Monday, December 6, 2010

Why is this stuff still new?

I was reading an article recently on something called The Advanced House. It's a pilot project by the Natural Resources Canada to build a home that uses all kinds of energy efficient systems, such as passive solar sunrooms, double wall framing, and Integrated Mechanical Systems (essentially a large hot water tank connected to heat exchangers. Any air or water leaving the house has all its heat extracted. The hot water tank then supplies not only the water but also heat via either forced air or radiant hydronics.)

It's pretty cool stuff, and not terribly complex. But here's the thing: this house was built as a demonstration project... in 1991. From all that I've read, many of these systems work well and have payback times of less than a decade. They should be standard procedure in 2010. So why aren't they?

One of the great parts of my job is that I get to interview all kinds of interesting people and pursue stories just because I find them intriguing. A couple of months ago we decided to do a story on passive solar design. We had lined up the experts, got the information on the theory, and all we needed to complete the piece was a local home that incorporated passive solar. We found a few, but they were all straw bale places. For our purposes we really wanted one that wasn't freaky; we wanted to see what passive solar looked like in a normal, ordinary home or cottage.

We finally found one... in Burk's Falls, an hour's drive north of here. I spoke to architects and builders around Muskoka and got the same answer every time: nobody does that here. If you want lots of windows, they said, you put them on the lake side regardless of what direction you're facing. Who cares about getting free heat from the sun?

When we toured the home in Burk's Falls, though, we found that they had a wall of passive solar windows on the south. They also had lots of windows on the north, where the lake is. It's not the ideal as far as passive solar goes, but as the owner said, what are you going to do? Block off the view?

They had all kinds of really cool technology, including an integrated mechanical system that took hot air from the third floor sunroom and ran it through a heat exchanger to heat the water. They had woodstoves, just like any other cottage, but they had water jackets in the chimneys to reduce the amount of heat going up the stack. The walls were double thick construction with blown cellulose insulation, and they had a double layer of drywall on all walls and ceiling which acts as a very effective form of thermal mass. (The designer told me that doubling the drywall had the same effect as they would have got by putting a three inch thick concrete slab on all floors, except that with a concrete slab they would have had to reinforce all the floors.)

The overall effect was to make a 3500 square foot cottage that will stay above freezing all winter with no outside heat at all. Pretty cutting edge, right? Uh-uh: this was built in 1998. Which brings me back to my earlier question: why is this stuff not standard?

I think part of the answer comes from my friend Joe. He's recently finished building his own house and used non-standard framing (double 2 x 4 walls, 24" on centre). He said the 16-inch standard for framing originated with builders using lath and plaster for the walls -- the wood they used for laths in England wouldn't hold the plaster if the studs were spaced more than 16 inches apart. In other words, we're still building walls in 2010 to accommodate technology that was outmoded in 1950.

There's good reason to be conservative when building, to not leap into every new idea that comes along. After all, mistakes have to be lived with for a long time, or can be expensive to fix. (Urea formaldehyde, anyone?) But some technologies are ideas whose time has come.

I'll post a link to the passive home article when we run it, likely in the spring.

(Update: here's the article: It starts on page 24.)

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