Old house gets new tricks after energy-saving retrofit

Something old, something new, something borrowed, something green?

On Glen Manor Drive, an eco-friendly construction company is wedding new energy-saving techniques to a nearly 100 year-old house. They are borrowing tree shade to help cool it in summer and relying on “green” materials — such as straw-bale walls — to keep it warm in winter.

From the street, the two-storey, Tudor-style house at 168 Glen Manor looks like many of its neighbours, with leaded windows and a timbered gable under the peaked roof.

But inside, Mick Paterson, a site manager with The Fourth Pig construction, showed Beach Metro News how the retrofit and addition are making the old house more energy efficient than many new ones.

Standing by the front windows, Paterson said all the windows in the home are now triple-glazed, so they transfer less heat.

On the living room floor, he pointed out the new electrical outlets — the old ones were mounted along the wall. Like the home’s new kitchen fan and clothes dryer, neither of which need outdoor air ducts, having outlets in the floor means the house has fewer gaps in its exterior walls where heat can leak in or out.

By plugging leaks, wrapping the house with thicker brick and straw-bale walls, and preferring heated floors and radiators over a forced-air system, Paterson said the Glen Manor house is now far more airtight. A recent fan test showed that with all its doors and windows sealed, air cycles through the house just twice an hour – less than half the rate of a conventional Ontario home.

“We’re pretty proud that we got that low,” Paterson said, noting that it’s far harder to make an older home airtight than it is to design and build a new one from scratch.

“There was a house done recently, all new construction, and before they put the drywall down they were down to 0.4 air changes per hour,” he said.

“They say that’s tight as the space shuttle.”

Besides the brick and straw walls that hint at the nursery rhyme behind their name, Paterson said The Fourth Pig also uses expanding foam insulation.

Foam does have a downside — it gives off some toxic gases as it dries — but on balance, he said it’s a more eco-friendly material than many of the paints and glues people typically in homes.

“Some people don’t want to know that the paint they’re putting down in their basement is toxic as hell, or the glues they use in their cabinets are really toxic.”

Passing through the original first-floor rooms, where workers were busy refinishing the existing oak, poplar, and Douglas fir woodwork, including reused doors and trim, Paterson stepped into the new finished addition. Made with straw-bale walls, it extends the rear of the house about five metres.

“We’re the only ones to have built straw bale homes in Toronto,” said Paterson, adding that they are more common outside Peterborough, Ottawa, and Kingston.

While using unwanted straw from nearby farms strikes some as “too hippy-ish,” Paterson said after the three-foot bales are stacked behind wood boards and plastered with a mix of lime, sand, plaster of Paris and marble dust, the finished walls have a smooth, enamel-like feel and an R-30 insulation value more than double that of a conventional build.

“I started looking into this maybe 15 years ago,” said Paterson. “You keep hoping people will pick up on it. It seems like it’s getting there, it’s just slow.”

Andrew Peel agrees that Canada lags behind other countries in developing more energy-efficient homes, but says it’s slowly catching up.

Peel, who consults and certifies low-energy buildings, worked for several years in Germany and the UK with the Passivhaus Institut, a German-based organization that sets a high standard for building efficiency. He is now the only “passive house” certifier in Canada.

Unlike other efficiency models, such as “net zero” homes, Peel said the passive house standard relies less on solar, wind, or geothermal technologies. In some ways, it expands on a trend started by Canada’s R-2000 standard, developed in the 1980s.

Most of the efficiency gains in a passive house come from insulating materials and good design, he said, though most do use a special ventilator that recovers heat as it moves air in and out of the building.

Such ventilators work quite differently than a furnace, he said, which has to recirculate air at high volumes, mostly because air has such a low capacity for retaining heat.

“With a passive house, you can reduce the demand enough that you can heat the air without using recirculation,” he said.

Peel said a newly built passive house in New Brunswick has achieved cost-neutral status, meaning the higher mortgage payments its owner pays for the extra-efficient home are offset by lower energy bills.

And in Vancouver, a developer is considering plans for an 81-unit condo that meets the passive house standard — the first of its kind in Canada.

“It’s expanding outside of single-family homes,” said Peel.

“It’s on people’s tongues more and more.”

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