Guelph Deep Energy Retrofit

This major Deep Energy Retrofit, completed in early 2017, marks a change of lifestyle for our clients, a newly retired couple with two adult children. The couple, previously living in Brampton, Ontario, decided to make the change to a car-free, sustainable lifestyle. The couple had originally thought of buying a plot of land and building a brand new house. However, after contacting Solares, who suggested a move to Guelph, for its walkability and train links to Toronto, decided to instead fully renovate a lovely century-old cottage in picturesque downtown Guelph, within walking distance to lots of amenities and green space.

To keep costs low and maintain the original structure’s aesthetic and charm, the major renovation used all the original structure’s window openings, only adding one opening for a large window in the great room and one for a rear exterior door. Two small additions were removed from the building completely, and the basement was underpinned considerably to allow for a full guest suite for the couple’s relatives who often visit from Switzerland.

The finished renovation is amazingly airtight, with an air change rate of 1.3 ACH@50pa. With an Energuide rating of an impressive 82, this house performs among the top 5% of buildings in its type.

The house is one storey tall with a basement guest suite. The front door opens to a hallway with a long closet along one wall. Off this hallway is the master bedroom, with the home’s main floor bathroom en suite. The hallway opens to the main living area, situated in the Great Room. A small office is tucked into the front of the home, accessible off the Great Room, for added privacy. Beyond the living area is the spacious kitchen, with a central table and windows on all three walls. At the kitchen’s far end, a new rear door leads to the backyard.

The basement includes a guest suite, with a kitchenette, a bathroom, and a bedroom, for visiting family and friends to enjoy on their typically extended stays. Also located in the basement is the mechanical room.

The home is designed with passive solar techniques, with large amounts of southern daylighting for maximum heat gain, two exterior doors at either end of the house for natural cross-ventilation, and fully operable tilt-and-turn windows.

The home is conventional stick framing, and the majority of materials used in this project were easily accessible and found locally in Guelph. The only exceptions to this were the IKEA kitchen cabinetry, bathtub, and triple-glazed fiberglass windows, which came from Hamilton, Brampton, and Toronto, respectively. By sourcing materials locally as much as possible, the transportation requirements were reduced, which drastically lowers the project’s embedded energy.

In the walls, 6 inches of foam was sprayed between the studs. The foam was chosen specifically for its low GWP (Global Warming Potential), since spray foam, though incredibly efficient as insulation, can be detrimental to the environment through its manufacturing and installation process. However, the spray foam insulation chosen has a GWP of nearly zero, making it both efficient and environmentally friendly. The structure is very well insulated, with values of R35 in the walls, R20 in the basement slab, and R60 in the roof.

The home’s heating system is custom designed using electric baseboards, which is an unconventional choice in a sustainable home as they can be costly and inefficient. However, due to this project’s airtightness and high levels of insulation, the heating requirements are extremely low, and nearly all of the heat produced by the baseboard system is retained. Due to the home’s minimal heating loads the system’s operating costs are kept low, and the low installation cost helped keep construction within budget. Each baseboard unit is linked to its own thermostat, which allows the residents to freely control the heat in each room. Thanks to the home’s passive solar design, there is no need for air conditioning.