Passive House in a box
Brookfield pilot project in Calgary to educate trades on sustainable construction methods and standards
In the community of Symons Gate, Northwest Calgary, an experimental Passive House is being built, straight out of a box, shipped from Germany. The house is being constructed by Brookfield Residential, headquartered in Calgary, as a pilot project to educate its trade suppliers on construction methods to meet Passive House Institute standards.
The Passive House Institute is the only internationally recognized performance-based energy standard in construction. A Passive House typically uses 90 per cent less energy than comparable new builds because of its efficient use of sun and shade, internal heat sources, passive cooling techniques and efficient heat recovery.
Indeed, it's so efficient it doesn't require a conventional heating system. The house under construction in Symons Gate has no furnace, a ventilation system supplies constant fresh air to the air-tight structure and a heat recovery unit allows for the heat contained in the exhaust air to be reused.
It will be the first home in Alberta certified by the Passive House Institute and Brookfield claims it will be one of the greenest homes constructed in the province to date.
"We wanted to experiment with the highest energy efficiency standard in the world and get a handle on it," explains Doug Owens, Brookfield's director of operations. "This is a pilot project. We know where energy efficiency codes are going in Canada over the next decade or two and this will shape the steps we take towards energy efficiency in the future."
Mr. Owens claims the build has given a number of suppliers an opportunity to gain experience in Passive House construction methods.
"Sawback Builders, who are a young framing company, they took on the assembly of the CLT [cross laminated timber]; Canyon Plumbing were excited to learn about the heat recover ventilating unit; and B.M.W. is the siding company that took on the external envelope," he says. "It's been a useful learning curve for everybody."
Upon completion, in October, the project will be used as a demonstration house for a year before being sold, although Brookfield has no immediate plans to start selling such homes as standard.
"We're looking to take aspects of it; the air tightness details, the exterior insulation, whatever we can, and incorporate it into the rest of our models to drive up the quality and energy efficiency of the homes we'll build in Alberta over the course of the year," Mr. Owens explains.
But he admits one of the "biggest challenges with the project so far" has been sourcing the materials to build to Passive House standard.
"Many of the components we need to build an energy efficient home of this standard are not readily available in Canada. So that makes it very expensive," he says.
"Heat recovery ventilation windows and triple glazed windows for example; there are some available in Canada but they're still not to the standard that we need to hit the energy efficiency targets we're shooting for," he continues.
Unable to source the whole package, at the standard they required, on home soil, Brookfield imported the majority of the components for the house in two sea cans from Austria and Germany. Including the walls, which are 16 inches thick CLT panels, engineered in Germany.
"CLT is a big growth area for Canada's construction industry and there's new CLT plants being built right now to support the opportunity passive building construction presents," Mr. Owens says. "In the future, we'd certainly like to be able to use more local suppliers but, in this instance, we wanted to minimize risk and go with one vendor and supplier for all components."
Passive House designer Tomaz Stich, who consulted on the project, says sourcing construction components locally is tricky. "CLT is available here but wood fibreboard, for insulating a CLT home, at the correct thickness for Passive House construction, isn't. I would like to see that come to market in Canada," he says. "Windows are obviously something we'd rather not have to import too but there's also a need for small things like tape and gaskets. It would be good to see these things manufactured more locally, certainly."
Rob Bernhardt, CEO of Passive House Canada, the Canadian affiliate of the International Passive House Association, believes sourcing locally manufactured components for Passive House construction is set to become a lot easier in the future.
"Last week, the federal government and provinces agreed on a national building strategy: Build Smart Canada. That document is an agreement to transform our buildings and develop high performance components, so that we aren't looking to import things like windows and ventilation equipment," he explains. "Among other things, that document commits to a long term goal of moving Canada's entire window industry to Passive Houses minimum level of performance."
"For countries to meet their Paris commitments, buildings need to be at this level of performance," he adds. "It's not just the environmental footprint it's the comfort, the air quality, the resilience; they're simply better buildings."
"Incentive programs … are going to drive this too. The government is going to fund demonstration projects for example. Energy benchmarking and labelling for buildings is also coming, so a building will have an energy efficiency label which will affect market value, because energy efficiency is taken as a proxy for building quality," he continues. "That gives buyers a basis for judging the quality of the building that they've never had before. In a competitive market, developers are unlikely to want to be selling a second-class product. And once developers start to build this way, local supply will grow."
Mr. Bernhardt says local manufacturers are already starting to emerge. "We have two Passive House window manufacturers in Canada currently and I know of two more about to launch. I know we're also soon going to have high performance ventilation units, previously only produced in Europe, manufactured in Canada," he says.
"It's clear the direction buildings are going and it's in developers' and trades' business interests to learn how to do it," he continues. "It's a more technical way of building and those with experience will have a competitive advantage. What we're seeing now is larger firms, like Brookfield, getting that experience."
Mr. Bernhardt says Passive House is unconcerned with the embodied carbon associated with importing building materials because "our focus is operational carbon. Wood tends to be very low carbon so importing CLT from Europe on a ship is probably still lower in embodied carbon than using concrete and steel."
But he is hopeful that Canadian suppliers and manufacturers will grasp the business opportunity that Canada's changing construction industry presents.
"There's millions of square feet of Passive House construction in the pipeline in Canada. It's rolling out at scale now and there's a wide variety of firms getting into it. It's a huge opportunity for Canadian suppliers."