Toronto Method Test Shed
Residential Construction Method for a Toronto Climate
Sustainable is literally pushing the envelope.
Toronto’s climate challenges how we construct our homes and buildings. We have very cold, dry winters and hot, humid summers, which places great stress on our building envelopes. Imagine a typical winter day when it is 21°C inside, and -10°C outside. That’s over a 30°C difference that your wall and roof has to manage by keeping the heat in – no wonder that our building envelopes are stressed!
The challenge: to reduce the heat loss of our homes using a thin and efficient wall that is suitable for Toronto’s narrow properties. Traditional homes are wood-framed, either 2x4 or 2x6, and filled with batt insulation – if at all. We have been building our homes this way for over a century - not because it makes sense, but because “this is the way that it’s always been done”, and our thinking has not evolved to suit the current rising cost of energy and expectations for occupant health and comfort.
Modern building science has evolved our understanding of how buildings perform, and has led us to a few realizations; we don’t use enough insulation, and heat loss through the studs is greatly reducing the effectiveness of the insulation that we do use. Many houses in Ontario are seeing the value in adding an inch or two of exterior insulation, but that is just the beginning. At Sustainable , we have a dream. We see the future of the building envelope in cold climates like Toronto, and it follows these simple principles:
1. There is only ONE CONTINUOUS MEMBRANE wrapping the structure, that will improve air-tightness and better manage liquid water and vapour.
2. More insulation! And more effective insulation – i.e. insulation that is on the EXTERIOR of the structure, improving its effectiveness and increasing the lifespan of the wood structure by keeping it warm.
3. Use a durable, lightweight cladding to protect the wall from extreme weather. Vent behind the cladding to increase drying potential of the wall.
In order to realize our vision, the team at Sustainable has built a test structure using these simple principles. We’ve called it the Toronto Method. The test structure has been third-party tested by Ryerson University Master of Building Science students to verify its effectiveness, improve constructibility, and fine-tune it for use on future projects.
Location: Toronto, ON
Area: 35 sq.ft.
Project Leads: Craig Race, Kelsey Saunders
Insulation Provider: Roxul
Weather/air Membrane Provider: Henry/Blueskin
Contractors: Modus Homes, Greenbilt Homes
Window Provider: Ridley Windows and Doors
Building Products Provider: Herrmann's Timber-frame Homes