Project Profile: Deep Energy Retrofit in downtown Toronto
Seeking a new abode within walking distance of their architectural firm, Solares Architecture, as well as local schools, shops and transit, Christine Lolley and Tom Knezic entered into the highly-competitive Toronto property market to find the perfect place to retrofit and call their own.
As the co-founders of an architectural firm that delivers affordable, visually stunning and energy efficient designs, both Christine and Tom sought a property that warranted a complete top-to-toe retrofit overhaul. Their goal was to take a totally inefficient structure and transform it to meet the same high standards of energy efficiency and performance that they deliver to their clients.
A diamond in the rough
After searching for the right house for their personal residential project, Christine and Tom found their ideal candidate in the neighborhood of Roncesvalles Village in Toronto’s inner west. A rough-around-the-edges but solid home, the total floor space was only 900 sq. ft. (excluding the basement that they planned to rent out) meaning some clever design techniques were needed to ensure the home was not only comfortable for their young family of four, but also performed optimally throughout the year.
Upon possession in July 2013, the pair conducted an energy audit of the house. With a EnerGuide rating of only 38, the house was ripe for a total energy performance overhaul.
A ‘Deep Energy Retrofit’
Christine and Tom were eager to start living in their new home as soon as possible so had given themselves a very tight time frame of nine months to complete the deep energy retrofit.
Stripping the structure back to the bare bones, the only features of the home that remained were the brick walls, roof and floor joists. The basement was lowered by three and a half feet to accommodate a gravel base, four inches of insulation and a further four inches of poured concrete with an in-floor radiant system.
The old enclosed porch was removed and rebuilt while the original stairs were shifted from the northeast corner of the house to the southwest corner.
By way of insulating the building, the duo had decided on using spray foam insulation due to its insulating, air-sealing and energy efficiency properties. To reduce thermal bridging, 2x4 wall studs were built an inch away from the brickwork at intervals of 24 inches. Working with licensed Icynene spray foam contractor, Callrich Eco Services, four inches of Icynene closed-cell spray foam was installed into the walls to achieve R27.
Between the roof joists, six inches of Icynene open cell, light density spray foam insulation was installed under six inches of polyiso. The combination of closed cell foam in the walls and open cell foam ensured that the home had a truly airtight building envelope.
In the end, the retrofit took the original EnerGuide rating of 38 to an impressive 83. The clever design and careful curation of building materials, like Icynene spray foam insulation, helped the home achieve an 84% reduction in energy use as well as 92% reduction in space heating. Pre-retrofit, the home’s annual greenhouse gas emissions weighed in at 22 tonnes.
Following the renovation, Christine and Tom were able to cut emissions by a staggering 15 tonnes.
Finally, thanks to the inclusion of Icynene spray foam insulation in the walls and roof, air leakage was reduced by a remarkable 71%.
Christine and Tom’s clever and efficient design has not gone unnoticed. The retrofit project has received positive coverage from national Canadian newspaper, The Globe and Mail as well as from green news website, Treehugger. Additionally, the home has been featured on the Apartment Therapy website as well as the site’s House Tours series. Christine and Tom are expecting to see further coverage of their deep energy retrofit in coming months.
For more information about this unique retrofit project, visit the Solares Architecture blog.
CREDITS: Photography by Derek Monson for Solares Architecture.