, so that we ended up at 0.34 ACH@50 for this initial test.

Here’s a Hammer and Hand video discussing the use of a blower door:

On a side note: all of the Hammer and Hand videos, along with their Best Practices Manual, were incredibly helpful as we tried to figure out all the Passive House details related to our build. It’s no exaggeration to say that without Hammer and Hand, the Green Building Advisor website, BSC, and 475 HPBS, our build would’ve been impossible to accomplish on our own. I owe an incredible debt of gratitude to all of these great resources who invest valuable time sharing such a wealth of information.

Below is a Hammer and Hand video noting the importance of properly detailing corners to avoid air leaks:

Because of this video, I sealed all of my corners for the windows and doors like this:

HF Sealant in corners b4 blower door
Adding Pro Clima HF Sealant after completing taping of the corner, just for added insurance against potential air leakage.

I also added some HF Sealant to the lower portion of the windows, since some air leakage showed up in this area with Anthony where components of the window itself come together in a seam.

sealant on wdw components junction
Seam near bottom of window where components meet — sealed with HF Sealant.

The areas where components come together often need special attention.

close up corner and wdw components seam w: sealant
Close-up of this same area — seam in components sealed, along with the bottom corner of the window and the gap between window buck and window.

Even with layers of redundancy in place, in the picture below there was a small air leak still present at the bottom plate – sub flooring connection. A coating of HF Sealant easily blocked it.

Once the stud bays were insulated (after most of the siding was up), the interior walls would eventually be covered with Intello (I’ll cover the details in a future post on interior insulation), adding yet another layer of redundancy for mitigating potential air intrusion.

area of kitchen sill plate leakage
Area of kitchen sill plate leakage.

Anthony didn’t have any previous experience with a Passive House build, so it occurred to me that it might be beneficial to reach out to Floris from 475 High Performance Building Supply (he had already done our WUFI analysis for us), and Mike Conners from Kenwood Property Development to see if there was someone locally who did. Mike is a Passive House builder in Chicago who had already helped me out with some Rockwool insulation when we came up short earlier in our project (the two GC’s we fired repeatedly struggled with basic math), and he was very nice to take the time to answer some other technical questions for me as well.

Both, as it turned out, ended up recommending that I contact Steve Marchese from the Association for Energy Affordability.

Steve would eventually make three trips to the house, doing an initial blower door test after the structure was weather-tight and all the necessary penetrations had been made through our air barrier, a second test after exterior continuous insulation was installed, and a final test after drywall was up to ensure there hadn’t been any increase in air leakage during the final stages of construction.

Steve starting blower door test
Steve setting up the blower door for his first test.

Following Passive House principles for our build, we also followed the same protocols for the blower door tests: Blower Door Protocol

With the structure under pressure from the blower door fan, Steve and I walked around the house while he used a small smoke machine in order to try and find any leaks that I could then seal up.

Steve testing window gasket
Steve starting at the windows. Here testing a window gasket for air leakage.

The gaskets around our windows and doors proved to be some of the weakest areas in the house although, comparatively speaking, it was inconsequential since the overall air tightness of the structure was fairly robust (favorite word of architects).

Steve showing impact of unlocked window
Steve showing me the impact a window in the unlocked position can have on air tightness. The gasket, ordinarily squeezed in the locked position, works to bring the sash and the frame tightly together.
Steve smoke at family rm wdw
Looking for areas around the windows that might need adjusting or additional air sealing.

For instance, even though no substantial air leakage showed up around this kitchen door, during our first winter this same door eventually had ice form outside at the upper corner by the hinges, on the exposed surface of the gasket where the door meets the frame.

Steve at kitchen door

After figuring out how to adjust the door hinges, there was no longer any ice showing up this winter, not even during our Polar Vortex event in late January.

Much the same thing occurred around our front door as well, with the same solution — adjusting the hinges to get a tighter fit at the gasket between the door and the frame.

Steve testing attic hatch
Steve testing the attic hatch for any air leakage.

Steve was nice enough to go around and methodically check all the penetrations in the structure.

Steve testing plumbing vent in kitchen
Steve testing for air leaks around the kitchen plumbing vent and some conduit.
Steve testing for air leaks @ radon stack
Steve testing for air leaks around the radon stack.
Steve @ radon stack close up
Close-up of radon stack during smoke test.

There was one area in the guest bathroom where the Intello ended up getting slightly wrinkled in a corner during installation. With Tescon Vana and some HF Sealant I was able to address it so nothing, thankfully, showed up during the smoke test.

Steve testing wrinkled area of Intello
Steve testing area of Intello that I inadvertently wrinkled during its installation.

After looking around on the main floor, Steve moved down into the basement.

Steve testing for air leaks @ main panel
Checking for leaks at the main electrical panel.
Steve testing for air leaks @ main panel exit point
Checking for leaks at the conduit as it exits the structure.
Steve testing for air leak @ sump pit cap
Looking for air leakage around the sump pit lid.

The lids for the sump pit and the ejector pit were eventually sealed with duct seal putty and some Prosoco Air Dam.

Steve testing for air leaks @ ejector pit
Testing the ejector pit for air movement.
Steve testing for air leaks @ Zehnder exit point
Checking for air leakage around one of the Zehnder ComfoPipes as it exits the structure.
Steve testing for air leaks @ pvc:refrigerant lines
Looking for air leaks around the heat pump refrigerant lines as they exit the structure.
Steve smoke at sump discharge
Checking around the penetration for our sump pump discharge to the outside.

Before the second blower door test, I was able to add some duct seal putty to the lids of the sump and ejector pits.

ejector pump lid w: duct seal
Ejector pit lid with some duct seal putty.

Below is a copy of Steve’s blower door test results, showing the information you can expect to receive with such a report:

Final Blower Door Test Results

For the last two tests Steve used a smaller duct blaster fan in order to try and get a more precise reading for air leakage.

Steve at front door
With Steve just after the initial blower door test was complete.

Steve would be back two more times — once before drywall, and once after drywall — just to ensure we had no loss of air tightness develop in the interim stages of the build (especially after continuous exterior insulation with furring strips were installed).

Here are the final figures noting where we ended up:

0.20 ACH@50 and 106 cfm@50

We are well below Passive House requirements (both PHI and PHIUS), so there was a great sense of relief knowing that all the time and effort put into air sealing had paid off, giving us the tight shell we were looking for. Even so, it was still pretty exciting news, especially for a first build.

And here’s an interesting article by 475 HPBS regarding the debate over how air tightness is calculated for PHI vs. PHIUS projects, and the potential ramifications:

Not Airtight

HVAC Part 1: Zehnder ERV

36

DIY Installation

Building with Passive House principles in mind, we knew that, in addition to maintaining a tight building envelope, and incorporating substantial amounts of insulation around the structure, we also needed to install continuous mechanical ventilation in order to have adequate levels of fresh air, not to mention the ability to expel stale air.

We also needed our system, either an HRV or an ERV, to be highly efficient, meaning it could hold onto some of the heat in the conditioned air even as it introduced fresh and, oftentimes, cold air by means of heat exchange as the two streams of air (fresh and stale) passed by one another inside the main unit (without actually mixing together).

After researching the many options, we ended up going with Zehnder’s ERV, in our case, the ComfoAir 350 (the various Zehnder units are based on overall cfm demand of the structure).

We only considered two other brands for our mechanical ventilation (HRV vs. ERV):

UltimateAire

and

Renewaire

In all the research I did prior to construction, these three brands showed up the most in the projects I read about.

Here’s a good debate on the Green Building Advisor website discussing brand options: ERV Choices

Another interesting option would be the CERV system. Because they’re a smaller, newer company, we didn’t feel comfortable pursuing it, but it does look like a viable option worth considering if building a Passive House or Pretty Good House.

I was also familiar with Panasonic units, but I had always read that they weren’t efficient enough in terms of the heat exchange function (or heat recovery) to seriously consider using it in a Passive House or a Pretty Good House in a predominantly cold climate region like ours, here in the Chicago area.

Our Zehnder ComfoAir 350 is said to be 84% efficient in terms of heat recovery (the same principle applies in summer, only working in reverse, when you’re trying to hold onto cooled, conditioned air). Based on what I read during the design phase, the consensus seemed to be that, although more expensive, the Zehnder has a strong track record of performance and durability.

The Zehnder also came with its own ductwork, which we knew would simplify installation, allowing us to do it ourselves, rather than hire someone else to come in and run more conventional ductwork through the house (conventional ductwork would’ve taken up a lot more space as well). Even though the unit itself was more expensive, we thought we could offset some of the total cost for a ventilation system by installing the Zehnder ourselves, thereby saving some money on labor costs.

As far as the ERV/HRV debate for Northern US states, we decided to opt for the ERV because it was supposed to help us hold onto some humidity in winter months, especially important when most structures in the Chicago area are exceedingly dry for most of the winter (and our winters are long). Although I read repeatedly during the design stage that ERV’s can also help control summer outdoor humidity entering the house, this has not been our experience at all. In fact, the ERV seems pretty useless in this regard (more on this below).

The system quote we received was easy to understand, and Zehnder was nice enough to essentially design the system, both in terms of layout (i.e., where we should put all the supply and exhaust points), along with the quantity, or cfm’s, of air for each point. In the end, after commissioning the unit, the system should be balanced, meaning the unit should be bringing in as much fresh outdoor air as it is expelling stale indoor air.

As far as Zehnder units being DIY friendly in terms of installation, in our opinion, this is highly debatable since the installation manual is far from comprehensive. Our installation manual ended at physically installing the main unit on the wall. Not very helpful.

Without a detailed installation manual showing step-by-step how all the individual pieces fit together, you end up with a pile of what initially seems like random parts.

zehnder pile of parts
Everything we need to install our Zehnder ERV. Most of the smaller components are still in the many cardboard boxes off to the right.

This was incredibly frustrating, especially since Zehnder units are purchased at a premium when compared to other competitive brands, and with the expectation of durability and design precision. It never occurred to me to ask before purchasing the unit for an installation manual, since it seemed a fair assumption that no one would sell a premium product without detailed instructions on how to put it together.

We were only able to proceed because of numerous online videos, googling Zehnder unit photos, and by staring at and experimenting with the various parts to try and figure out how it all was supposed to come together. It was an unnecessary and torturous puzzle that shouldn’t have needed solving, and it wasted hours of my life that I’ll never get back. If you do an internet search and type in: “google review Zehnder America” the experience Sean Hoppes had with his installation wasn’t all that different from ours.

Looking on the current Zehnder website (February, 2019), I can’t find a more detailed set of instructions, either written or in a video format, which is disappointing. This seems like a pretty glaring oversight on Zehnder’s part, and one that should be remedied immediately.

Having lived with the unit for almost a year now, overall we’re happy with its performance, and we feel like we could install one fairly easily now that we’ve gone through the entire process, so it’s a shame we can’t say only nice things about the product simply because the installation manual was so limited or, more to the point, non-existent.

With each video and each photo, it was possible to glean one more crucial nugget of information, which took hours, whereas a detailed written manual or a step-by-step video would’ve made the process straightforward, and by comparison, frustration-free.

The videos below were especially helpful, but, nevertheless, they still leave out quite a bit of pertinent information necessary for any first-time installer (especially regarding all the parts that need to be installed on top of the main unit):

Unless there are no DIYers in Europe installing these units, and this is the expectation Zehnder has for its units both for overseas and here in the US, not having a comprehensive installation manual makes no sense. I’m not sure how even a licensed and competent HVAC installer would fare much better without direct experience installing the units. My guess is they would be searching online for missing info much like we did.

Once we got the main unit installed on the wall, and we figured out how all the parts fit together on top of the unit, by the time we got to installing the small, white 3″ ComfoTubes and the large, gray ComfoPipe, the process became much easier.

main unit attached to basement wall
Mounting the main unit to the basement foundation wall with Tapcon concrete screws.

In regards to the gray ComfoPipe for the main fresh air supply and the main exhaust, both of which pass through the wall assembly, we found it more effective to put individual sections together on the floor, and, once fully connected, we marked the points at which the pipes met with a permanent marker.

marking comfopipe w: sharpie
Marking sections of connected ComfoPipe with a Sharpie while they’re on the floor ensures a tight fit once a connection has been made off the floor.

If you try to piece the tubes together one piece at a time in mid-air it’s much harder to gauge when the pieces are actually tightly put together. With each connection point of pipe clearly marked with a Sharpie, it gives you an obvious goal to shoot for once you have the pipe almost in its final position. More to the point, it’s obvious when sections of pipe get out of alignment, or the connection isn’t nearly tight enough — it’s much more difficult to accurately gauge if only going by “feel” once the sections of ComfoPipe are off the floor.

drilling hole for Zehnder exhaust
Making initial cut in the Zip sheathing.

Using a piece of ComfoPipe, we outlined on the interior side of our Zip sheathing exactly where we wanted the pipe to end up (trying to get as close to center as possible — makes air sealing around any penetration much easier). After a hole was cut with a 3″ hole saw, we cut out the rest of the hole using a jigsaw.

hole in Zip for heat pump pvc
Hole cut and ready for the ComfoPipe.
hole set-up for comfopipe
Hole made in our Zip sheathing, ready for the ComfoPipe from outside to make a connection with the section inside.
ext - comfo pipe going thru zip into basement
Ready to push the ComfoPipe into the house from outside to make the connection inside.
Zehnder chipmunk's back
Chipmunks are back.

Once we started using the Sharpie, it was relatively easy to get all the ComfoPipe installed and air sealed around the Zip sheathing.

comfo pipe thru zip
Making the connection between inside and outside.
setting up comfo pipe
Adding a Roflex gasket to make air sealing much easier.
comfo pipe sealed int.
ComfoPipe air sealed on the interior side with Roflex gasket and Tescon Vana.
close up comfopipe sealed
Close-up of the ComfoPipe air sealed at the Zip sheathing.
installing comfo pipe next to main unit
Finishing up the last sections of ComfoPipe as they leave the main unit.

Following the directions, we kept the ComfoPipe exit points for supply and exhaust more than 10′ apart outside, where they enter and exit the structure, in order to avoid any possibility of the two air streams mixing, which would undermine the effectiveness of the system.

comfopipe ext sealed and covered
Repeating the same air sealing process on the exterior for the ComfoPipe, adding black garbage bags over the opening with rubber bands to keep out dust, dirt, birds, and any critters that might otherwise try to enter the structure during construction.

On the outside, we made sure to extend the ComfoPipe out farther than we needed, giving us some leeway once insulation and siding were installed over the Zip sheathing. This allowed us to cut the ComfoPipe back to the proper depth before installing the permanent covers supplied by Zehnder.

comfo pipe ext close up sealed
Close-up of ComfoPipe as it exits the structure (before insulation, furring strips, siding, and its final cover).

As far as the white tubing is concerned, we really enjoyed how easy it was to put the 3″ ComfoTubes together.

During the design phase, and even after we brought the Zehnder unit to the job site, we always intended to place the diffusers for supply and exhaust points on ceilings. But after really looking at all the cuts in our ceiling service chase that would be required to make this happen, we decided to opt for placing all of them on walls instead.

It proved to be one of the better decisions we made during construction. Not only did we avoid having to make many cuts in our ceiling structure, which would’ve meant a struggle to appropriately map them out around conduit, ceiling lights, and plumbing vents, it had the added benefit of making it much easier to do ongoing maintenance at the diffusers, mainly checking on and cleaning filters, once we moved in.

cone diffuser filter
Cone shaped filter for exhaust diffusers (bathrooms, kitchen, laundry room, and basement in our case).

In fact, during commissioning, our Zehnder rep told me they have issues with homeowners not keeping their exhaust diffuser filters properly cleaned, effectively undermining the efficiency and overall performance of the units. This is understandable if the diffusers are on ceilings, whether at 8′ or 9′. It would be easy to forget about them, or even if you did remember, one can understand the reluctance to drag out a 6′ step ladder every time they needed to be cleaned. We were also told that placement of the diffusers is extremely flexible — almost anywhere can work (check with Zehnder directly just to make sure your proposed placement will work).

inside diffuser filter
Diffuser filter in bathroom after about a month. Once all the construction dust settled down from completing interior finishes, these filters don’t get dirty nearly as quickly as they once did — in other words, this isn’t bad at all.

By keeping them around 7′ off the finished floor, it’s easy for me to check and clean the exhaust diffuser filters on a regular basis (1-2) times a month. I always have 2 sets of filters, so it’s easy to remove the dirty ones, put in clean ones, and then rinse and dry out the dirty ones.

Once we decided to go through walls (both 2×6 and 2×4 framed walls), it was just a matter of deciding where in each wall we wanted the diffusers to be placed, and then cutting the corresponding hole through the wall’s bottom plate and the subfloor — being careful to check, and re-check, in the basement for any floor joists, plumbing, or electric conduit that might be in the way.

For bathrooms we placed the diffusers between showers and toilets, slightly cheating towards the showers to ensure maximum moisture removal.

changa drilling for tubes
Apparently cutting the holes through the floor looked like fun since my wife was happy to take over this chore for me. The DeWalt we were using worked great until it crapped out on us a couple of holes short of finishing. We definitely noticed a difference going back to a normal drill and hole saw set-up.

At the unit itself, Zehnder supplied us with blue (fresh air) and red (stale air) tags, to mark each ComfoTube as it leaves or returns to the main unit. This should make any potential maintenance or repair issues in the future easier to resolve, as well as helping to avoid confusion as you set in place each pipe at a diffuser.

first few return tubes are in
Attaching the white ComfoTubes to the main unit, carefully labeling each pipe for future reference.
main unit w: exhaust tubing installed
ComfoTubes being installed at the main unit.
top of silencers #2
Close-up of the top of the main unit, as ComfoTubes are being installed.
Sydney helping us
Sydney, one of our former Excel students, was nice enough to stop by and help us pull the ComfoTubes from the basement up to the first floor.
OB helping us pull and set-up the tubes
OB was also nice enough to come back to help us push and pull the ComfoTubes into place for the diffusers.
spaghetti
Pulling more tubing than we need up to the first floor. Later it’s cut back to properly fit to the various diffuser boxes.
setting up a port
Putting together a diffuser box.

Since we’re leaving the basement ceiling unfinished, it’s an ideal place to see how all the components come together: ComfoTubes meet at the diffuser box, along with the final cover for the diffuser, in this case for supply air. As you can see in the photo, there’s plenty of room in the metal tube of the diffuser box for deciding exactly where to cut it off in order to establish the finished height for the diffuser cover. In the basement we left them at their full height since there didn’t seem to be much incentive to cut them back.

basement supply diffuser
Basement diffuser box with attached ComfoTubes and final diffuser head (supply in this case).
laundry rm zehnder
Exhaust point in utility room with only one ComfoTube.

All of the diffuser boxes required at least two ComfoTubes, except for the laundry/utility room, which only required one. Using one of the supplied black plastic caps made it easy to block off one of the outlets in the diffuser box. These black caps are also handy when pulling the ComfoTubes around into position since they help to keep out any construction debris.

laundry rm exhaust
One outlet in the diffuser box is blocked off for the laundry room since we only required 12cfm for this area (12cfm per opening/ComfoTube).

Our kitchen required the most cfm’s, at 36, so it required a special diffuser box and three ComfoTubes.

kitchen octopus
3-hole diffuser box (36 cfm) for kitchen exhaust.

Again, since we didn’t place it in the ceiling, we put it across the kitchen, basically on a diagonal from the stove. So far we haven’t had any issues with cooking grease or odors, and our range hood (recirculating) seems to be doing its job just as well.

sunlight coming down comfo tubes
Sunlight coming down the ComfoTubes into the basement from the main floor.

Using scrap lumber, we were able to give each diffuser its proper stability in the wall cavities. Although the mounting hardware for each diffuser box seems rather fragile, we managed to avoid any issues.

Applying a bit of hand soap around each opening in a diffuser box made getting a solid fit between the ComfoTube, the black O-ring, and the diffuser box fairly straightforward.

connecting tube in kitchen
Attaching ComfoTubes with black O-rings and sliding clips on the diffuser box.
tubes for octopus in kitchen
ComfoTubes for kitchen exhaust going through the subflooring and into the basement.
black 0 ring
Putting the black O-ring on the ComfoTube.

It was also fairly easy to get each ComfoTube exactly where we wanted it. Since they’re so small (at least compared to traditional sheet metal ductwork), the tubes are easy to manipulate and move around, whether over a basement beam, around plumbing, electric, or any other structural component that’s not easily relocated. As long as you don’t need to make a short 90° turn, the tubes are easy to work with, so I imagine they would be ideal for renovation work in older homes.

long shot before tightening comfo tubes
It was fairly easy to put the ComfoTubes exactly where we needed them to go.

With most of the ComfoTubes in place, we just needed to add a couple of walls in the basement before finishing up the last few ComfoTubes.

raising basement wall w: Jesus and Eduardo
Jesus and Eduardo were nice enough to come back to help me put up a couple of basement walls.

Once all the ComfoTubes were installed at all the diffusers and at the main unit in the basement, we were able to pull all the lines tighter for a less messy final installation.

spaghetti comfotubes
Before pulling the tubing tight.

Using 2×4’s, we created a little window for the ComfoTubes to pass through under the floor joists. This structure helped to get the ComfoTubes moving away from the main unit in an orderly way that made it much easier to organize all the tubing once it was all installed:

zehnder installed w: tubes
All the ComfoTubes pulled tight, up by the floor joists, kept in place with some plumbing hangers.

Using plumbing hangers also kept the ComfoTubes under control and organized.

hanger straps for comfo tubes
Straps used to corral the sometimes unwieldy ComfoTubes, which can resemble spaghetti if left unorganized. They also worked well at stabilizing the gray ComfoPipe.

The commissioning of the unit, after drywall was complete, was fairly easy and straightforward, apart from a couple of wiring and electrical issues that had to be dealt with by phone with a Zehnder rep beforehand. And ordering filters from the Zehnder website has also been a straightforward and painless process so far (they’re not cheap, but they do seem to be highly effective).

The only issue we’ve really noticed with the unit is during summer when outdoor humidity levels are high. Since the ERV is constantly running, there’s no way to avoid bringing in some humid air in the summer.

And, unfortunately, it’s enough so that our Mitsubishi heat pump set-up (a future Part 2 of 2 for HVAC details) can’t properly get rid of the excess humidity either, even as it keeps the interior more than adequately cooled. We tried setting the heads to dehumidify, but they just dropped the temperature (almost to 60° F) without budging the humidity in the house very much — the rooms were freezing and clammy. As noted earlier, an ERV just can’t handle elevated levels of humidity in the summer on its own.

By having meters in various areas of the house it’s easy to see when humidity levels become a problem (we’ve been happy with our AcuRite gauges). Last summer our solution was to buy a couple of small dehumidifiers, one for the first floor and one for the basement. They worked, but they also ate up a lot of energy. Setting the Zehnder fan speed to LOW seemed to help somewhat, but not enough to avoid using the dehumidifiers. This summer we’re going to try a stand-alone Ultra-Aire whole-house dehumidifier, which should use less electricity, and it should perform at least as well, if not better, at removing excess humidity.

Having read that anything above 60% indoor humidity can be problematic, especially in tighter, high-performance homes, it was disheartening to see the numbers move towards 70% in early summer. This is what prompted the purchase of the dehumidifiers.

From everything I had read during the design phase regarding Passive House, I knew indoor humidity in the summer could be a slight issue, but having experienced it firsthand, it now seems obvious that incorporating a dedicated dehumidifier in any structure that will see elevated levels of summer humidity, even if it’s only expected to last for just a few weeks, is simply a necessity. Based on what I’ve read recently, it sounds like Passive House designers, who were already doing this for Southern US states, are moving towards doing it in states much farther north. Presumably this would also hold true for anyone designing a Pretty Good House as well.

Granted, 60-70% indoor humidity (or even higher) for a couple of weeks probably won’t ruin any structure, but for us, at least, keeping it in the 50-60% range during the hottest days of summer not only gives us some added peace of mind, regardless of the hit we’ll take in terms of overall energy use, but it’s also an issue of comfort (I grew up in a house without air conditioning and still have vivid memories —all of them bad — of enduring hot and humid summer days and, even worse, long summer nights).

Much like the initial complaints of overheating, due to excessive or improper placement of glazing, especially on southern facades, this issue with excessive humidity seems to be part of the evolution in understanding how Passive Houses, or high-performance homes generally, actually work in real-world conditions. Although the concept has been around since the 1990’s, anyone building to or even just towards the Passive House standard should know they are guinea pigs to some extent, no matter how well established the idea may be in building science terms.

In the winter, we’ve had no issues. When temperatures fall below 20° F, we set the Zehnder to LOW, in the hopes that it will reduce demand on the heat pumps slightly, and it seems to hold onto humidity somewhat when the cold air being introduced would otherwise be excessively dry. Indoor humidity levels have been pretty consistent: above freezing they typically stay around 40%, and when temperatures plummet towards zero or below they’ve still stayed in the 30-35% range. We’ve rarely seen indoor humidity drop below 30%, even on the coldest days, which definitely makes a difference on overall comfort levels. I’ve also noticed that wood flooring and wood trim doesn’t shrink nearly as much as it did in our last, conventionally built home.

Also, even when we experienced record low temperatures last month (January, 2019), hitting -24° F without windchill, the Zehnder kept on running without any issues. As far as we know, it never shut off to try and protect itself from the cold (our mini-split system did, but more on that later). The product literature is somewhat vague, only noting that low temperatures could cause a unit to shut off, but it’s unclear at exactly what temperatures or what combination of other environmental conditions might cause this to happen.

Most people either tape or use sealant on the gray ComfoPipe seams to block air leakage. During our blower door test no air leakage showed up, even with a smoke pen test. Nevertheless, during our recent cold snap some frost was evident on the ComfoPipe seams, so I’ll eventually caulk these seams with Pro Clima’s HF Sealant, since there must be some air leakage, be it ever so minor.

In terms of the boost function, when turned on it pulls from all the exhaust diffusers, not just a particular bathroom or the kitchen. Again, for the kitchen, even if we’ve been roasting garlic or cooking something else that’s equally pungent, by the next morning any cooking smell is usually completely gone. There’s never been any lingering smells emanating from the kitchen.

For the kitchen, when you want to utilize the boost function you just set the ComfoSense wall unit to HIGH (the Zehnder equivalent to a standard wall thermostat). Unlike the bathroom boost switches, which run on a timer (set at the main unit in the basement), when you’re done cooking you have to remember to go back and lower the fan speed, otherwise it just stays on HIGH.

The ComfoSense unit also can display error functions or tell you when filters at the unit need to be cleaned. It also has an AWAY function, meaning you can have minimal fan speed to exchange air while you’re on vacation instead of just unplugging the unit altogether.

boost rocker switch
Boost rocker switch in the bathroom.

The boost switch in a bathroom is set to run for 30 minutes on the highest fan speed. So far, this seems to be plenty of time for it to work properly. Unlike a normal bath fan, which tends to be quite loud, even when the Zehnder is in boost mode it’s still incredibly quiet, so guests need to know they only need to press the switch once — it is indeed working.

For the bathrooms, the boost function has been working really well at removing moisture after showers. Nevertheless, in the winter, when temperatures are below 20° F and we decline to use the boost function after showers (again, hoping to hold onto some of the added humidity), the bathroom humidity levels still quickly drop from the 60’s and 70’s back to the mid-30’s in less than an hour (and this is even when the Zehnder fan speed is set to LOW).

We’ve also been happy with the diffusers, in terms of installing/removing them when necessary, but also in terms of their overall look. Whether on more neutral colored walls, or something bolder, they just look nice in our opinion.

supply diffuser
Zehnder supply diffuser on a neutral background on the wall.

They’re subtle enough to blend in to the background, but attractive enough so when they are noticed they don’t stand out in a negative way.

Zehnder exhaust diffuser
Utility room with a Zehnder exhaust diffuser on a neutral background — around the corner from the clothes dryer.
diffuser w: bold colors in bg
Zehnder supply diffuser on a much bolder background.

As far as changing filters at the unit, or even cleaning the core itself, so far it’s been a trouble-free experience.

Here’s a photo of a supply-side filter after one month of exposure in winter:

zehnder supply filter
A Zehnder supply-side filter (MERV 13) after 1 month in winter.

During the summer, of course, they look much worse after a month with so much more “stuff” floating around (e.g. pollen, debris from landscaping, insects, etc.). Also unsurprisingly, the exhaust-side filter always takes much longer to get dirty as stale air makes its way out of the structure (it probably helps that we don’t have any cats or dogs).

And since we didn’t need the framed-out HVAC chase in the corner of our Master Bath for all the ComfoTubes that we initially planned to send up into our ceilings, we ended up using this area for some much needed niche shelving for various toiletries and even some towels.

Overall, then, we’ve been extremely happy with our Zehnder ERV unit.

Windows, Doors, and Suntuitive (Air Sealing #8)

0

Window Options For a Passive House

Even in 2017, when the majority of our build was completed, the number of Passive House quality window and door options was increasing. Today, in 2018, they’ve only continued to grow.

On a side note, the following info would also be appropriate for many Pretty Good House builds.

For example, here is an article from the Green Building Advisor website from June, 2018 discussing high-performance window options: What Windows Should I Buy?

In addition, 475 High Performance Building Supply is selling an Austrian high-performance window, Bewiso:

A New Jersey Passive House builder, Darren Macri, has created his own product line: Wythe Windows

And GO Logic is an importer of a German brand: Kneer Sud Fenstern und Turen

They have an old blog post on their site discussing their history with the brand: GO Logic

Some additional options include:

GLO windows out of Montana: https://glowindows.com/window-style/tilt-and-turn-windows/

EcoSupply Architectural Products: https://www.ecosupplycenter.com/solutions/exterior-solutions/windows-and-doors/windows/

Mavrik: https://www.mavrik.build/materials-1

Zola, in particular their uPVC options: https://www.zolawindows.com/upvc#Slide1

European Architectural Supply (Schüco brand): https://www.eas-usa.com/

Alpen Windows

Klearwall (Munster Joinery, based in Ireland)

Bieber: https://bieberusa.com/why-us/12-reasons/

There are also some custom, small-scale, American-made options as well:

Hammer and Hand

HH Windows

And it’s worth doing an internet search looking for suppliers in your specific area. In our case, Hawkeye Windows and Doors is fairly close, located in Iowa. As I relate towards the end of this blog post, Larry, the owner, really helped me out of a jam when the salesperson for our windows and doors proved incompetent and, frankly, useless. In fact, when a reader of this blog contacted me recently (2020), I had this to say about Larry: “He proved incredibly helpful and responsive. If I was building again, or building for someone else, I would definitely get a quote from him. The real value in working with someone like Larry is that he’s close enough geographically to be willing to travel and do the install with his crew (Midwest region)… in addition to being readily available should any issues develop after installation.”

They all share similar characteristics, including insulated triple pane glass, thermally broken sashes and frames, multi-point locking systems for airtight seals against gaskets on the frames, the European-style tilt-turn function, and the seemingly ubiquitous but beautiful Roto hardware.

It’s nice to see that more options are becoming available to those looking for high-performance windows in the US — hopefully this means a long-term movement towards better overall building standards in terms of quality, durability, and performance.

And here’s a quick overview on high-performance builds and the need for quality windows and doors: Hammer and Hand

Although not everyone is entirely convinced, and there’s still debate regarding exactly what’s “necessary” in terms of performance (the exception would be building to the Passive House standard, either PHIUS or PHI, where the requirements are more black and white). There’s a lot more latitude if building a Pretty Good House, or the homeowner is only looking to meet the benchmark of Net Zero.

Suntuitive Dynamic Glass for Our West-Facing Windows

When my wife’s cousin found out we were trying to build a high-performance new home (a mix of Passive House and Pretty Good House), he suggested we incorporate his company’s self-tinting glass. Used largely in commercial applications since its introduction, the product is beginning to make inroads into the residential market as the cost comes down: Suntuitive

For anyone near the northwest suburbs of Chicago, you can see the glass in person at the Ziegler Maserati dealership in Schaumburg, Illinois: Exterior View

As the product has continued to evolve, they’ve been able to remove much of the “green” look to the glass. This is evident in the Ziegler dealership glass, but even in that application I didn’t think that it was all that prominent. The overall look of the glass was still impressive.

As to function, the Suntuitive coating between the layers of glass adjusts its level of tint based on the temperature of an inner layer. In the summer, this has obvious benefits when high temperatures combine with glaring sun to enter a structure, particularly in the east in the morning or the west in the afternoon (even to the south without some protection with overhangs). But the really nice thing about the product is that it doesn’t tint on the coldest days in winter, allowing for some solar heat gain and natural daylight exactly when you want it most on sunny, wintry days.

For energy reasons, and also personal aesthetic choices, we decided to forego any windows on the east side of our house. Instead, we just have our front door facing the street (it has a limited amount of privacy glass to let in some morning light). On the other hand, because we wanted to use a significant amount of glass on the west side, which faces our backyard, and we knew overhangs couldn’t offer much relief from the summer afternoon sun, Suntuitive was a great solution for us — especially since we wanted to avoid using blinds or curtains as much as possible.

Following Passive House principles for glazing, we wanted to optimize our views and connection to the outside through our limited and strategically placed number of windows.

Here’s a useful video showing the effects the sun can have on a structure in various seasons:

And here’s an interesting video discussing the challenges associated with managing both solar orientation and scenic views when they’re in conflict:

For our house, we only have a single window to the north (for my daughter’s bedroom), while the majority of our windows are on the south side, where we spend most of our time in the living spaces (open kitchen and family room). In effect, we’ve limited our windows in private areas of the house, mainly two bathrooms. Besides energy concerns, we didn’t think it made sense to add additional glass to our north, mainly because our neighbor’s house blocks any meaningful views while also reducing privacy.

Additionally, we have a significant overhang on the south side, which allows us to block out most of the summer sun while allowing in plenty of winter sun for passive solar heating during our coldest months, so the windows on the southern facade easily take care of most of our daylighting needs.

By utilizing the Suntuitive glass on only the west-facing windows (family room and master bedroom) it allows us to maintain our open view of the backyard while avoiding migraine-inducing summer afternoon sun.

Here are the specs for the particular glass we chose to use (they have a wide variety of options, including color variations): Vertical CrystalGray Triple Glaze Performance Sheet – Lee-Whetzel

Although we lose some potential solar heat gain through these windows in winter (compared to the glass in a typical Passive House certified window), we feel it’s more than compensated for by the blocking of hot, bright summer afternoon sun.

Here’s a company video describing the Suntuitive product in real world applications:

Unilux Windows and Doors

My wife’s cousin suggested a couple of options for the Suntuitive glass: Kolbe Windows or Unilux Windows.

We went to see the Kolbe windows in a local showroom, but they didn’t seem impressive. It also didn’t help that the salesperson was dismissive of the product, suggesting that if we were considering Kolbe we should just use Marvin instead (another brand they sold). The salesperson literally had to wander around looking for a sample unit, eventually finding one buried in a corner. We’re not even sure if what we saw represented the full breadth of the Kolbe product line.

At any rate, since Unilux was willing to work with the Suntuitive glazing, it made it easy to go with them rather than trying to convince another Passive House certified window maker that Suntuitive could be compatible with their product line.

[Note: Suntuitive is constantly adding new manufacturers willing to work with their product, so contact them directly if you have a specific brand you’d like to use on your own project.]

After deciding to go with the Unilux windows and doors, we ended up with the following specs:

[Please note: The numbers below were mostly supplied to me by my Unilux window rep. Following up with a Unilux rep on the East Cost, Scott Gibson, from Green Building Advisor, received different information. If you’re contemplating using Unilux, contact your local rep or the company directly in Germany for written confirmation regarding performance numbers — especially if you’re running data through a program like PHPP.]

Main Floor Windows (excludes west-facing windows with Suntuitive):

  • Interior wood with aluminum-clad exteriors
  • Glass: Unilux Super-Thermo 3
    • Triple pane with a reported R-ll center of glass
      • R-8 for whole window once frames are included
  • U-factor of 0.18
  • SHGC of 0.53

2-Basement Windows:

  • Isostar: interior uPVC with exterior aluminum-clad
  • The same glass as the main floor windows.

Two doors:

  • One for our front entry, and one for our kitchen. They both have the R-11 center of glass glazing, with the kitchen door having a significant amount of privacy glass (it faces south), which is really enjoyable on cold days with the sun shining.

We chose PVC for the basement windows to save some money, but also because we thought the natural wood finish on a basement window might look out of place — we’re painting the concrete foundation walls, and partially drywalling an office area, but otherwise we’re leaving the basement unfinished (it will look finished for our tastes at any rate).

The total cost for the windows and doors was just over $26,000 (including the Suntuitive for the windows facing west), with the two doors representing almost $10,000 of this total.

In regards to the Suntuitive glass, it is currently selling for roughly $31/sq. ft., depending on specific application requirements. You can contact my wife’s cousin, Dan, at his email address if you have technical questions, or if you’d like to get a quote for your own project: leed@pleotint.com

I don’t believe the Unilux windows and doors are technically certified by PHIUS or PHI, but their performance metrics are close to the necessary requirements, so we were comfortable using them, especially since we had no intention of pursuing official Passive House certification anyway.

Window Bucks

After firing our two GC’s in February, 2017, we lost a few weeks as we scrambled to cut ties with them while simultaneously lining up new subcontractors to keep the project moving forward.

Once things were back on track, I was able to begin installing the window and door bucks in preparation for the delivery of the eventual windows and doors.

Using 3/4″ CDX exterior plywood, I installed the bucks so they would extend out far enough to meet up with our eventual two layers of 2″ Rockwool Comfortboard 80 and two layers of furring strips for our ventilated rainscreen (vertical and horizontal since most of our charred cedar siding would be oriented vertically).

Here’s how a similar set-up looked on Hammer and Hand’s Madrona House project:

We decided to go with “innie” windows, so our windows would be placed near the center of our wall assembly to optimize their energy performance. Placing windows near the center of the wall assembly also creates nice shadow lines on the structure throughout the day. Overall, we just really like the way recessed windows look on a house.

Prior to construction, I created a mock wall assembly with a window buck, which proved to be good practice for building the real thing.

mock-wall-assembly-w-sealant-in-sun
Mock-up of the wall assembly put together before construction began.

Mock wall assembly after practicing with the tapes:

mock-wall-assembly-w-tapes
This mock wall assembly gave me the chance to practice applying these tapes before doing it for real on the house.

It’s also worth mentioning that it’s important with these tapes to make sure that once applied you go over them, applying pressure, to ensure the adhesive is properly activated. 475 HPBS always included at least one of their blue Pressfix tools in each box of tape that I ordered. The tool is roughly similar to a bondo spreader.

pro-clima-pressfix.jpg
Pressfix after heavy use.

We were following many of the details in Hammer and Hand’s Madrona House project:

I watched their videos dozens of times, especially this one, trying to make sure I got all of the details right. Their Best Practices Manual was also invaluable as I kept referring to it throughout the duration of the build (an incredible gift to contractors and self-builders alike who are tackling a high-performance build for the first time).

Once each buck was installed, I went around and used HF Sealant to seal all the gaps, seams, and screw holes in the window and door bucks.

BR #2 window buck with HF sealant
First window buck installed.

Here’s a close-up of the same window as the HF sealant is being applied:

close up of BR #2 with HF sealant
HF Sealant at the transition between the Zip sheathing and the window buck.

And here’s a different buck being sealed on the interior surfaces:

lwr rgt int wdw buck w: hf sealant
Using HF sealant to seal seams, imperfections, and screw holes in the plywood window bucks.

Another view of the buck being sealed up with the HF sealant:

int wdw buck w: hf sealant

With the bucks installed, I could then begin applying the various air sealing tapes to all the surfaces of the bucks. I decided to use the Pro Clima line of products, available from 475 HPBS, after ordering them and using them to create my mock wall assembly.

The other option would’ve been to use the Siga brand of air sealing tapes, available from Small Planet Supply, or the black Huber Zip sheathing tape.

Although clearly based on my own personal prejudice rather than scientific evidence, I was reluctant to use the Zip tape, 3M tape, or something similar, mainly because I knew the European brands have a much longer track record of success.

Yet another option would’ve been to use liquid applied membranes (e.g., Prosoco, again Zip, or others), which I’ll address later, when noting the details for sealing up my front door buck area.

Knowing that corners and other areas where elements meet up could be problematic for proper air sealing, as pointed out by Sam Hagerman in this Hammer and Hand video:

I started by addressing some of these areas first. For example, here’s the lower right of a window buck where it meets the Zip sheathing:

lowr rgt buck 1st profil at zip

By building up the corners in this way I was hoping to guarantee complete coverage against air and water infiltration at these tricky points.

lower rgt buck w: profil at zip
Same area with overlapping top layer.

Here’s the top of the buck where it meets up with the Zip sheathing:

profil on buck meeting zip
Corner where the buck meets the Zip protected again with 2 separate overlapping pieces of tape.

The Profil tape, which splits into thirds on the back, makes corners much easier to tackle.

After using the Tescon Vana in the upper inside corner of the buck, I used the Profil tape to address the upper outside corners of the bucks:

int buck w: tvana and 1st profil
Tescon Vana, then Profil for this upper outside corner.

Here’s two views of the second top piece for this area: