Before I get to the telling of what's happening with the new house I must take a moment to thank you all for your weird and wonderful suggestions for the blog's new name. It was really hard to decide what the final name should be. I finally went with a name that would make at least some sense sitting at the top of each post. Some suggestions were very clever but were only relevant for that one post where I asked for help renaming the blog. Some suggestions were just cryptic enough that, I have to admit, I didn't get them. Some were excellent but already taken...such as Casa Costalotta. And all of them I completely appreciated. Thank you for your interest and participation in my little blog. And Doris...thank you for your winning suggestion! (Joe & Flora, one of your suggestions I used in the opening sentence...it was a contender). I have added the "passive" edit mark to the new header sketch a bit prematurely I suppose. Same goes for the past tense "built" but we are definitely on target to make these pending characteristics a most certain reality. There's no turning back now...there's a big hole in the ground at Turtle Falls and we no longer have a house, of any kind, to live in at the moment! We must forge on!!
Now, back to what's going on with the house.
Several weeks back we had a meeting with the HVAC supplier for Casa Tortuga, Encore Geothermal Inc. Ras and I have never been known as very conventional, so what we have decided on for our mechanical system is also not conventional, at least not for a passive house. Let me explain.
Passive houses, typically, are primarily heated using the solar gain from the triple-glazed windows strategically sized and placed on the south side of the house. The amount of insulation and the air-sealing is critical for keeping the warm air inside the house in winter and outside the house in summer. The required HRV or ERV helps to condition and distribute the air. A secondary heat source typically only needs to be small, such as a mini-split heat pump or a small amount of electric heat to name only two options. The idea is that by not having to buy a conventional furnace you can put that money into the extra insulation, air sealing and windows. The temperatures in a passive house are supposed to be fairly consistent and slow to fluctuate. Much has been written about whether the criteria developed for passive house for the European market are right for the North American market. The Canadian climate offers up a bit more severity for us to deal with when trying to reach the numbers necessary for passive house certification.
Passive House is in its infancy in North America. Builders of passive houses here, more often than they would like, are having to resort to buying European made HRV/ERV systems and windows because they are not available in the numbers or qualities they are in Europe. That is starting to change, but at a snail's pace. Architect Chris has mentioned that at least one of the Canadian window manufacturers he has approached for our project is striving to produce windows that are good enough for passive house certification.
There's all kinds of info about building a passive house here in Canada and the USA. Many builders of passive houses feel compelled to blog about it to get the word out...exactly the reason why I blather on at great length. There's not a lot of info yet about the experience of living in a passive house, particularly in my area of interest - Canada. The little bit of information I have been able to find makes me a bit apprehensive. It seems temperatures within some of these passive houses fluctuate more than the marketing blurbs say is typical. It's hard for me to determine if this is because of the difference in climate, our relative lack of experience in building passive house here in North America, or the fact that the materials and systems we have to choose from are not the quality with which the European passive house is built.
Admissions of cold bedrooms when doors are closed, temperature differentials from room to room, temperature fluctuations wider than expected, and constant tweaking of mini-split and HRV performance to balance out these characteristics make me wonder. I may have mentioned once or twice how I absolutely dislike the cold. One of my other pet peeves is overly obtrusive sound levels of heating and cooling systems. Loud mechanical systems are simply annoying! All that being said, I'm very sure the mini-split option (the most common secondary heat source of choice) for heating and cooling our passive house is not the way to go for us. Electric heat is quiet but not efficient. Electric cooling...not very quiet. Radiant floor heat is too much heat for a passive house for the expense and it's not very helpful at cooling in the summer. These were not the only options we looked at. We looked at them all. Confusing and unsatisfactory options...each and every one!
So off we go to see Encore Geothermal...and the world made sense once again with our introduction to the Cold Climate Heat Pump.
|Oh...the joys of winter in Canada!|
That's why the good people at Ecologix, a Canadian company from Cambridge Ontario, have developed a cold climate heat pump meant for the Canadian climate. These cold climate heat pumps operate efficiently down to a -25°C outdoor temperature. That -25°C is the efficient operating temperature that is guaranteed with these heat pumps and not just the oftentimes exaggerated marketing hype target. You know the hype I mean...I'll use the car industry as an example. This new car uses 6 litres/100kms. But what isn't stated are the conditions needed to get that actual fuel efficiency, like the outdoor temperature needs to be a constant 15°C, you must never exceed the speed of 80km/h, you must never use your brakes or idle at a stop light, and accelerate only as if you are a member of Gas Savers. Ok, I digress and exaggerate just a bit, but my point is these cold climate heat pumps will work at temperatures of -25°C, day after day. Although the literature for these heat pumps states -25°C, word is that at -40°C they still won't freeze up. It's refreshing when a company actually under-promises and over-delivers. My kind of company...Canadian and modest.
|The Ecologix CCHP pulls heat from the outdoor air to heat the home in |
winter and pumps heat to the outside to cool the home in summer.
The CCHP adjusts capacity to meet the immediate need, delivering
only what the home needs without waste.
"furnace" when we are not supposed to need it but it is the best solution we have found to have everything that we want...quiet, efficient and even secondary heat in the winter and cooling in the summer.
This exercise of planning to build a passive house has raised so many questions that seem almost impossible to answer. Much thought and revision, on many levels, has gone into designing this house. Let me back up a little, to explain one of those more esoteric levels.
The house in the city that we just sold was a very interesting and unique little house..."one-of-a-kind" as all the real estate agents described it. Over the years we have done some crazy things to it, like turning it into, essentially, a one bedroom house, removing the closets because they were so small anyway what was the point of keeping them, removing any semblance of a "yard" and replacing the grass with meandering walkways and low-maintenance perennial gardens, over-spending on the renovation we added in 2010...all because we truly thought we would never move from this house so what did it matter that the house was not suitable for anybody else with clothes, children or dogs...and we would be able to amortize the cost of the reno over the rest of our lives. As always, life finds a way to throw you a curve ball when you get too deep into it. And our plans to stay in that crazy little house forever, ultimately, were severely revised.
That is, for the most part, why our house took so long to sell. We had to wait for a similarly unique buyer with enough money to pay for an over-improved, under-sized house but was neither a clothes horse nor responsible for several dependents of either the 2 or 4-legged type...talk about seriously limiting our market! You can only hear potential buyers say, "too small, no closets, no garage" so many times before you want to throw in the towel.
Ras and I agreed not to make the same mistakes with our next house. Therefore, this house is bigger than we want it or need it to be. And although we are choosing this cold climate heat pump, first and foremost, because we want the benefits it offers us, it is also a consideration for the next people that will eventually own this house. We may be all gung-ho about passive house and willing to live with its inherent characteristics but the next people may not. We really don't like thinking of resale when designing this house but the thought of trying to sell another crazy one-of-a-kind house sends shivers down both our spines. This secondary heat source solution will not only completely satisfy us but, with its conventional furnace look, will put the future owners of this house at ease. Hopefully, by the time we are ready to pass this house along, passive house and cold climate heat pumps will be the norm.
In some way, I truly believe that passive house in North America needs to find its own way. What works in Europe may not be the best approach here...just my opinion. We are trying an approach that we believe we can live with comfortably and efficiently into the future. (Edit May 12: It seems I am not the only one with this opinion. This Green Building Advisor article,"Passivehaus Buildings Don't Heat Themselves", was posted four days after I wrote my post. Confirms, for me, our decision to go for the cold climate heat pump).
Now...if only we could get the building permit! We're apparently just waiting for a few engineers' stamps on some documents. Once we have those...we'll be madly off in all directions. Can't wait! Soon we'll be Living La Vida Ohm Free (Thanks for that suggestion, Kaye. It was also a contender).
That's it for now,
For those interested in more info about the Ecologix Cold Climate Heat Pump, see the following:
University of Waterloo researchers change the face of home heating and cooling in Canada
Canadian Federal Government announce $4 million in support from the Clean Energy Fund for cold climate heat pump development