High performance windows installed

Windows are one of the most critical elements of a Passivhaus and any super-insulated energy home. The placement of the windows, the type of glazing, the type of coating, and the frames all have an integral role in how much or how little energy your home will use. But what most energy aficionados consider to be the most important is the frame. For us, the only real option was fiberglass. Most regular home install run of the mill vinyl, wood or metal – but these materials are simply highly inferior to fiberglass when it comes to energy performance.

“Fiberglass is created by pulling strands of glass through a heated die, resulting in a material that is strong, resilient, and suited to all weather conditions… Energy efficient frames have low conductivity that discourages the transfer of heat or cold into a building. Fiberglass has a much lower conductivity than metal options; simply placing a hand on a fiberglass frame compared to an aluminum frame in -20°C weather makes the difference very clear… Fiberglass is much less conducive to allowing cold temperatures to pass through the frame, thus helping to prevent condensation and loss of heat… Subjected to temperature extremes, windows must remain stable, with minimal expansion and contraction to keep an excellent seal. Considering that the bulk of a window is glass, what better material to surround it with than glass? Hence “Glass on Glass Advantage”. Composed of about 60% glass, fiberglass, like plate glass, has a very low rate of expansion and contraction. Fiberglass maintains an excellent seal with reduced movement relative to the plate glass. Superior stability also results in greater longevity, fewer seal failures, and better paint adhesion.” -Duxton windows

Although we are targeting Passivhaus performance levels for our house, actually purchasing “Passivhaus Certified” windows was simply far too cost prohibitive (~$90/sq.ft.) and must be shipped across the ocean from Germany (that is a big carbon footprint to overcome). There is one Passivhaus manufacturer of windows in Canada that I’m aware of called Northwin, but we didn’t pursue a quote from them, the only reason being is that no one around here had any experience with them, and from what I was told the cost was extreme. I had wanted a recommendation or at least a review from someone who had worked with, lived with or installed them before.

One of our friends had built a very energy efficient house and installed Fibertec windows out of Ontario. Although they were beautiful looking windows, they had nothing but problems with them (air leaking, condensation). My thought is that these windows, made in a warmer part of the country, were not designed with a cold prairie climate in mind (I have no evidence to prove this, mind you). As such we avoided any manufacturers outside of our climate zone. That basically let us with two fiberglass window manufacturers: Duxton windows and Accurate Dorwin, both from Winnipeg MB.

We knew people who’d either installed or worked with these windows before and each of them were happy with them. We received quotes from each of them and they were essentially equal (Duxton being $500 more). We ran the two windows through the energy modelling software and Duxton came out the winner. I’d also talked to a Passivhaus engineer who’d found that Duxton “performed very well in the PHPP.” My wife also liked the name “Duxton” better.

They are a pretty impressive and innovative company. We actually met the owner, Al Dueck, and had a drink with him at a Building Green conference a few weeks ago. The company has recently developed a quintuple paned window! Five panes with a rating of R20! Outrageous.

We ordered the windows way back in early May, before the ground had even been broke on the foundation. I’d been expecting this to be more than an ample amount of time for them to be fabricated and delivered. Well, I was wrong. So very wrong. Although I was told that they would be ready in 6 weeks, they weren’t actually delivered and installed for nearly 10 weeks. Fortunately for us, our builder and the subcontractors were willing to continue on and not wait.

We had everything coordinated when they confirmed at last that the windows and doors had been sent out. Our builder, received the shipment, unloaded them and said “WTF!” We were missing all of the doors and one of the largest windows. It was the end of the day and we scrambled to try and find out which of the three shipping companies may have lost them… but all of them confirmed, when I called them frantically, that they had received the same items. It wasn’t until the next day that we received a sheepish email from Duxton that they had “forgotten” to ship them. Oops!? What a headache.

Not only were we trying to coordinate the shipping, delivery, installation of the frames and smaller windows, but also the “site glazing” (6 of the windows were too large and heavy to be sent as a single piece, therefore the glass and frame were sent separately and had to be installed by another subcontractors). Basically there was a lot of pieces that had to fall into place. And none of them did. But after hours on the phone rescheduling everything, like most (kind of) things, in the end it worked out. The windows and doors arrived and were installed. And they look super sexy.

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Frames only. Waiting for site glazing.
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The triple pane pieces of glass. These made me so nervous. I did not want to be around when they were installed.
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Almost all installed. Note – no door and no window on the far end.

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Basement concrete slab

I do love concrete. It is one of those rare man-made products that border on being a living thing, like plaster or linen.  Those things that have such a rich texture and variation of composition that they seem to beckon you to touch them and get up close for a better look.

Of course, not everyone will share my appreciation of concrete, traditionalists have tended to cover up the concrete or at least extensively treat it with stains and dyes making them more palatable to themselves. Not us. When I told an interior designer about our exposed basement concrete walls, his response was, “Now that’s modernism with a capital ‘M’!” Cool, I said, “What’s modernism with a little ‘m’?” To which, he sheepishly did not have a response (I’m an ass).

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After the walls cured for 28 days, we had to seal the concrete. We wanted to get this done before the slab went in because if we waited to do the floors and walls at the same time, not only would there be framing and drywall in the way, then we ran the risk of the drywallers slopping crap all over the walls and making a mess of our beautiful concrete finish.  Like an idiot, I decided not to purchase a $25 dollar wand sprayer to apply the sealant and instead decided to use a nap roller. A job that would have taken me 30 minutes ended up being closer to 5 hours rolling every inch of the wall on multiple passes (lesson learned).

Next, we had to lift the giant water tank and Japanese soaker tub off of the floor and strap them to the steel beams (getting the tub in the basement was another adventure in and of itself. I will write about that someday). The under slab insulation was then cut and laid. We elected to use 7.5″ of under slab insulation, which is likely overkill, however this brings the floor insulation to R30 (our last house had no insulation in the basement at all). This EPS insulation was pretty cool. Having a honeycomb pattern as the top layer allowed for incredibly easy installation of the PEX piping for in-floor hydronic heating.

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Notice the levitating water tank and soaker tub

We knew we wanted the concrete floors to be a simple natural grey concrete, power troweled and sealed to complement the exposed concrete walls. No fancy finishing, dying, staining or grinding.

Now being that the basement concrete slab was to be our finished floor, it was pretty important to me that it not look like crap. Therefore the quality of the contractor needed to be top notch. Unfortunately for us, that was not how we entered into this venture.

I did not meet the contractor before he was actually on site prepping to pour. My wife had driven home early that day and came upon a most peculiar sight. A rather criminal-looking fellow standing beside a broken down early 1990s sedan, holding booster cables. Our place is a bit out of the way, so this was not a sight one would expect. Of course she stopped to see what the problem was (as the next passerby would probably not be until much later on). He proceeded to tell her that he needed a boost, he’d gotten in a fight with his boss and left from “that house being built down there”, pointing in the direction of our house. My wife, boosted his junk car, and asked if he was going back to work? Nope, he said, and drove off.

My wife drove to the site and found a lone guy working in the basement – no truck, no car, no nothing. She told him she might have just met his worker on the road and asked how he was getting home. Of course, he had no idea. She called our general contractor to come pick him up, however as she was leaving the property his buddy had returned with the car.

When I stopped by later to check on the whole situation, they were still there.  “Working late, boys?” I asked. “Yup,” the boss said, “but we gotta get home, we’re losing light and we don’t have any headlights.” (He wasn’t joking).

He told me that they were planning to have the concrete poured in two days, but would need to finish laying the rebar and tying everything in beforehand. “I’ll be back at 6am tomorrow,” he said, before driving off headlight-less into the night. I came by the house at 7:30am and, not surprisingly, they were not there. Sometime throughout the day however, they were back working away in the basement – this time, they’d brought a rusted old Honda, apparently this one had headlights and was more reliable.

On the Thursday, which was the day of the scheduled pour, they did not show up at all (what other profession could you simply not show up to work and there be no repercussions?). The bossman called our general contractor later in the day, apologizing and saying that he had to fire the criminal looking guy, but promised to complete the pour the next day. I told the contractor that it was tomorrow, or else he was off of the job.

On Friday, I received a phone call from them telling us it was “too hot” to pour the basement slab. Granted it was 34° Celsius. He said that the concrete would cure too fast and they would not be able to guarantee a nice finish. I wondered to myself – is this a convenient excuse for them in case the floors didn’t turn out? What am I to do? Ask them to pour it anyways? I called a couple of friends that I have in the concrete business and asked if they were pouring today. They were. I asked if there would be any reason to not pour a basement today and they told me that an insulated basement would be perfect in this weather – being at least 10 degrees cooler in there and not in direct sunlight.

That afternoon, we made calls to find a replacement for this retard concrete guy. I couldn’t handle it anymore – how many chances do you give someone? That being said we needed the floor done immediately. This idiot had already setback three other trades with his 5 day delay. Especially when Taylor and Curtis worked to hard to be ahead of schedule despite some of the challenges they faced with the Nudura One set up.

Incredibly we talked to Tyco Concrete Finishing, who said they would be able to squeeze us in early the next week. That Sunday evening we met the owner on site (I was relieved to see him drive up in new super duty 4×4 truck). He spent a couple hours with us going through everything, including checking what little work the other guy had done, making sure he knew how we wanted it finished, and confirming all of the dimensions and depths.

Two days later this was happening:

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They had a crew of six guys on site and they did an awesome job. That night we came home to this.

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Double Stud “Deep Wall” Framing

The day following the completion of the excavation, backfill, grading and dirt hauling, Taylor and Curtis with EcoSmart got to work framing the double-stud exterior walls. We had chosen to use the “deep wall system” originally developed by Rob Dumont, a local Saskatoon engineer who is widely recognized as one of the pioneers of super-insulated green building. He has been a major inspiration to the owner of EcoSmart Developments, Murray Guy.

Rob Dumont had been one of primary engineers in creating the Saskatchewan Conservation House – which is one of the original homes that inspired the German Passivhaus movement. This is a fantastic article about Rob Dumont’s own home that he built in 1992 using his deep wall system (it was considered to be the most energy efficient house in the world at the time!).

Saskatchewan Conservation House, 1977
Rob Dumont’s personal home

Rob Dumont developed this super-insulated wall system and Peter Amerongen from Edmonton AB has been perfecting it over the past few years, using it in the Riverdale NetZero and the Mill Creek NetZero homes, amongst others. To my knowledge, no one since Rob Dumont himself, has built another home in Saskatchewan using this type of wall system. I’ve written about this wall system previously, but now we were going to see it come to life before our eyes.

Taylor and Curtis had of course never built this type of wall before, but they had done extensive research and were very motivated about it. This wall system utilizes two 2×4 walls, spaced 16″ apart thereby creating an 8″ void between each 2×4 wall. There is no need to offset the studs as the large void, which will be filled with dense-packed cellulose (recycled newspaper), has no thermal bridging whatsoever. We elected to space the 2x4s at 16″ centers for both the interior and exterior walls. It is possible to space the non-loading bearing wall at 24″ centers, but when attaching the wood siding to the exterior wall (our non-load bearing wall) this might be a little more tricky.

Of course this wall system takes a bit longer to construct then your typical stick-framed house, as each wall needs to be built twice. What the guys did was to lay the lumber one on top of the other to ensure that the spacing was appropriate. The studs were nailed together with a double bottom plate (we will be pouring 1.5″ of concrete for the main floor so you another bottom plate was needed in order to secure the drywall to it) and a double top plate. The two walls were then secured to a 16″ wide 3/8″ OSB header and footer and tipped up into place using wall jacks. The walls were then glued and nailed into place and sheathed on the outside.

The first day they framed the west wall which is 30′ in length. Honestly, the excitement of seeing a wall could not be contained that day.DSC_0316

Side door with transom overtop
Side door with transom overtop

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Day two they framed the north side which is a longer 48′ wall with minimal penetrations – one window in bedroom, one in the hall for ventilation and the back door.

Day three was the west wall, again 30′, which included three large windows (energy efficient geeks will note that there is minimal benefit to large windows on east side and there is risk of overheating in the Spring and Fall) however these windows look onto an amazing river view that we had to enjoy. The windows will be glazed in a special coating to reduce heat gain (more on that later).

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Looking east to the river
View from the kitchen sink
View from the kitchen sink

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Main entrance and foyer corner window
Main entrance and foyer corner window (tricky detail)

Day four they ambitiously completed our southern wall, our primary 48′ wall, with three MASSIVE windows – all of which are more then 10′ wide – and a patio door to the deck. This side of the house looks onto a beautiful southern view across the river valley, but also will be a source of heat gains in the wintertime.

Four walls!
Four walls!
HUGE south windows
HUGE south windows
Dining room corner window
Dining room corner window
Framing details
Framing details
Corner window framing details
Corner window framing details

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Next would come the interior walls and roof – and suddenly this was looking like a house!

Water Tank and Foundation Finishing

DSC_0472We finally decided at 1pm on Monday that we were going to do the water tank in the mechanical room. We had went and viewed our neighbours set-up and talked to him about his experience. It all seemed good enough. But meanwhile that morning, the crane had shown up and lowered the giant steel beams into the walls of the foundation.

I had watched the crane go to work in awe like a little kid – “Woah, a crane!” It was pretty awesome to see the crane towering over our trees and lowering the steel beam into the grooves that Taylor and Curtis had left when pouring the concrete a couple days earlier.

It was an impressive sight to see.  The slid in so effortlessly.

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Within a few hours, the guys were hanging the joists and starting to the lay the floor. You’ll notice that the beams and all of joists are within the envelope of the foundation walls. This was intentional from an energy efficiency point of view. There is no thermal bridging at all with this system. Oftentimes typical houses are built with the joists sitting on top of the concrete wall or on a ledger of the wall. Both of these are a bit more work then simply using hangers. And the former, requires excessive use of spray foam to seal.

The way we did it required a taller basement wall, but there is zero chance of air leakage, thermal bridging or heat loss with this.

Anyways, the carpenters were working fast. Crap, Darcie and I realized, we had to decide immediately whether or not we were going to have the water tank in the basement. The carpenters were going to be done the floor system the next day, which meant that the tank needed to go in the basement NOW.

I made some calls and found a manufacturer east of Saskatoon who sold large tanks. We hopped in the truck and  made the 45 minute drive. We had debated briefly about what size of tank to get – essentially everyone we talked to told us to purchase the largest tank that would fit in the house. That meant we could get a 2100 US gallon tank – measuring 88″x88″. If you can’t picture that, well, it’s big.

We drove back to the land and within a couple hours were ready to haul the giant beast of a tank into the basement…

Only problem was the crane was long gone, and there was a huge gorge – 11′ deep and 6′ wide – all around the perimeter of the house. The four of us put our heads together. We all agreed this would have been a LOT better to have done when the crane was here… Crap.

The options were slim. The only possible way was to jimmy up a rickety makeshift bridge between the foundation and the ground using 2x10s and some left over joists. We decided to push the tank off of the trailer (there was no way to carry it) and roll it to the side of the gorge. From there we wrapped two large ratchet straps around the top of the tank and lashed them to the back of my tractor.

Now came the dangerous part – Taylor and Curtis pushed the tank onto the shoddily crafted bridge (one false step would mean certain death or at least dismemberment) while I slowly backed up the tractor thereby keeping tension on the straps and allowing the guys to ease the tank across the “Bridge of No Return.” My wife cringed as she watched the bridge bow under the weight of the tank and guys.

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Miraculously no one was killed. Not even a little bit.

Once we had the tank to the edge (Taylor had also built a small ramp on the inside of the foundation), I could simply back the tractor up and lower it down.

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That went well.

By the end of the day, the guys had the floor framed – pretty impressive. They’d poured the basement on Friday and floor was framed and sheeted by Wednesday. Time for a dance party.

We all grabbed a beer to celebrate and as we were standing there, an eagle flew by carrying a fish.  We were all in awe and Curtis said “and this is where you guys live?”!  It was awesome.

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PS. One more geek/nerd energy efficiency thing: They wrapped the house in the water proofing seal, but also wrapped it up and around the plywood to create a complete seal around the entire basement. It is possible that a small amount of air leakage could occur through the plywood and the top of the joists and foundation wall. This simple trick tightens the house up even more.

Concrete wall reveal

The day following the pouring of the concrete, we were ready to pull off the plywood forms and see what lay beneath. Leaving the plywood on for more than a day would cause them to adhere too firmly to the concrete and make them extremely difficult to remove. We were a bit nervous. We had been pegging a lot on how these walls would turn out – they would be, after all, our finished interior walls, so I really hoped they wouldn’t look like crap.

First we had to remove all of the exterior bracing that the builders had spent four days installing, tweaking, levelling, and straightening.

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They had done a great job. The walls were perfectly straight and square.

We started unscrewing the plywood forms and Cha-Ching!

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They looked frickin’ awesome!

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As we removed the forms, I had to chuckle, because the builders, who had for the previous week been cursing the Nudura One system, as they saw the finished look decided the would “use it again.” I guess looks due make up for a bad personality from time to time.

We spent about two hours removing all of the forms. As we got towards the base of the floor, we crossed our fingers hoping that it had all settled nicely to the bottom without any “honey combing” of the concrete that would need to be parged. Impressively, it looked excellent all the way from top to bottom.

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Dang, those are sexy walls.

Foundation/Basement Forming

Meanwhile, the foundation work continued to move forward. A few weeks ago I’d written about the Nudura One Series of ICF. We were quite excited about it for a number of reasons. Firstly, basements are generally BORING. So, with using this system of ICF we could have a finished interior wall of concrete immediately, which would look aesthetically pleasing and be something of interest and uniqueness in the basement. No need for any extra framing and drywall. Second, in terms of energy efficiency, this system should perform better than conventional ICF. You are not insulating the walls of the basement from the house itself (standard ICF and standard poured basements have insulation on the inside and cannot use the thermal mass of the basement walls). Being that we have a huge thermal mass in the walls (and floor) of the basement, they can store a lot of heat to radiate to the rest of the house either through sunlight or simply from the in-floor hydronic heat. Essentially functioning like a giant battery.

About a week prior the forms had been sent out. There was an incredible amount of insulation that was stacked in the shop.

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And the day following our stresses with the septic system, Taylor and Curtis got to work building the basement forms. They had budgeted about four days to get the forms up and one day to pour. ICF goes fast, they said.

… But not this ICF. This basement was a massive pain in the ass. After one day, the guys only had one row of the seven done. There was no simple way to attach the forms and keep them locked in place. You see, in standard ICF, the blocks are basically like Lego. There are little grooves on the inside and outside that line up and attach to the corresponding little plugs on the other block. Snap snap snap, it goes together. Easy.

Typical ICF

This was not easy. The little Lego grooves and plugs were only on the outside of the blocks. Not the inside,  as the plywood slabs simply butted together creating big seams and gaps (wouldn’t tongue and groove plywood have made sense, Nudura!?). Frustrated at the lack of progress, Taylor called the Nudura sales rep who came out to the site. Amazingly, he had never seen the Nudura One series before. Like never ever. As they all worked together to try and troubleshoot this problem, they eventually decided to call the head office in Ontario, Canada and their technical support team.

IMG_2544They suggested make 2×4″ L-brackets to support and anchor the forms (uh, that’s part of the plan?). Oh and as for the gaps in the plywood? (Where concrete would completely burst from when pouring.) Well, just use Tuck Tape, they said. Tuck tape!?? (I suppose it’s slightly more classy then duct taping the forms). Jeez Louise.

Unfortunately, after building a bunch of the 2×4″ L-brackets and bolting them onto the forms, the carpenters realized that this was not going to work at all. These brackets did nothing and if anything made the problem worse by pulling the forms further inwards, causing even greater warping of the walls. Thanks for the “technical support”!

(You’d think they’d never sold this product before – which, later we found out they have never actually used it in a residential application!)

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Over the following four days, Taylor and Curtis grudgingly put the forms together and stacked them higher and higher, eventually reaching the top at 10’6″. They put an absolute tonne (perhaps 2 tonnes) of rebar in the ICF both vertically and horizontally to reinforce the high walls and provide the structural support for the beams, joists, and double wall that would sit upon it. Seeing the forms go up was pretty exciting, but just don’t look too closely or right down the line of the wall…

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Because that ain’t straight.

I have to admit, I was more than a bit worried. How the hell were they going to straighten these walls? I wondered.

Taylor and Curtis had also eaten through their projected timeline and still had to try to straighten the walls. After four days the walls were not even stacked, let alone straight and ready for concrete. Over another three days, all they did was straighten and adjust the walls. Using large bracing and strapping to make them level, straight and even. When Taylor finally told me they would be pouring concrete the next day, I had to run over and make sure.

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Praise Jebus! (This whole process is making me become very religious it seems.)

The following day the pumper truck was out, pumping a buttload of concrete into the basement walls. Now was the real test of the untested Nudura One walls and the Macgyver skills of the build team.

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I was nervous that day at work, just waiting for the phone call from Taylor explaining that there had been a catastrophic failure when the walls of the forms burst under the pressure of the concrete causing the walls to break apart and concrete to fill our basement.

But that call didn’t come. Relieved, we drove home at the end of the day. The walls were still standing and they were filled to the brim with concrete!

The next day we would pull the plywood off and see what magic laid beneath.

PS. Nudura has offered to cover at least some of the extra time of the build team for Research and Development of the Nudura One series.

High Performance Windows

One of the things I am most excited about in our house are the windows. We have a lot of windows in the house, 25 to be exact. And they are not terribly small. Even before knowing anything about energy efficient building, I’d always loved homes with large expansive windows overlooking a beautiful view. However, when building an extremely energy efficient home, the placement, size, glazing, window to floor ratio, and type of window matter a lot.

First, and perhaps most important, is which direction your windows should face. Obviously in the northern hemisphere, the sun is in the south. Therefore, the majority of your windows should face south and be able to take in the sunlight through the winter months when the sun is lower in the sky to provide some passive heating. Conveniently the sun is higher in the sky in the summer, so as long as you have properly sized overhangs or shading in the summer then you can prevent overheating. Recently we were in a neighbour’s house that was not designed with energy efficiency in mind. They have large south windows that are completely exposed, as well as some larger east and west facing. Even though they would (theoretically) have a great view, they had the interior blinds drawn on almost all of the windows!  Interior blinds and shades do very little to prevent overheating as the light/heat has already entered the space and will simply heat the blinds and radiate inside anyway.

For us, we maximized our southern exposure (but not too much as you can still overheat in the winter – even at minus 40° Celsius). And minimized our northern, eastern and western windows. Fortunately for us our best view is to the south and east. We do have a couple large windows on the east side of the house to take advantage of the river valley and our unobstructed view of the sunrise (to not put windows there would be foolish). We would have liked to have put more windows on the east, but in order to do so that would require shutters on the exterior, thus obstructing the view anyway. Shutters are really the only way to “shade” light from the east and west as the sun is too low in the sky throughout the year (at sunrise and sunset) to actually “shade” it. As for the north we don’t have much of a view, and so only have two windows. One in a bedroom for ventilation and fire safety and the other in the hall for ventilation. Northern windows really don’t provide any benefit in energy efficiency and are actually an energy penalty.

As for glazings, these are really amazing and can help with heat gain or blocking unwanted heat.The glazing does not at all block the view. I think of it like sunscreen. On the east and west windows, you want more sunscreen because you don’t want to overheat. On the south you want minimal sunscreen because you want that good passive heating in the winter (as long as you account for passive shading in the summer).

Ok so what type of windows do you buy? Wood, PVC or fiberglass? We had really hoped that we would be able to afford fiberglass windows. These are simply the best for energy efficiency, durability and quality. The frames themselves are made of 60% glass (fiber-glass) and so they move with the expansion and contraction from the heat and cold of the windows. Consider -40°Celsius outside and +20°Celsius inside. That is a 60° change that occurs through about a one inch space. PVC and wood will flex and bend at a different rate then the glass, leading to more air leakage, reduced air seal, and eventual failure of the window over time. Fiberglass however does not have the same issues. Duxton Windows has some excellent information on their website.

Duxton fiberglass windows

Now that we had an idea of what we wanted, we needed to determine which supplier to go with. We priced out Duxton (fiberglass), Accurate Dorwin (fiberglass) and Plygem (PVC/wood). We did not consider any of the crazy German imported windows. Shockingly, people actually do this (this is where the economics of Passive House and extreme energy efficiency clash with reality and sustainability, as I’ve written about before). I was actually talking to a house designer the other day who was raving about some German windows they’d started to import. Indeed they are impressive windows – but they are coming from fricking Germany! My thought when building a “sustainable” home is that we should be really considering if we are spending our money wisely or if it could have a better effect elsewhere (for example, spending $15,000 more on windows to get a marginal energy improvement versus $15,000 in solar panels). AND if you are importing your high performance windows from 4000 miles away and shipping them on a cargo ship across the ocean… well… is that sustainable?!

Anyways, I knew that the fiberglass windows would be more expensive than wood/PVC – but how much more was the question? When we received the quotes back I was pleased to see that the fiberglass windows came in only 20% more expensive then PVC. For the added efficiency, durability, warranty and, not to mention the larger viewing area of the window (fiberglass is stronger therefore can have a smaller frame and more glass) it was a no-brainer to go with fiberglass. We ended up choosing Duxton over Accurate Dorwin due simply to the fact that our designer had recommended them. The price difference between the two companies was marginal.

Via duxtonwindows.com

In designing the house and choosing the windows I tend to think about what Christopher Alexander of the Pattern Language says: “light on two sides of every room.” I loved reading this book because it was all about aesthetics. Written in the 1960s, it did not give a crap about energy efficiency. It was a nice reality check against all of the energy efficient dogma that in some cases can really get out of control. You still need a home that you actually want to spend time in.

Pattern Language by Christopher Alexander

Final planning

We have spent the past 9 months exhaustively planning this house and finally the light at the end of the tunnel is almost here. The design is done, the quotes have been tendered and received, the design fees have been paid (almost), the development permit approved, and we are just waiting on the appraisal from the bank and stamped drawings from the engineer. Initially the planning process was fun, but about three months ago we had pretty much had enough of it.And now, well, we have definitely had enough of it.

I keep thinking to myself “haven’t we talked about this house long enough??” But there are so many important little details that go into the planning and building of a house. I may have had a small idea of this before, but really this whole process shines a completely different light on the importance of Planning. When moving into and renovating an old house, you learn to live with and work with the idiosyncrasies and nuances of an old house (nothing being level, that weird door, baseboards not quite lining up, that one awkward window that looks onto nothing, and so on), but when building a house, you really don’t want to start off with any of those weird things. I am very detail oriented and like to research things to the n-th degree, much the chagrin of my wife from time to time – except in this process. My anal-retentiveness has finally come in handy!

If you are planning to build a house, and are not detail oriented then you need to learn to be one. Otherwise you are liable to get a home that may be close to what you had asked for but not entirely what you had expected. I cannot tell you how many little mishaps, potential mistake, errors and omissions we have already caught and corrected. It is crazy to me at times, but really there are so many aspects that even the people you are paying to know about all of it may miss some of these details or do it the way they always have done it (even if you specifically say you want something else). So it’s all on you. You’re the only one there to make sure that it is done how you actually want it. Which means you have to research and know enough to at least ask the questions that will lead to ensuring that you will get what you want.

I have learned now to tell our team that when we want something, I ask to confirm that it was done, and then follow-up to make sure. I’m certain that the various people working on the house will be completely sick of me pestering them by the end, but I don’t care. I want to make sure that our house turns out as we have intended it to.

And if there is something that I don’t know about then I ask someone who does know to check it. And then double-check it and then triple-check it. Incredibly, on triple-checks we have still caught errors.

In the end, all of this stuff is just on paper. We actually haven’t even done anything yet. So we will see what the actual build process goes like. I’m hoping (wishful thinking perhaps) that because of the significant focus on the details in the planning stages that maybe, just maybe, the build process will go smooth. But this hope is not going to allow me to assume anything. At all. Ever. IMG_2699

Final house design

Well, after twelve revisions and eight months of planning, designing, redesigning, changing, scrapping, planning, and redesigning some more we’ve finalized the house design at last. It’s funny, we had been so sure of what we wanted and didn’t want before, but gradually this all changed. I’m super happy with the design. And although it is different in some ways from our original plan (i.e. basement, open kitchen/living/dining room), it is more true to our original vision then we had ever expected: a quaint, simple, modern farmhouse. It’s crazy to think about how far our design gradually strayed from this original vision before we finally were guided back towards the root of what we wanted.

In a lot of ways designing the house has been a full circle – as we meandered away from our vision, only to come back to it. It was also an evolution. The final product was far better than what we had ever originally envisioned. So I suppose you must go through the process. You are never going to get what you want the first time through, despite how confident we felt that we knew exactly what we wanted. We didn’t. We needed to explore. We needed to think about all kinds of scenarios and possibilities before finally discovering what it is that we really want.

And so, here it is. I cannot wait to see this become a reality.

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Choosing a super-insulated wall system

After deciding on the mechanical system of the house we needed to choose what type of wall system we were going to use. As I’ve learned, for an Eco-house, there’s more than one way to skin a cat! (who came up with that saying?!) Again, it was a matter of weighing the advantages of each and ensuring that our contractor felt comfortable with whatever system we decided on.

Passivhaus tends to utilize a double-wall system, although there is no set way to do this, as long as you meet the Passivhaus criteria.

Examples of Passivhaus wall systems.

This method is nothing new, there are many houses from the 1970s that utilized a system of a 2×6 wall at 16″ on centre (o/c) and offset with a 2×4 wall 16″ o/c for an interior wall. Nonetheless, biggest concerns in ensuring an exceptional envelope of a Passivhaus or any other super-insulated home is: thermal bridging and airtightness (and to a lesser degree the overall R-value).

Thermal bridging is basically an easy pathway for heat to flow out of your home. In a conventional single 2×6 wall, this happens every 16″ as the 2×6 piece of wood is connecting the inside to the outside with out a “thermal break”.  This is why a R19 insulation in a 2×6 house actually has a lot less R-value.

Airtightness is how leaky is your house? While thermal bridging can be limited by proper construction design. Airtightness can really only be ensured while on-site building the house. Airtightness is tested with a blower door test and is rated based on “air changes per hour a 50 pascals of pressure.” As previously mentioned, Passivhaus standard is 0.6 ACH. The Canadian R2000 is 1.5 ACH.

 R-value is of course also important, but less so than reducing thermal bridging and ensuring excellent airtightness. This is because R-value is a rating of the “effectiveness of insulating materials.” You could have an R50 house, but if it is leaky and has thermal bridging it will not function like a “true” R50 house.

In the last 10 years, there have been numerous high-performance, high-tech wall systems that have been developed such as Insulated Concrete Forms (ICF – concrete poured into thick pieces of foam) and Structured Insulated Panels (SIPs – OSB laminated to the inside and outside of a big piece of foam), both of which eliminate thermal bridging altogether by not utilizing timber at all.

ICF
SIPs

Passivhaus’ use a variety of options, though many that I’ve read about use some form  of double-walled systems often with SIPs on the outside and 2×4 timber framing on the inside. An 8″ thick SIPs panel is about R33 on it’s own so add that to the R11 of a 2×4 wall and you get a well-insulated house with minimal thermal bridging.

We had already decided that we would be best served, given our rural location and 55km distance from town, to pay our contractor to be at the site working – instead of driving back and forth with lumber. As such, we wanted to utilize a company that could provide either a prefabricated wall systems (which could be erected very quickly on site) or a “kit” (all of the wood cut to size to be put together like a model). Because we have a large shop on site, the materials can be all shipped at once and stored inside. Also, this significantly reduces onsite waste and chance of error.

One of the companies we looked at was Pacific Homes out of Victoria BC, who our builder has worked with on previous projects. This company produces a “Smart Wall” system – a prefabricated timber wall that eliminates thermal bridging and significantly increases R-value. A standard 2×6 wall is R19. The 2×6 Smart Wall is R31.

We compiled a list of “attributes” for each option that we felt were most important in our decision-making process:

– R-value

– Airtightness

– Ease of construction

– Construction labour time

– Material waste

– Total cost (time/money/energy)

Options for walls were as follows:

1.  Pacific Homes 2×6 Smart Wall with 4″ of rigid foam (EPS) on the outside. 

This option was appealing due to it’s low cost and simplicity. However that simplicity quickly got tossed as we are quite certain that we want to use cedar siding on the house. Trying to secure cedar siding to foam is not possible without significant strapping and labour to ensure everything is kept in place. This would work for stucco, but it would not be ideal for us. R-value of about R45. Airtightness might be less than other options given that this is really a single-wall system.

2. Pacific Homes 2×6 Smart Wall with offset 2×4 standard wall at 16″ o/c.

This is a simple option as well. The outer wall would be prefabricated  and shipped. Given the prefabrication, the house could be framed with roof, windows and doors installed in 2 weeks (same as option #1). The internal framing could be done after and standard cellulose batts used inside. The good thing about this over the first is that the plumbing and electrical would not pass through the 2×6 outer wall therefore eliminating potential air leakage. The cost of this one was quoted at about $5000 more than option #1 due to the extra 2x4s and insulation batts. R-value for this was R41.

3. 14″ thick ICF

ICF uses styrofoam forms with concrete poured into it. It’s appealing for a few reasons: no thermal bridging, super strong walls (disaster protection), has a good R-value (R48) and is naturally airtight (expect in the corners and around openings which of course need to be sealed like any other system). It’s a bit controversial though and quite a bit more costly in terms of time, money and energy. It is a labour intensive project and we simply did not think it would be worth it in our case.

4. 8″ SIPs with 2×4 standard wall at 24″ o/c

SIPs are touted as an energy conscientious option that can be installed extremely quickly. A 2000 sq.ft house can be erected in two days. SIPs uses two sheets of OSB laminated to a slab of EPS foam. It is very strong and does not require further framing. The R-value of an 8″ wall is R33 so combined with a 2×4 wall at 24″ o/c you get R44. I thought this would be a pretty excellent option. SIPs are only marginally more expensive then a standard wall system (and when you factor in the reduced labour cost, it is negligible) and are quite a bit less than ICF. Unfortunately, SIPs have been found to have some pretty serious problems with moisture build-up, airtightness problems, and early decay. None of those sounded good to me. Sorry SIPs, not for us.

5. 16″ Deep Wall System

One of the engineers on our team had worked with a group from Edmonton AB who utilized a “Deep Wall System.” I had never heard about this, but was intrigued.

Deep Wall System – Mill Creek Net Zero House, Edmonton AB

Essentially this uses a 2×4 wall 16″ o/c on the outside and 2×4 wall 24″ o/c on the inside. A 3/8″ thick piece of OSB is cut 16″ inch wide for the header and footer. The 2x4s are spaced and secured to the headers and footers with a 3/8″ OSB sheet on the outer wall. Essentially you make a box with a mesh on the inside. The 16″ cavity is filled with blown in high density cellulose. This gives an incredible R-value of R56! As if that’s not impressive enough, the material cost of building is about the same as a standard 2×6 wall (not including cost of extra labour time for framing mind you). The airtightness on the Riverdale NetZero house was 0.59 ACH and the Mill Creek NetZero house was 0.36 ACH. Amazing. As I later found out, the energy guru and one of the creators of the Saskatchewan Conservation House  (the house that inspired Wolfgang Feist and led to the German Passivhaus Institut), Rob Dumont, developed and used this exact method on his house in Saskatoon SK.  He built his house in 1992 and at the time was considered to be the most well-insulated house in the world (the airtightness was also an incredible 0.47 ACH). Why didn’t they just tell us that in the first place!? There would have been no decision-making necessary. We would have just done what he did.  We will still have a company cut all of the lumber to size and ship as a package. Although this system will take a bit more time to complete (due to framing labour) the advantages of this wall system for us far exceeded the other options.

I’m super excited for our super-insulated and locally developed wall system.

-K