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From the outside, Canada's greenest house is unremarkable — just another dwelling in a massive subdivision in Guelph, Ont. In fact, it's extraordinary, and putting it together was a challenge that caused the builder, Reid's Heritage Homes, to rethink its relationships with the tradespeople it works with.
Part of a 750-home project on the southern outskirts of Guelph, the residence is one of the first in Canada to be certified under a new program called "Leadership in Energy and Environmental Design (LEED) for Homes," developed by the U.S. Green Building Council (USGBC). The house that Reid built is not only certified, it's certified at the platinum level, the highest rating. (Simple LEED certification, and the silver and gold ratings come before it.)
That the house is an unassuming structure is deliberate.
"It had to feel like a normal home and look like a normal home from the street," says Andy Oding, product development manager at Reid's. The company wanted to see if it could build such a house while maintaining appeal to the people who buy houses in subdivisions. So instead of designing from scratch, they modified one of their best-selling designs.
This green home was built to look like the others in the neighbourhood. (GLENN LOWSON FOR THE GLOBE AND MAIL)
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But the changes that make this ordinary house extraordinary meant working more closely with the trades. It also meant building differently, and to do that, they needed the trades to not only do things differently, but to understand why. "We found that in building this home … it's no longer acceptable for a builder to say to a trade, 'This is what we want, go build it,'" Mr. Oding says. "You have to take on the role of educator."
A big part of improving energy efficiency is improving insulation and air sealing. In addition to beefing up insulation, the installers also had to understand that the two-inch-thick rigid foam sheathing on the exterior had to be sealed everywhere. Drywallers had to be instructed not to break the vapour barrier with their zip tools (the little routers used to tightly cut around electrical boxes).
Framers needed to understand the process so the house wrap would form a tight seal.
The process was a two-way street, Mr. Oding explains. The company needed certain things done differently, and the trades came up with new ways of doing things that the company hadn't thought of.
One big difference was the ductwork. The duct layout is different in order to have more efficient heating and cooling while using 30 per cent less material. They used a special insulated duct that is tightly sealed. This was the first time a Canadian builder had used it, but the installers quickly discovered that the material goes together quickly and has fewer sharp edges to work with than the standard material. That meant fewer cuts and injuries. For the homeowner it has the added benefit of being extremely quiet.
"When you get into building sustainable, the light has to come on and the builder or trade has to understand that this is just building better. That's a key component," Mr. Oding says.
When builders start working on green buildings, they often find new and better ways of doing things. In part, that's because they actively re-think the way they build and actively seek out and share new ideas. It's also partly because they become exposed to new technology. For example, the Guelph house has a device to capture heat from the drain stack. It's a simple, inexpensive addition that saves up to $200 a year, the builder says, because water passes through pipe coiled around the stack before going to the water heater. It's a little thing, but so effective that Reid now uses it on all their houses.
"Green home building is simply a better way to build a home," says Ashley Katz, spokeswoman for the USGBC. "You're using the highest performing materials, the most innovative strategies and technologies, as well as established, proven design features and technologies that lead to a high-performing green home."
While the house was designed to look like the others in the subdivision, and be just about the same to live in, it is quite unlike most suburban homes. The changes required to get LEED platinum certification cost about $150,000 extra, including about $45,000 to $55,000 for energy-related components. But the improvements will also cut the household operating expenses for a five-person family to about $900 a year from about $4,500, the builder says. A bit more solar power and that figure would go down further.
The big differences aren't the visible ones, which include sustainable materials such as cork and bamboo flooring. Many are inside the walls — beefed-up insulation, including two inches of foam sprayed under the concrete slab basement floor. The floor joists are further apart, with thicker oriented-strand board on top, glued and screwed down. Changes such as this cut lumber use by almost one-third, the builder says.
In the basement, the furnace runs almost silently. The geothermal system draws on heat from the rock deep under the house for heating and cooling. It regulates the house's temperature year-round. In the summer, it pumps heat back into the earth, where it is stored. That, in turn, makes winter heating 16 per cent more efficient, the builder says.
Perhaps the most interesting addition to this green house is one that gardeners will love. The lawn was seeded with drought-resistant fescue, and there's an automatic drip irrigation system that uses rainwater, primarily for the flower beds. The system is hooked up to a weather satellite and also measures humidity in order to determine when to water. Rainwater is also used in the toilets and, thanks to a special permit, it also gets heated for use in the washing machine and dishwasher.
When it rains, water drains into a cistern, though the first millimetre is drained off as waste because it contains most of the detritus that will run off through the eaves. The system is currently being monitored and evaluated by students at the University of Guelph.
At the end of the day, the extra $150,000 investment produces a house that looks like any other, is roughly the same as any other to live in, but is more efficient and much less expensive to live in.
Some of the new techniques and elements will be taken to the builder's new subdivision near Owen Sound, Ont., which will comprise 800 to 1,000 LEED-certified units. They won't have all the bells and whistles of the platinum house in Guelph, but they will have some, such as under-slab insulation, R50 attic insulation, grey water recovery and the drain stack heat exchanger. Model homes are scheduled to open in July.
Special to The Globe and Mail
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