By David Dodge & Dylan Thompson
In 1976, gas prices doubled overnight. Naturally, this freaked many people out. In Saskatchewan, many complained bitterly to their government, who searched for an answer.
“The government asked the Saskatchewan Research Council (SRC) to design and build a solar house appropriate for Saskatchewan,” recalls Harold Orr, who, along with his SRC colleagues, went on to pioneer the passive house concept.
They called it Saskatchewan Conservation House. It was so new and so different, engineers from Germany and around the world came to check it out.
Today, Germany is the worldwide hub of Passiv Haus construction, while back in Saskatoon, work is nearly complete on the Temperance Street Passive House, what will be Saskatchewan’s first certified passive home.
Saskatchewan’s passive house roots
Back in the 1970s, when the Saskatchewan government tasked Orr’s team with powering a house with solar, the group quickly discovered a problem: storing the energy to heat a standard home would require enough water to fill two Olympic-sized swimming pools.
Orr realized they were approaching the problem from the wrong direction. So they flipped the idea on its ear — the answer was to radically reduce the home’s demand for energy.
“Draw a pie as the total consumption of a house,” says Orr. “You divide it in three equal parts. One third of it is losses through the windows, the walls, and the ceiling. One third is heat loss through the basement. And the other third is air leakage.”
So you insulate the heck out of the walls, ceiling and the foundation—problem solved!
“It’s like the difference between a coffeemaker and a thermos bottle,” says Orr. “A coffeemaker puts heat into it and keeps the coffee warm as long as you pay for the bill. But you fill the thermos and the coffee will stay warm for a long period of time, even overnight.”
With dramatic increases in insulation, all that’s left is to reduce air leakage. A conventional home loses so much heat through air leakage it may as well have a hole in the wall you could crawl through. To quantify this air loss, Orr invented the blower door test.
“That’s one of the requirements of all passive houses. They must have a blower door test, and they must achieve 0.6 air changes [per hour] at 50 pascals of pressure, which is very tight,” says Orr. “Conventional houses are between three, four, five. I did a house that had 11 air changes per hour, and we brought it down to less than two, which is remarkable for an old house.”
So the idea of a passive house was born, and as it turns out the model also inspired the net-zero energy home movement as well. While solar modules cost $77/watt in 1977, they are a hundredth of that price today, which means solar-powered super-energy-efficient homes are suddenly very doable.
Bringing passive house back home
Fast forward 39 years and Harold Orr met us at the Temperance Street Passive House, which will become the first certified Passive House in Saskatchewan.
Michael Nemeth is the 30-year-old founder of Bright Buildings, a consulting firm specializing in energy efficiency and passive house modelling in Saskatoon, Saskatchewan.
“The three most important principles for a passive house are super insulation, air tightness, and good windows towards the south,” says Nemeth. “With that, you’ll achieve a very energy efficient building.”
Robin Adair, owner of The Green Builder, is constructing the Temperance Street passive house. Nemeth and Adair met in 2014 at a passive house training session.
So efficient—it’ll blow your hair back!
“We’ve gone away from natural gas altogether,” says Adair, sitting on the gate of his truck on Temperance Street. “There’s no fossil fuel coming to the building. We’re using electrical energy and we’re going to supplement that and perhaps maybe produce all the electrical needs with PV solar.”
“It doesn’t need a furnace,” says Nemeth. “Because it’s so well-insulated and because the energy requirements are so low, we can heat with electric resistance and still only pay about $300 a year for that heating.”
Yup, no furnace. A 93-per-cent-efficient heat recovery ventilator and an electric heater about the size of two small hair dryers will heat the home just fine. Despite only being at the rough-in stage, the home achieved a remarkable 0.37 air exchanges per hour using the blower door test
Insulated to the nth degree
This is possible thanks to Harold Orr’s defining principles, which Adair and Nemeth have totally embraced.
The inside load-bearing walls of the Temperance Street Passive House look like normal 2×4 walls with plywood on the outside. The seams in the plywood are sealed and taped. Then there is a second 14-inch wall outside the first.
This exterior cavity is stuffed with blow-in insulation while the interior walls are filled with mineral fibre batts, which provide an insulation value of R65. The cool part is the plywood, which is a permeable vapour barrier. A special finish called Agepan DWD is applied to the outside. The finish is designed to draw moisture out of the wall and release it into the atmosphere.
The basement walls were constructed using insulated concrete forms (ICFs), but that’s only the beginning. Adair and Nemeth added 10 inches of polystyrene insulation outside the concrete to achieve R40. There’s also a full 12 inches of insulation under the basement pad.
Along with the R105 blow-in insulation in the attic you have a home that requires only 15 per cent of the energy to heat as a conventional home of similar size.
The Temperance Street Passive House
Originally, homeowners Holly Ann Knott and her husband Jim Spinney asked Adair to retrofit their existing home. However, it soon became clear the home wasn’t worth salvaging. Adair, looking for a chance to put his passive training to work, suggested they might try to do something innovative instead.
“It just made sense,” says Knott of hyper insulating the home. “You start with not constantly burning fuel. [In our old home], I always had these images of dollar bills just flying out the window. We’re not going to have a furnace. And that really blows [our friends] away.”
They have replaced their original single family home with a passive house duplex. They plan to sell half the house and live in the other half.
For Harold Orr, who received recognition as a pioneer of the Passive House concept from the German institute last year, it’s pretty validating to see his idea come back to Saskatchewan 39 years later.
It’s the start of something Robin Adair would like to see a lot more off, and Michael Nemeth agrees. “We have a need to reduce our energy use,” says Nemeth. “We have commitments made at the Paris Climate Change Conference for reducing our carbon emissions, and buildings are a third of the energy used in Canada. We can make huge strides in carbon reductions through building our homes and our buildings more energy efficiently.”
Michael Nemeth’s work on passive houses was recently recognized when he was awarded a $50,000 Quest Climate Grant from Shell and Canadian Geographic for his work on Saskatchewan’s first passive co-housing project.