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Energy-efficient homes not difficult Contractor shares ideas on thinking ahead
during home construction to keep heating costs lowShawn Giilck Northern News Services Published Thursday, May 23, 2013 The Inuvik contractor has just put the finishing touches on his latest energy-efficient house on Franklin Road. He said there's no reason why other contractors and government departments, especially the NWT Housing Authority, can't use some of his methods – especially given the current energy crisis in Inuvik.
Sharpe provided the Inuvik Drum with a recent energy audit on the home that concluded it has an EnerGuide – the national energy efficiency rating system – rating of 80, which is near the top of the
line for energy efficiency.
Sharpe's previous home at Shell Lake, he said, came in with an 82 value.
Both of those scores hover in the same range as Inuvik's energy-efficient house built as a demonstration by the GNWT, Sharpe said.
He's currently living in the house on Franklin Road, and was delighted to have the chance to show it off.
He said he began with making the house extra-warm and inexpensive to operate with some simple upgrades, to start.
Sharpe started with the walls, by using 2-by-10-inch lumber instead of the standard 2-by-6-inch lumber. He then double insulated the walls, giving them an R40 value. The R ratings are calculations of the transfer of heat through building materials such as windows and insulation.
"You can do that for maybe 25 per cent more cost in the wood," he said. "And then the extra cost of the insulation. There's really no extra cost to labour in doing it. I just insulate the (expletive deleted) out of a house when I build."
He followed that up by using a metal foil called Reflectix instead of a simple plastic vapour barrier. The foil reflects heat back into the house, adding some extra R value to the equation. It's similar to what some clothing manufacturers including Columbia Sportswear are using in winter clothing.
"In the winter time what it's doing is reflecting the heat back into the house," Sharpe said. "It's not going out."
As well, he installed that foil on the outside of the house, with the idea of reflecting the summer light and heat back into the great outdoors, rather that transferring it inside, for some added comfort during the midnight sun days.
"It reflects the sun's heat back, keeping the house cooler."
All the windows in the house are quadruple-paned. A sliding door is triple-paned only because he couldn't find one in a quadruple.
Other ideas were more subtle. He had his workers tape over every staple hole in various materials used inside the walls and ceilings to eliminate as many drafts as possible. The walls were constructed so that installing lighting switches and wiring didn't involve making cutouts in the insulation and vapour barriers.
He built a master bedroom without a window to minimize drafts and keep the blazing summer sun at bay.
Sharpe installed a wood stove in the centre of the house to maximize efficiency. The ductwork in the home pulls some of that air down into the crawlspace to heat it as well.
He has a high-efficiency furnace in the house but said the woodstove works well enough that it's rarely used.
Sharpe installed an air exchange system that circulates air every three hours keeping the house fresh to compensate for its air-tightness. It's a well-known fact that fresh air is easier to heat than stale air.
"I've been in the construction business for the last 40 years," he said. "All the housing authority wants to do is build three- and four-bedroom boxes. They've got no vision or anything.
"I don't use the same construction methods the housing authority does," Sharpe added. "I'm the only one in town building more upscale housing and this kind of energy-efficiency. The housing authority could be using quad-pane or triple-pane windows, and they don't."
He said even something as simple as improving the insulation along the lines of what he's done would be very feasible for the corporation, which owns many of the residential units in town.
Any extra capital and construction costs would be recouped in the energy savings, he said. Considering the cost of synthetic natural gas the town is currently using, that should be a significant benefit to everyone.
Not surprisingly, the NWT Housing Authority had a different perspective on the matter. Larry Jones, the manager of construction services, said the corporation is doing everything reasonable to achieve similar energy efficiency ratings in its units locally.
Even 25 years ago, the housing corporation was building units to the R2000 standard, which is a highly energy-efficient measurement.
"Historically, the housing corporation has always met or exceeded the energy standards of the day. For examples, in the early to mid 1980s, we started to build houses to the R2000 standard, which exceeded the code requirements."
Existing units are being re-insulated as maintenance goes on, Jones said, as well as being switched to triple-pane windows. Other improvements have been made as well, including ventilation systems, low-flow shower-heads and other appliance alterations.
"New units have to meet new standards that came out in 2011 that were incorporated into the national building code," he added. "We're reviewing our current approaches to energy retrofitting and adding to our current standards as needed. But it has to be cost-effective and there has to be some good sense to it."
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