The 'greenest house' at the Games
Austria Passive House uses natural energy for heating, cooling
Norbert Gleirscher is all smiles as he welcomes a group of visitors at the front door of Austrian Passive House, a 3,000-square-foot feat of engineering unlike any other in Canada.
The "passive house" is engineered to heat and cool itself through thick insulation, solar energy, ground heat and an airtight building envelope. That makes this Whistler, B.C., building — home base for Austrian Olympic officials, media and athletes during the Games — 90 per cent more efficient than the average Canadian home.
"This is the greenest house," says Gleirscher, project manager for the Tyrolean Future Foundation, a consortium of companies and Austrian institutions that led the construction. "It is the first and only one [in Canada]."
The Austrian foundation's goal in building the $1.3-million house was to showcase what's possible in energy-efficient construction, even in a wintry Canadian climate.
"There is a sense the Austrians have created magic," says Matheo Durfeld, a Whistler contractor whose fluency in German and expertise in building log homes helped him land the job of assembling Passive House.
"We [Canadian builders] understand the technology. Austrians have just made a science of it." The house, designed so that it could house a family of five, took three months to construct, with materials arriving from Austria in September and the house erected by November.
How it all works
The secret, Durfeld says, is to eliminate thermal bridging. Thermal bridging occurs when a material inside the building acts as a temperature conduit between the interior and exterior.
Because a house's concrete slab foundation has sections that lie outside the walls, the slab will get cold in the winter and carry that cold air inside. Even the dirt a house sits on, and the wiring and copper plumbing that run through its foundation, can lead to heat-sapping thermal bridging.
Unlike typical concrete, wood or masonry construction, Passive House is completely insulated from the outside, a design that eliminates thermal bridging. No part of Passive House is in contact with the outside elements. The entire foundation is built inside an insulated, air-tight box.
A brown lining
Passive House is not entirely green. The materials used to build the house, including the wood (a dense alpine variety of pine native to the Tirol region of Austria) and all the house's interior contents were shipped from Austria in eight large freight containers.
The team used Austrian material because they were donated by Austrian companies. If Canadian materials had been used, the project's costs would have skyrocketed.
"It was weak environmentally to ship everything over," project consultant Guido Wimmers concedes.
However, he says, the goal is to showcase a high-efficiency building. Anyone wishing replicate the idea in the future could use local materials and make the home much greener.
In winter, the ground temperature is warmer than the air. A network of water-filled pipes running a few meters below ground pick up the extra heat from the ground and transfer that into the house through radiant flooring.
In summer, when the ground is cooler, the same system works to bring down the house's interior temperature.
The rest of the building's heat comes from the sun. Its south-facing wall, which gets the most sunlight, is filled with windows. Its north side is virtually windowless. In the summer, thick black blinds cover the south-facing windows, blocking the hot sun. When the blinds aren't needed, they fold up into the ceiling.
In the winter, additional warmth is generated from electrical appliances such as computers and lights, combined with the movement of people. Heat is also stored in the building's wood frame and dense stone flooring.
The system is effective. In the winter, if it's -15 C outside, it will be 15 C inside. On a milder winter day, inside temperatures soar above 20 C.
While there is no thermostat, the temperature can be set by adjusting the speed that water flows through the house's floor pipes. Ventilation fans, running on a low level of electricity, circulate air from the ceiling.
In total, it requires only four kilowatts of energy to heat the entire building. Gleirscher says the average Canadian home uses 400 kilowatt hours per square foot per year, while Passive House uses just four kWh per square foot per year.
"It's really nice… you touch the ground and it's a comfortable [temperature]," says Luc Delestrade, a visitor to Passive House. "When you stand by the window, it's not cold. These are good qualities."
'Right place at the right time'
When it came to choosing to build Passive House at the 2010 Olympics and in Whistler in particular, Gleirscher said it was a case of being at the "right place at the right time."
The Olympic organizers had a focus on sustainability and the environment, which local officials in Whistler enthusiastically have embraced. That focus fit perfectly with Passive House's goals.
"We thought very much about how we could use the Games as a way to showcase sustainability … and we're thrilled at what [Austria Passive House] offered us," Whistler mayor Ken Malemed says.
Passive House will long outlive the Vancouver Olympics.
After the Games, the house will be given to the municipality of Whistler, which donated the land for the project, and paid for the piping and utilities. It is intended to be used as a rental shop and club space for the Whistler Off Road Cycling Association (WORCA) and the Whistler Nordics Ski Club.
The Whistler Blackcomb Foundation contributed $150,000 to the $1.3-million project to ensure that legacy.
Builder Durfeld is just happy to see the house up and running. He says now that he's built one green home, he's tempted to do more.
"I've been living and breathing this project," he says. "[I'm] thinking this is maybe something [I'm] going to start. Its about the transfer of technology and that's whats going on here."
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