If Vancouver aims to become the world's greenest city, where are all the ultra-energy-efficient Passive House buildings?
Passive House is the ultimate standard in preventing energy waste. In fact, this kind of house doesn't even need a central heating source. It's virtually airtight; its walls are over twice as thick as normal and packed with insulation; its triple-paned windows are sited to absorb the most possible light and heat, and every "thermal bridge," down to the smallest pipe or wire, is prevented from transferring heat or cold into or out of the building.
The heat comes from the people in the house and the appliances and lights they're running. Meanwhile, the air quality is superlative because of sophisticated ventilation that brings new air into the home and warms it with recycled heat from outgoing air. There are thousands of these buildings in Europe, where Passive House started in the late 1970s.
So why don't we see any here?
We will soon. Five Passive House-certified projects are being developed in Vancouver. It's an informal race to see which is the first one built and that will depend on which project can get through the permit process at city hall the fastest.
"We've got two in for permit and so I think at that level we're ahead of some other folks," says Bryn Davidson of Lanefab Design/Build. "But whoever gets there first, I think it's a win for everybody."
"The main thing is just dealing with the City," he says. "That's what we've been engaged in pretty heavily: talking about the process and how to remove the barriers to green building."
Davidson was one of the experts addressing Vancouver City Council recently on the Greenest City 2020 Action Plan. Monte Paulsen, of Red Door Energy Advisors and the Canadian Passive House Institute West, was another presenter talking about the benefits of Passive House technology.
He says, "About 55 per cent of the greenhouse gas emissions in the city are from buildings, and small buildings are the worst offenders. In the vast majority of houses, duplexes, townhouses and small commercial buildings, the heating load is going to be two-thirds of the total energy. So if you want to address the largest chunk of the largest emitter of greenhouse gases, you want to look at how not to spend so much heat on building."
The sticking points
Paulsen says there are three major issues that pit Vancouver bureaucracy against ultra-high-efficiency buildings.
Wall thickness:The City of Vancouver includes the thickness of the wall in the calculation of floor area. Normal house walls are eight or nine inches, but Passive House walls are 14 to 17 inches thick. As Bryn Davidson says, "If you do a thick wall assembly then you're potentially facing a huge penalty in floor space. In Victoria they just count the floor area inside the wall, so it doesn't matter if you do an eight-inch-thick standard wall or a 17-inch-thick Passive House wall."
Design guidelines:City bylaws that encourage character flourishes like pitched roofs and attached balconies make it difficult to build to Passive House standards. The first principle is that the structure has to be boxlike, with plenty of large windows facing south and fewer facing north.
Paulsen believes the bylaws were well-intentioned. "These bylaws sought to turn the tide against a sea of Vancouver specials and include more character features," he says. "We're in conversation with the city about how we can preserve their objectives the connection to the street, the character features but also make it possible to design more high-performance buildings at lower cost. When we add on lots of window boxes and bay windows and balconies over living spaces, we wind up creating building envelopes that are extremely convoluted and have an extraordinary amount of surface area compared to the original volume, and an extraordinary amount of thermal bridging, which causes heat loss."
Building height:Vancouver restricts height for single-family houses, yet encourages pitched roofs, creating upper storeys that are less usable and, as Paulsen says, "pushing the house down into the ground as far as you can because you're designing against that upper point."
"Say we could raise that upper point another four or five feet," says Paulsen. First, a lot of our basement suites would be ground level now and much more liveable and light filled. Second, our building costs would be a bit lower because a slab-on-grade foundation is much cheaper than a basement, and can be super insulated much more cheaply. Third, if you want to have a ceiling with 24 inches of insulation, you can do that."
Starting to see results
The battle with bureaucracy has been going on for some time. Bryn Davidson's company has built the houses with the highest Energuide efficiency ratings in the city, but not without a lot of push back over permits.
"For years we've been fighting battles, trying to do heat recovery or prefab wall panels or this or that," he says. "It's only because we're obsessed about it that we would spend all the time and money and energy that we've put into it trying to figure these things out."
Paulsen says, "We have a lot of these things to work out. The first-generation Passive House projects are not in Vancouver. There's one in Surrey, there's one in Langley, three in Whistler, two in Victoria, one in Fort St. John. The barriers to trying something new and the land costs are a little lower there, so there's just less risk."
However he is encouraged. "Vancouver recognizes this problem. There are people assigned to look at ways that the city can streamline things for deeply green buildings. And I think they'll find ways to deal with some of this.
"We would not be having this conversation if it weren't for this council trying to make us the greenest city by 2020. By setting out this goal they have raised these little conflicts because the left arm and the right arm of the city aren't always working together perfectly. We wouldn't even be focused on this if we weren't trying to build better, so I view this as a really nice first world problem."
Vancouver's 5 Passive House Projects
Duplex Tong Residence, by Marken Projects
2,800-sf new house on 33-ft lot, by Lanefab
2,800-sf 50s bungalow renovation, by Lanefab
Anonymous private residence
2,200-sf prototype house, by ONE Seed and Footprint Sustainable Housing
