High-performance homes   (Page 2 of 3)

Why isn’t Canada spearheading the movement to build more sustainable homes?

By Monte Paulsen with photography by Grant Harder

Photo: Grant Harder

Public interest in energy conservation waned as quickly as the sticker shock of $1-per-gallon gasoline wore off. In the mid-1980s, Prime Minister Brian Mulroney slashed funding to Canada’s fledgling building science programs, and residential energy demands soon reversed a long decline. Between 1990 and 2007, per-household energy consumption increased by 13 percent.

The Saskatchewan Conservation House was sold, the solar thermal collectors were scrapped, and a garage was added. Saskatchewan’s landmark high-performance home appeared headed for that uniquely Canadian dustbin where such promising inventions as the Avro Arrow and the TurboTrain are sent to die. The house may have been forgotten forever were it not for the interest of a quirky German physicist.

Wolfgang Feist studied the Saskatchewan house along with other early superinsulated homes in Denmark, Sweden and the United States. Feist then wrote a mathematically precise and elegantly simple formula for designing high-performance buildings. His standard sets two hard limits: airtightness must meet or exceed 0.6 ACH@50Pa, and total energy use for heating and cooling must not exceed 15 kilowatt hours (kWh) per square metre of floor area.

Feist and colleague Bo Adamson dubbed their formula the “Passivhaus” standard because these buildings were too well insulated to require an “active” furnace or boiler. Compared with conventional construction, most Passivhaus buildings reduce energy consumption by 80 to 90 percent. (The German word has since been anglicized to the less precise Passive House.)

The first Passivhaus building, a row of four townhouses in Darmstadt, Germany, was erected in 1991. Feist’s formula quickly went viral. Today, there 900 buildings certified to the Passivhaus standard and roughly 32,000 Passivhaus-type buildings. The greatest numbers are in Germany and Austria, while the rate of growth is faster in Belgium and the United Kingdom.

Canada’s first Passive House arrived in 2009. It was prefabricated in Austria and assembled in Whistler, B.C., for use by the Austrian Olympic Committee and Austrian Public Broadcasting during the 2010 Olympic Winter Games. Afterward, the Austrians donated the 250-squaremetre building to the municipality of Whistler for use as a cross-country ski lodge. The Lost Lake PassivHaus (formerly the Austria House) uses about one-tenth the energy of a similarly sized conventional building. That worked out to a heating cost of about $280 last year.

“Passive House is the most economical way to build today if the operational costs over many years are taken into the equation,” says Guido Wimmers, a director of the non-profit Canadian Passive House Institute, which trains architects and builders. Canada’s second certified Passive House, a three-storey duplex overlooking the Rideau River in Ottawa, was finished in 2010, and Wimmers counts 40 more Canadian projects now under way. “Passive House is easy to understand,” he says. “And once understood, it becomes a no-brainer. People don’t want to build anything else.”

Across the valley from Whistler’s Lost Lake, Matheo Durfeld stands on the balcony of the community’s second Passive House, a townhouse-style duplex that may be Canada’s most affordable high-performance home.

Durfeld is a “wood guy.” He started out building log homes, then moved on to the lucrative business of crafting custom homes for Whistler’s tony ski set. A soft-spoken Canadian of Austrian descent, he’s given to self-deprecating humour. When asked why the Austrians hired him to help assemble their Olympic project, he quips, “Maybe it was only because we speak German.”

Whatever the reason, that gig transformed Durfeld and his tight-knit crew. He formed a company called BC Passive House, bought a lot in a subdivision called Rainbow and hired Vancouver designer Alex Maurer to prepare plans. Durfeld even traded his giant pickup truck — the time-honoured totem of the custom-home builder — for a tiny red Fiat.

“We’ve been in the custom-home business for years and know that we can build really nice houses if people have lots of money,” says Durfeld. “What we wanted to show here was that you can build a really efficient house without being a multi-millionaire.”

Durfeld’s duplex is an international mash-up — a West Coast wood guy’s reinvention of an Austrian interpretation of a German formula based on the original Saskatchewan house. The prefabricated wall panels are made entirely of Canadian wood products: two-by-ten frames are covered with oriented strand board (OSB) on the interior and a more breathable type of particleboard on the exterior side. The panels are packed with cellulose fibre insulation, then sealed tight at Durfeld’s shop in Williams Lake, B.C.

These outer walls were trucked to the site, hoisted into position and joined within a couple of days last fall. Once assembled, every seam and screw hole was carefully taped. This taped OSB forms the vapour barrier, a critical component of the “house as a system” approach. But while most Canadian homes are lined with a flimsy polyethylene vapour barrier that’s been punctured by thousands of staples and screws, as well as dozens of plumbing and electrical penetrations, the BC Passive House vapour barrier remains intact. A two-by-four service wall is site-built inside the superinsulated structural panel, and all wiring and plumbing lines are routed through this inner wall.