He says builders and home owners spend too much time worrying about the cosmetic appearance of a house, and not enough attention to what is hidden away in walls.
Mr. Braden thinks governments could adapt his construction technique to social housing, and free low-income earners from utility bills. The extra-thick walls and vapour barrier might add $5,000 per unit to the cost of a row house, but he said body heat from residents and waste heat from lights and appliances would be enough to keep the houses warm, without a furnace.
Because he wanted to live without accessing the electricity grid, Mr. Braden did spend $42,000 on his solar panels and wind turbine, an expenditure he confesses "is a little bit over the top," but his high-efficiency house doesn't rely on them.
The efforts to build houses that don't need outside energy are being watched intently by conservation experts, who say they could hold promise. They're at the "demonstration stage now, very definitely, and I think we'd all be fascinated and delighted to see if it could become mainstream," comments Peter Love, the Ontario government's top energy conservation official.
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Anatomy of a green home
House builder David Braden says the home he has built near Hamilton is one of the most energy efficient in Canada. Mr. Braden says its triple-insulated 12-inch-thick walls and unique vapour barrier will allow him to keep his home warm this winter without a furnace.
An overhang shades the west-facing side, keeping the house cool in summer.
Windows on the south-facing side are equal to 6 to 8 per cent of the floor space.
The south-side overhang has been designed to shade the lower windows in summer to prevent overheating while allowing lots of winter light.
A heat-recovery ventilator provides fresh air without wasting energy.
Electricity generated by a wind turbine and solar panels feeds a bank of batteries in the basement. When the batteries are fully charged, excess energy is diverted to a ceramic pad that heats the basement floor.
HOW THE WALLS ARE CONSTRUCTED
Two separate stud walls, three layers of insulation and a vapour barrier outside the innermost stud wall keep the home virtually airtight.
1 Exterior cladding
2 1/4-inch chipboard
3 Housewrap
4 Outer stud wall insulated with R-14 batts
5 5 1/4-inch cavity insulated with R-22 batts
6 1/4-inch chipboard
7 6 mm polyethylene vapour barrier
8 Load-bearing stud wall insulated with R-14 batts
9 Electrical boxes and plumbing lie within the vapour barrier.
10 Drywall
MARTIN MITTELSTAEDT, DEAN TWEED/THE GLOBE AND MAIL
SOURCE: WWW.HOMESBYGREENING.COM
