superinsulated house – Blue Heron EcoHaus

Once you go black…

Posted on September 1, 2016 by kent

We’d really hummed and hawed about what to do about the basement parging for most the winder and early spring. Although our plan had been to do the house all black initially.

HouseRenderHeader

But last year we’d hesitated. And I’m not entirely sure why. We couldn’t run the wood siding all the way to the ground, like the rendering shows, because of the 8” of foam on the exterior basement walls without some seriously extensive strapping. Alas we had the stucco guys parge the basement foundation and then leave it while we contemplated our options: leave it or go all black.

While taking photos for the post about the concrete retaining wall, Darcie, my wife, said, “The house doesn’t look right. It looks like it’s floating. It’s weird.” She proceeded to spend the next several days playing with Photoshop, filling the gray parging with black and analyzing it from multiple angles. After a week of scrutinizing the Photoshopped images, she said, “Look. We should do this.” Pointing to an all black house.

If there’s one thing I’ve learned is that once my wife has made up her mind, it’s best not to disagree. It is only futile afterall. “Yes honey,” I replied (these two words are the most important for a husband to know, by the way).

So I called the stucco guys and asked them to come back. It ended up taking a number of weeks for them to finally show up (typical). But only a couple hours for them to transform the house.

I gotta say, I don’t know why I’d hesitated, because once your go black… well, you know the rest.

Musings on Passive House Standards and the Costs of New Home Construction, Part 3

Posted on April 2, 2016April 2, 2016 by kent

If you have not yet read my posts (rants) in Part 1 and Part 2, maybe check those out first.

Have you heard of the Pareto Rule before? It’s more commonly known as the 80/20 Rule. It says that for many events, roughly 80% of the effects come from 20% of the causes.

I think that Passive House (PH) follows this rule to a T. It has certainly been our experience in building an extremely energy efficient home and following the principles of PH. I believe that 80% of the benefits of PH come from about 20% of the cost and effort (from Part 1 of these posts, I noted that our financial cost was about 8% more than a standard house construction). Whereas to get that last 20% to the hit the PH certified requirements, you’re going to have to spend 80% more… At least this was my assumption.

Still being the curious person I am and because I kept getting asked about it… I just had to know. How close does our house come to the PH standard?

The only way to find out would be to either track the house over the next year or to have someone run the house through the Passive House Planning Package software (PHPP) to predict our values.

As you may recall, we were never pursing PH certification, right from the beginning we were told the cost-effectiveness (80/20 rule) was just not there. Maybe if there was some incentive or rebate for going full-out, one could justify it. We were also told that there was no need to use the PHPP as it was too expensive. This latter statement however is simply not correct.

I decided to ask around and see who could put our house through the PHPP for us. Or at least get a price quote for it. Maybe it would be too costly and so I wouldn’t bother if it was. After a few emails, I was eventually referred to a very well-respected PH consultant out of Alberta – Stuart Fix at ReNu Building Science. I sent my email explaining that we’d already built the house and so really can’t change anything now, but due to curiosity I was wondering if he could run the house through the software. No problem he said. The price we were given was entirely reasonable and was actually less than what we had paid to run the house through the inferior HOT2000 software prior to building. Crap!

After a couple weeks we received the results, not surprisingly: we weren’t a Passive House. But the results on the various aspects of the house were very interesting and lead to some interesting points of discussion.

Based the three criteria for PH certification, recall:

Space Heat Demand: max. 15 kWh/m2a OR Heating load max. 10 W/m2
Pressurization Test Result @ 50 Pa: max. 0.6 ACH
Total Primary Energy Demand: max. 120 kWh/m2a

Our results were as follows:

Space Heat Demand: 37 kWh/m2a
Heating load: 22 kWh/m2a
Pressurization test result (assumed 0.6 ACH, prior to testing)
Total Primary Energy Demand: 116 kWh/m2a

So, you can see that the only criteria we met was the Total Primary Energy Demand. The blower door test we did later came back at 0.72 ACH (we’d run the software assuming 0.6 ACH as a target). As a result of the actual pressurization value, this would correspondingly increase the other values, but, for argument’s sake, let’s simply say that the Total Primary Energy Demand we either met, or were very close to meeting, while for the Heat Demand and Heat Load, we were WAY above the German PH maximum values.

I won’t reiterate why this makes sense given the climatic and heating requirement differences of the Canadian prairies versus Germany (see Part 2). But I had to ask the PH consultant:

“If we were still in the planning stages of the house, what would be your recommendations to try and reduce these two values (Space heating demand and heating load)? Not that we would change anything at this point, but I’d be curious as to how we would have gotten those values lower – and if it would have been at all possible with our type of house and in our climate to feasibly meet the PH requirements as stated?”

The ways to reduce the heating load & demand are as follows:

More insulation (you already have great R-values)

Lower airtightness (dropping from 0.6 to 0.3 has quite an impact, but you’re already doing tremendously well)

Add more south glazing, reduce all other glazing. (You already have a great balance of glazing)

Build a larger home (!?!?… small homes are the hardest to make meet an intensity based target, as they have the largest surface area to volume ratio. Meaning that a larger building squeezes more floor area into slightly more exterior envelope area, reducing heat loss per unit of floor area. The Germans do this to motivate one to build multi-family dwellings… but the result in North America has been a lot of larger single family homes getting certified).

Your home is a great example of why you don’t see certified Passive House buildings taking off in Canada. It’s damn near impossible to design a compliant home, without either blowing the bank or ending up with a solar oven. I’ve designed many compliant buildings, and 99% of them end up backing off on insulation and glazing to be around where your home is. You’ll note that local Net Zero Energy homes have similar envelope performance to your home; it’s most cost effective from that baseline to invest in solar PV generation than to add more insulation.

Under the section of the report on Energy Balance Heating, I asked, “I was surprised by the amount of heat loss through the walls as well as the windows – is that due to the size/number of south windows? Or does that relate to the number of windows on the east/west and north sides more so? How could we have changed that to reduce the heat loss?”

Ideally, if the insulation in all areas of the building cost the same, you’d want to balance the R-values so that the heat loss intensity rate is the same through all envelope elements. Your exterior above grade wall has the highest relative rate of heat loss, so that’d be the place to add more insulation first if you want to improve performance. If you want to optimize R-value ratios this way, it’s smartest to add in the cost/ft2 of each insulation type, then you can maximise your return on investment. For example, adding 1″ of cellulose in the attic is much cheaper than an inch of foam outside of a wall.

The glazing of course has the highest rate of heat loss, but that’s just because you max out at around R10, where your opaque assemblies are R50+.

Your North, East, and West windows are NET losers of heat, while the South windows offer a net gain. This is as expected, and is really the basis of Passive Solar design, that a South window can actually HEAT a building throughout the heating season, with the right recipe. If you wanted to optimize the glazing further, you can add more South glazing while removing glazing on the other elevations (North being the biggest drag on efficiency), which will continually reduce the annual heating demand (how much energy is consumed to heat). This is a Red Flag area though, following this path of more South glazing will eventually cause overheating throughout the year. Prediction of overheating / discomfort is an area where the PHPP is very poor, and I’ve been burned in the past on some projects where we pushed the Passive solar too far in an attempt to reach certification. I now use IES<VE> as a energy modelling tool because of its ability to accurately predict overheating.

“Did you have any thoughts or considerations you would have given us had we run these numbers off the bat with the house planning? “

I’d honestly say you’ve done a great job on your home. It’s pretty much impossible to meet the PHI Passive House criteria for a small single family home in Saskatchewan, without significant and typically unjustifiably cost. The PHIUS criteria is based on a more climate-specific analysis, which attempts to stop investment in conservation at the point a little bit beyond where renewable generation is more feasible. Meaning it’s more realistic to meet the PHIUS+ targets, though we’re not seeing much uptake in the Prairies.

All of this was very interesting and at the same time reassuring to me. Like many others, I had put a lot of credence on the PH standards as the be all and end all (even still despite reading and appreciating the issues I’ve previously discussed). It was good to hear that the assumptions we’d made were in the end in line with the reality of trying to build a PH in Saskatchewan.

Even still there was one last thing that I just had to know… it kept coming up again and again. It was one of those pesky assumptions we kept getting asked about. And one of my recently reposted blogs on Green Building Advisor brought it back to my mind again… German windows.

It is regarded that the German (or Polish and Lithuanian) Passive House certified windows are the creme de la creme of windows. They are attractive, heavy, thick (6″ wide!), and expensive. But if you want to reach Passive House standards, you gotta have ’em! (Or at least that’s what they say).

I felt a little bit guilty asking for quotes on windows that we were never going to buy, but my curiosity just couldn’t be helped. I wanted to know how expensive PH-certified windows would have been for our place. We’d heard outrageous prices of up to $80,000 for some homes.

We tendered a couple of quotes and received a reply from Optiwin of Lithuania. The salesperson was exceptionally thorough and I was really impressed with his communication (which made me feel more guilty). After a couple of weeks I received the pricing back. I was actually surprised that the cost of the PH windows was only $17,000 CDN more than the windows we purchased from Duxton Windows. Although they would have been certainly way outside our budget anyway – they weren’t 400% more than the price we paid by any means (just a measly 75% more). Nonetheless, I really had to pause again and wonder, why? What would make these windows $17,000 better than the fibreglass, triple pane windows we got? The U-factors and solar heat gain coefficients were not that big a difference. Maybe the the locking mechanisms of the windows could get you a bit lower on your airtightness – but $17,000? How long would it take you to save on heating bills to justify that “investment”?

All this being said, I’m happy to have answered my lingering questions and to confirm some of my assumptions. The bottomline, of course, though is that you want to be able to sit back and be happy with what is around you. To know that you did the best you could in building a sustainable home for the future.

I can’t complain.

Musings on Passive House Standards and the Costs of New Home Construction, Part 2

Posted on March 17, 2016 by kent

If you have not read Part 1 yet, please go back and read it first.

In mid-November of 2015, just prior to us moving into the house, we were asked to be apart of the Passive House Days tour (a world-wide weekend of awareness of Passive House and energy efficient building). Well, not “officially” – we were asked to be apart of the tour by the event organizer in Saskatchewan who is the Passive House (PH) consultant on what should become the first certified PH in the Saskatchewan. Even though we did not build a PH, we did follow their standards as closely as I could justify, but from the beginning we were not pursuing certification.

Although all of the visitors on the PH Days Tour were very interested in our house, our process, and why we did the things we did, one question we got a lot was, “If you were following the PH standards why not go all the way for certification?”

First, let’s back-up a little bit. Indeed the principles of a PH are second to none. From Passipedia: “Passivhaus is a building standard that is truly energy efficient, comfortable and affordable at the same time.” So simple. Brilliant even. I wanted to build a PH. Who wouldn’t?

Strangely, if you visit Canadian Passive House Institute (CanPHI) website there are total of 5 projects that have received Canadian PH certification. If you look up the PH Project Database there are a grand total of 23 houses in all of Canada that have received certification.

Why the discrepancy you may ask? Why so few certified projects?

This is a bit complicated and took me awhile to figure out. But here are the basics as I understand it: the Passivhaus standards were developed in Germany for German buildings in the German climate (obviously). However, when other builders in other countries tried to build a “Passivhaus” in say the USA, England, or Canada, they realized something profound: Hey… wait a second… I don’t live in Germany!

Maybe trying to build to German PH certified standards in Minnesota or Saskatchewan is going to be really difficult? Maybe impossible? Or maybe possible but really expensive? Or maybe possible but a really uncomfortable building to actually live in?

Still PH institute satellites started to spring up in most countries around the world. Slowly, Passive Houses, built to the German requirements, started to be built in other countries with the first certified Canadian building being built in 2009. The uptake, however, was certainly not rapid nor widespread. Why? Was it not as the PH Institute of Germany said that these buildings are “truly energy efficient, comfortable and affordable”? Or is it just that we are too cheap and/or lazy and/or complacent to meet those strict German requirements elsewhere?

It seems like this is something that these PH satellites were struggling with as discussed here, here and here.

A few years ago though, some people started to say, this is silly – why are we following German standards and requirements for our buildings when we don’t actually live in Germany?

The German PH standards are as follows:

Space Heat Demand: max. 15 kWh/m2a OR Heating load max. 10 W/m2
Pressurization Test Result @ 50 Pa: max. 0.6 ACH
Total Primary Energy Demand: max. 120 kWh/m2a

Simple enough right? Hit these numbers using the PH planning software and your building can be certified as a PH. Where’s the problem?

The Pressurization Test for 0.6 ACH is strict, but not impossible. There had been many houses built to this level of airtightness before PH came around. Rob Dumont’s own home in Saskatoon in 1992 tested at an awe-inspiring 0.47 ACH.

Jumping to the third requirement, the Total Primary Energy Demand of 120 kWh/m2a ensures essentially that you are not wasting energy or are at least using it wisely. It forces you to use energy efficient lighting, appliances and mechanical systems. I don’t think anyone can argue with that as being important to green building.

The real problem though, in my opinion, is the Space Heating Demand of 15 kWh/m2a or heat load of 10 W/m2. These numbers dictate the maximum space heating allowed for each square meter of a building. Remember – this is based on a German climate.

In Germany the number of heating degree days (HDD) is around 3100 compared to over 10,000 HDD in Saskatoon. So that means there is over three times as much heating requirement in Saskatoon as compared to Germany. Besides that, who really cares what your heating demand is? With the maximum energy demand of 120 kWh/m2a already stated, what difference does it make whether you use 50% of that to heat your house or 10% in terms of your overall efficiency? This is my real beef with PH and the one that most others working towards PH in countries that have climates other than a German one tend to struggle with too.

Recently the PH Institute in the USA (PHIUS) split off (or was banished – depending on what you read) from it’s affiliation with the German PHI. This allowed them to develop their own standards and specific requirements for climate zones in the USA (Minneapolis also has different heating needs compared to Miami) and also to use North American calculation values instead of European. As a result it is now ~~easier~~ – ok, let’s say, attainable – to hit the PH targets for your Minneapolis house using a Minneapolis climate to calculate your requirements. Now that makes sense to me.

Sadly, the Canadian PH Institute has been resistant to following their American counterparts and has continued to align itself with the German requirements. Thus making it darn near practically impossible to meet the PH standard and become certified by the Canadian PH Institute.

There is a small loop-hole of sorts though, a Canadian house can pursue certification via the PHIUS, which is somewhat closer to our climate in the northern States. Although the conversion is not exact, the Space Heating Demand requirement for the northern USA is about 30 kWh/m2a (or double that of the German standard maximum). That’s better, but still the maximum heating degree days in Saskatoon are more than any other place in continental USA. Nonetheless, there have been a few of PHs in Canada that have used the US system to become certified (ok, like maybe 10 or 12).

I told you this was complicated…

Anyway, let’s try to bring this full circle, back to my original question of why don’t we just build all new houses in Canada to the PH standard?

I hope that I have presented the argument that it may not be realistic to build a certified PH in Canada and follow the original edicts of the German Passivhaus Institute of “energy efficient, comfortable and affordable.”

From Part 1 of this post, you may be able to see that there is a HUGE chasm between how most new homes in Canada are currently built as a result of our pathetic building code allowing inefficient homes to perpetuate, and the extremely difficult PH standards currently set in Canada.

Unfortunately, I think the CanPHI has done itself a disservice in not distancing itself from the German PH Institute. By not developing it’s own Canadian climate specific standards for the unique climate zones of our country, which maybe (just maybe) one day could be adopted on a large nation-wide scale.

Until such a time that the CanPHI recognizes this and modifies their requirements appropriately and regionally, I doubt that PH will ever gain much more than a very small handful of faithful followers willing to spend, at all costs, to meet an arbitrary set of values developed on the other side of the world.

That being said, I do KNOW that you CAN in fact build a house in Canada that IS energy efficient, comfortable and affordable.

But it isn’t a Passive House.

Because that’s what we’ve done.

house-snow

Musings on Passive House Standards and the Costs of New Home Construction, Part 1

Posted on February 24, 2016March 5, 2016 by kent

A friend of mine sent me this article for Tree Hugger yesterday about an Irish county that made the Passive House standard for all new home construction. This is a pretty big deal. The question then came up – why doesn’t Canada (or the USA) adopt such strict and stringent standards to their new home construction? Certainly the Paris Climate Conference of 2015 has finally made it official what everyone and their dog already knew: the world is overheating and we need to do something about it before we all die. Building better homes could make a massive difference in our world’s energy use. It is well-known that a certified Passive House uses 80-90% less energy than a standard house.

The problem, as usual though, in making such rigorous standards mandatory is a combination of bureaucracy, status quo, and resistance to change. In this post and my next, I will make the argument that I believe there is a skewed perspective on both sides of this battle in Canada.

Did you know that the minimum standard for wall construction in Saskatchewan (a province that has frigid winters of -40° temperatures for long stretches and over 10,000 heating degree days per year) is a 2×6 wall with batt insulation? The effective R-value of this wall is only R17.5 due to thermal bridging (as the wood studs bridge between the inside and outside of the wall). This standard must be out of date, you say? In fact, this was recently upgraded to this absurdly pathetic level in 2012 (it was only a 2×4 wall before that). Shameful.

As if this wasn’t bad enough, most homes in Saskatchewan feature R12 in basement walls and only R40 in the attic. There is no requirement for insulation under the slab of the house. Also, the building code requires only double-pane windows – such insufficient windows account for a massive amount of heat loss of up to 50% (these are usually vinyl framed windows, though sometimes wood or aluminum). And placement of these crappy windows can lead to further issues with heat loss due to inadequate southern exposure and large windows on the north side of house. Furthermore, air leakage rates in most new homes is about 2.0 ACH@50pascals (which is actually one of the lowest values tested in Canada). (Source: Energy Standards by Ken Cooper)

I assume that you can get the picture that our homes are generally very inefficient (don’t think that this is specific to Saskatchewan – this is relatively consistent across North America).

Although we did not build a Passive House, we followed the principles of this as closely as we could financially justify (which is the rub, more on this in my next post). For a quick comparison, our house has R56 walls, R80 attic, R32 basement walls and under-slab. Our latest air tightness test was 0.72 ACH@50pascals (and with some extra tightening we’re hoping to get this to 0.65 or less at the next test). We used triple-pane fibreglass windows. The design of the house maximized heat gain through the south windows and minimized heat loss through the windows on the east, west and north sides. Passive shading with our roof overhangs prevents overheating in the summer. The positioning of the house is directly south (a luxury we have living on an acreage). We also installed PV panels to offset our meagre energy use, which are becoming more and more affordable.

Now, a lot of people wonder and ask (I know I did prior to building), that it must cost substantially more money to build a house to this level of efficiency?

The simple truth is that it does not have to.

The general consensus is that a new custom home in Canada, excluding the cost of purchasing land, is between $200 and $300 per square foot to build (a contractor spec “cookie cutter” home built to the minimum standard with minimal features and cheap finishing can be $175/sq.ft or less). Indeed this is large range – for a 1500sq.ft home you could either spend $300,000 or $450,000. But for argument’s sake, let’s say $250/sq.ft is a realistic cost of a new custom home (we will also assume that most people would not build to the bare minimum construction standard of a spec house and see the benefit of adding triple pane windows and a 2″ layer of EPS foam on the outside of their 2×6 wall).

OK so where are the extra costs?

I would say that the design planning and orientation of the house will be the single biggest factor in determining your initial and long-term costs in a high performance, energy efficient house. It does not cost anymore to build a house with your windows facing north instead of facing south. Positioning the long side of your house to east does not cost anymore than facing it south. Designing correct overhangs for shading does not cost anymore than designing insufficient overhangs. Designing outcroppings, bay windows, and cantilevers does not cost anymore to design than a rectangle or a square-shaped building. Placing operable windows appropriately for cross-ventilation does not cost anything extra either. But all of these decisions and factors can have huge ramifications on the cost of construction and/or long-term costs of operation. We had several team meetings during our design process (including a Passive House certified designer, contractor, and LEED engineers) to decide on which systems would be best suited to be optimally energy efficient, be comfortable to live in, and also to make sure everyone, including sub-contractors were on the same page. This extra consulting time accounted for 2.5% of our overall cost.

In terms of actual construction costs, we built a double 2×4 stud wall that is 16″ wide. The cost of materials for this wall system versus the cost of 2x6s and the 2″ of EPS foam is almost negligible. Framing labour costs were slightly more though as each exterior wall was built twice (accounting for an additional 2% of the overall budget). Remember though our design is simple, a rectangle, meaning four walls – no bays or outcroppings. We also invested 20% more in purchasing fibreglass framed triple-pane windows versus the usual vinyl or wood triple-pane windows (accounting for an additional 1.75% of the overall budget). Insulation costs slightly more but pays for itself in short order when compared to long-term operation costs (the upfront cost is an additional 2% of the overall budget). Airtightness of the house did not cost us anymore than the standard vapour barrier (although it does require some attention to detail by the tradespeople) with the exception that we needed to install a heat-recovery ventilator which cost $1200 (0.3% of the budget).

But there are also some possible cost savings to consider. One can get away with a smaller mechanical heating system due to the lower heat load required in a super-insulated and airtight house. For us, our mechanical system cost about the same as a standard house due to us deciding to install in-floor heating and a wood burning stove. Although you certainly could get away with baseboard heaters or a very small forced air furnace combined with a heat coil on your HRV if you so chose (for us we wanted the in-floor heat and a wood stove – you can read about our reasons for this here and here). Most new houses also have air conditioners installed. We do not (cross-ventilation, insulation and proper shading is all that is needed).

The bottom line is that it cost us about 8% more to build a house that is in the range of 75-80% more efficient then a standard new custom home.

After these extra costs are accounted for the rest of construction costs are basically the same as any other house – how much do you want to spend to finish the house is based on your taste and how much you want to invest in your bathroom fixtures, lighting, hardwood flooring, custom cabinets (vs. Ikea), appliances and so on. Also, how much sweat equity do you want to do yourself? All of this will have a big impact on your end costs (consider, painting our house took 5 full days, but saved us about $6,000+. Installing the tile in the bathrooms and kitchen ourselves took 10+ full days, but saved us another $8,000).

Ok, so you’re probably thinking, how much did this damn house actually cost you? Tell me already! Although I haven’t done our final-final tally yet, it is in the range of $280/sq.ft. But this also includes the cost of our 6.2 kW solar PV system, our septic system, and the cost of trades to travel the 30 minutes to our house each day. Removing these factors, to build the same house in an urban area, you could easily do it for $250/sq.ft.

Say… that’s pretty much the same as what we said a typical new house would cost, right?

So why the heck isn’t everyone doing this??

Well, it goes back to the fact that there is an unfounded assumption that building an energy efficient house costs a lot more (I think we’ve shown that it simply does not have to). It also does not help that energy costs from non-renewables such as coal-fired electricity and natural gas are very cheap still (even so, those extra 8% in building costs for us should be paid back in less than 12 years in monthly energy bill savings). And the public outcry for action is not yet greater than the apathy of maintaining the status quo on the part of our government, the building industry, and those contractors who have been making a tidy profit on their suburban sprawl spec houses.

Part two to come…

Observations, expectations, and regrets

Posted on February 20, 2016February 20, 2016 by kent

As I’ve written about building our house over the past 18 months or so, I’ve commented several times that the decisions we were making in energy performance and efficiency of the house were all theoretical. Certainly, we based our decisions and assumptions on solid foundations of research, well-established protocols, software design and modelling, and the recommendations of others who have built high performance buildings or through websites and blogs of others. But STILL. I couldn’t be sure how the house would actually function. How efficient would it be? Would we overheat? How much solar power would be generate? What are our power bills going to be? How comfortable will we be? Oh and of course, do we have any regrets? These were all questions on move-in day that we had yet to answer.

Here are some observations from the first three months of living in the house.

We have had an unseasonably mild winter this year including several days of above freezing temperatures in January and February, which generally are our coldest months of the years. In fact, the past 5 days have been between +1°C (34°F) and +6°C (43°F). Normally the ice from the river is not breaking up until mid- to late March, but just yesterday it’s already opened up (#globalwarming).

But even so, we have had a few of our more typical extremely cold days too (we couldn’t get off this easy of course). In December we had a couple days of -40°C (-40°F) or colder. One of these days was a bright and sunny Saturday, the news here reported that it was the highest day of power usage across the province for the year. Our dogs were lying in the sun panting and the temperature on the thermostat read 24°C (76°F) – without the boiler running – purely from passive solar heating. I had to laugh. We even had to crack a window for awhile so we didn’t overheat.

warmday

Even though that day was great to see how well things performed under extreme conditions (very cold day + lots of sun = no active heating required. Awesome) I was a bit worried that we might overheat on milder winter days with lots of sun. But, for whatever reason, this really hasn’t been the case. Within a few days of that extreme cold snap, we were back above freezing temperatures with lots of sunlight. I think a couple days it did creep up to +26°C (+78°F) on the thermostat due to passive heating, but with our well-planned operable window placements, we could simply open a window or two and cool things down if needed. It seems bizarre to me that I’d need to open a window in the middle of winter, but it really does not bother me to do it. But it also makes me very happy (and relieved) that we really thought out well how to get good cross-breeze ventilation throughout the house (although we thought this would be for summer passive cooling not the winter too!). If we didn’t have this I might be cursing myself due to overheating issues.

All this being said, of course, on cold and cloudy days, the boiler and in-floor heat runs. We have it set to keep the indoor temperature at 20°C (70°F). We played around a bit with what setting to keep it at – going as high as 72°F (comfortable all the time, but easier to overheat with passive heating, also running the wood stove would make it too warm) and as low as 68°F (too cold in the morning, even with a sweater on, and needed to be running the wood stove morning and evening). We both wear a sweater in the house in the morning – cheaper to put a sweater on then to pay for more power. If it is really cold out then I light a fire in the wood burning stove, which is a nice luxury to have. When we tried setting a lower temperature in the house, I was needing to light a fire every morning, which was a hassle and not something I was overly motivated to do every day.

I’ve started tracking our solar generation through our 6.2 KW ground mount PV system with the plan to monitor this for the year. This time of year makes for the least amount of solar generation due to the short days, more cloud cover, lower height of the sun in the sky, and SNOW. I’d not really considered it before but snow and ice covering the PV panels is crazy frustrating. I guess I assumed the snow would just fall of it. Not so. The first couple of times this happened I shouted out in horror – we had a bright sunny day, but due to a snowfall in the nighttime our panels were 100% covered! I grabbed a ladder climbing up to clean the panels with a broom – an arduous task with the wind blowing and -20°C (-4°F) temperatures. There must be a solution to this I thought, but after reading several websites, it seems like the only solution is a long broom handle or to wait for the sun to melt it off. This was so aggravating – seeing our energy generation oppurtunities being squandered. Aside from a 16′ long broom handle, I’ve not yet found a good solution to this problem (and perhaps there is no solution).

I’ve also started tracking our energy use, but this has been more difficult as we have an outdoor chicken coop with a heat lamp and a water heater that is on 24/7. These suck energy like crazy. I’m sure these three chickens are costing us a fortune right now (they better start laying golden eggs) – in fact, I think heating their little 24sq.ft coop is more expensive then heating our 1240sq.ft. house. So for this year we will see what the total energy use. But for next year, we have a second transformer located next at our shop (and not connected to the PV panels), so I will try to run the chicken coop power from there, which will give us a more accurate reading of the house’s energy use for 2017. (I also need to build a passive house chicken coop now).

I guess the last thing that everyone seems to ask – which is interesting as it is one of the first things they ask after, “So you’re all settled into the house?” … “Any regrets?” or “Anything you would change?” To be perfectly honest, my answer is, “No. Nothing.”

We really love the house. We love the design. We love the style. We love it’s performance. We love the comfort.

We spent a lot of time planning, designing, and researching the house. We did not compromise and we followed the adage to: “Do it right the first time.”

I have no regrets.

Airtightness: Blower Door Testing

Posted on January 23, 2016August 15, 2018 by kent

Excellent levels of airtightness are equally, if not more, important to the level of insulation you decide to put into your house. These really are (insulation and airtightness) the two pillars of an passive house and pretty well any other Eco-house building.

For our house, we’d gone with high levels of insulation in the range of 3x the typical amount for standard construction: R32 under-slab and basement walls, R56 walls, and R80 attic. However in deciding our insulation levels and our targeting goals for airtightness, we did try to strike a balance between cost-benefit and recognize the point of diminishing returns.

I have written about our insulation choices previously here and here, so I will not go into that as much, but in terms of airtightness there are some basics that are worth discussing. The fact is: air leaking into and out of a building is not efficient no matter how much insulation you have in the walls. Although insulation decisions, thermal bridging reduction, and solar gain can be designed into the house, airtightness can really only be ensured while actually constructing the building. Airtightness is tested with a blower door test and is rated based on “air changes per hour a 50 pascals of pressure.” Typical construction in Canada reaches about 3 ACH. The Canadian R2000, our high-efficient energy standard, is 1.5 ACH. While the Passive House standard is a whopping 0.6 ACH.

Although I was hoping we could target the extremely difficult goal of 0.6 ACH as per Passive House standard, the question was – how far ($$$) are you willing to go to reach this? As with insulation levels, there is a point of diminishing returns. Will 0.8 ACH versus 0.6 ACH be anymore noticeable in terms of user comfort? And over the lifespan of the building would you ever balance out these costs?

We decided to set an ambitious, but realistic goal, of 0.8 ACH.

The reason for this was four-fold:

1. Our house is not big. It is a rectangular bungalow at 1240 sq.ft. The blower door test is an test of absolute air leakage from the building – not a relative test. By that I mean, that a large house can more easily meet a lower ACH level then a smaller house due to the greater volume of the house overall.
2. We were not prepared to spend the greater amount of money on air sealing tapes, interior sheathing, and the labour to do this. A standard house is sealed with a 6 mil vapour barrier (cost is $50 per 8’x500′ roll) and Tuck Tape ($6 per roll). A Passive House is often sheathed with 5/8″ OSB ($25 per 4’x8′ sheet) on the interior to serve as it’s vapour barrier or high-end Intello Plus vapour barrier ($320 per 64″x164′ roll) with the seams sealed with Tescon Profil/Vana tape ($45 per roll). It does not take much in the way of math skills to see that the latter option can get extremely expensive. But if you really want to ensure you hit that Passive House 0.6 ACH target, that’s probably what you need to do (the Tescon Profil tape is often used on the outside walls as well to seal the air barrier and windows/doors).
3. We were not pursuing Passive House certification, so really there was no point in ensuring we hit 0.6 ACH. If you’re spending the money to have a Passive House consultant work with you at the initial design stage and you’re spending the money on the high-end Passive House certified windows, the special tapes and the extra insulation, you better make sure you hit 0.6 ACH or all of that expense will be for nothing. For us, if we made 0.6 ACH, great, if we didn’t, oh well.
4. We were installing a wood burning stove and chimney. Although the stove itself is very high quality from Morso in Denmark, I figured this extra hole in the wall would likely negatively impact our airtightness. But we were not budging on not having a wood stove. We also had another extra hole in the wall for the water cistern in the basement, but again this could not be avoided.

All that being said, we did make every effort to design the house to be as airtight as we could. The dense-packed cellulose in the walls itself provides a high degree of air sealing on it’s own. We limited the penetrations into and out of the house by selecting a condensing dryer from Bosch and having an electric boiler (the only penetrations are the chimney stack, the water cistern pipe, and the HRV). We used a standard 6 mil poly for the vapour barrier with acoustic sealant at every seam. Each seam was also taped with standard Tuck Tape to ensure another layer of added protection. Around the windows and exterior doors we purchased and used the Teson Profil air sealing tapes to attach the vapour barrier to the frames. Although this tape is very pricy, it made sense to me to use it here as the greatest area of air leakage is often at the window frames and doors.

Now it was time to test the house.

The testing is done through a Blower Door test. “A blower door is a powerful fan that mounts into the frame of an exterior door. The fan pulls air out of the house, lowering the air pressure inside. The higher outside air pressure then flows in through all unsealed cracks and openings.” The test is repeated in the same way by drawing air into the house. “The auditors may use a smoke pencil to detect air leaks. These tests determine the air infiltration rate of a building. Blower doors consist of a frame and flexible panel that fit in a doorway, a variable-speed fan, a pressure gauge to measure the pressure differences inside and outside the home, and an airflow manometer and hoses for measuring airflow.”

Essentially it simulates wind blowing against the house in all directions at the same time. The test takes about an hour to administer with the tester taking multiple readings at different fan speeds both while depressurizing and repressurizing the building.

While the test was running we also used an infrared meter to look at any hot/cold spots.

A couple days later he sent us the results: 0.8 ACH at 50 pascals.

Right bang on our goal. Not bad. The guy who tested it said it was the tightest building he’d ever tested before.

I was happy enough with it, but a couple days later I happened to be standing beside the chimney on a windy day and I could ever so slightly hear a whistle through the pipe. I looked closely at the seams and saw they were not fully sealed. Damn!

We’d also had some crappy construction locks on the doors and I put my hand against them. I could feel wind there too! Double damn!

After sealing these leaks and a few other tiny ones we found, we did another retest a couple weeks ago. This time, the results were 0.72 ACH at 50 pascals. Not too shabby.

After talking to the tester, though, he thought that given the higher than expected discrepancy between the depressurized and repressurized values that maybe the vents of the HRV had opened slightly causing a skew to occur. He’d like to do one more retest in a couple weeks, thinking this would take it down to 0.65 ACH or lower. At this point, he’s doing it at no charge as he’s simply interested to see what the truest level of airtightness is.

For me, I’m happy to know that we reached almost Passive House airtightness values while still being as economical as possible.

*** Please see the UPDATED BLOWER DOOR TEST POST for the redo test final results! ***

High performance windows installed

Posted on August 4, 2015August 4, 2015 by kent

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.

The triple pane pieces of glass. These made me so nervous. I did not want to be around when they were installed.

Almost all installed. Note – no door and no window on the far end.

Basement concrete slab

Posted on July 25, 2015July 25, 2015 by kent

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).

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.

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:

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

Water Tank and Foundation Finishing

Posted on June 21, 2015July 21, 2015 by kent

We 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.

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.

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.

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.

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.

Foundation/Basement Forming

Posted on June 11, 2015June 11, 2015 by kent

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.

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.

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.

They 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!)

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…

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.

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.

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.