Pushing the (building) envelope
Housing today accounts for 15 per cent of Canada's greenhouse gas emissions. While the housing industry has made strides in improving energy efficiency, there's a need to move towards building homes that are substantially more efficient. Custom builders have been developing net-zero homes — those that annually produce as much energy as they use — and a new initiative from the federal government is geared towards helping higher-volume production builders to also incorporate net-zero technologies in their mainstream construction projects.
The ecoENERGY Innovation Initiative (ecoEII) is allowing for the construction of 25 net-zero-energy homes in four provinces. As one of the builders involved in this initiative, Mattamy Homes has committed to building five net-zero homes in Calgary.
How can Mattamy design and apply energy-efficient construction systems, methods and technologies for building net-zero homes that are both tough enough for the Alberta climate and affordable for the average buyer?
Work with SAIT's Green Building Technologies (GBT) research team to identify and use cost-effective and high-performing building-enelope technologies and systems, and to help train both tradespeople and home inspctors on their use.
According to Warren Saunders, Mattamy's vice president of sales and marketing and a graduate of SAIT's Architectural Technologies program (‘89), SAIT's previous work on net-zero homes in Alberta's climate has made it a highly valuable partner in the ecoEII project. SAIT has worked with Mattamy, he says, not only to determine the best buildingenvelope design — one that acts as a superb thermal barrier so comfortable temperatures are maintained — but to also offer troubleshooting, adjust construction sequencing and provide guidance to tradespeople.
"A net-zero home is a living, breathing building system that only works well if all the parts work together. It's not really one size fits all — that's the challenging part of it," says Saunders.
The first of the 1,658-square-foot homes was completed in November 2015 and the remaining homes have been carefully designed so Mattamy can replicate net-zero lessons learned during construction. Each model has the same footprint, roof and dimensions. Ultimately how the houses perform, however, depends on how people live in them, so SAIT will work with the buyers of each of Mattamy's five net-zero homes to monitor and test energy performance over two years.
SAIT's David Silburn, Green Building Technologies Research Associate, says the biggest challenge hasn't been the technology, it's been working to adapt
and to streamline new construction processes to ensure they're cost effective.
For SAIT, he says, the project has been an excellent opportunity to be a part of early stage commercial application of net-zero technologies and extend education to industry stakeholders outside of the classroom.
"Hopefully what we're doing will help raise the bar for the future of home building in this country. It can only help homeowners and consumers — all of us —in the future."