Project spotlight: Passive House, Net Zero Energy Laneway Housing University of Toronto

PBC members undertake projects across Canada and all members can submit their projects to be highlighted in our news section (contact tech@passivebuildings.ca)

Completed Fall 2020 The University of Toronto Laneway project, designed by BSN Architects, won a SAB award for best small residential project nationwide in 2021. Local Impact Design was Passive House Consultant, energy modeler and structural/HVAC engineer.

The project is exemplary in a number of ways, proving the concept of pre-fab + Passive House + net zero energy. Passive House methodology was adopted to optimize both energy and lifecycle cost. Shell consists of R-45 prefabricated wall panels from Build Smart, Thermapan R-54 Structural Insulated Panels (SIPs) for the roof, and Alpen Passive House triple glazed windows (R7) and a shallow super-insulated foundation system (R-24) by Legalett.

The prototypes use an earth-tube system to pre-condition ventilation air in conjunction with heat recovery ventilators. In winter, the earth tube preheats the ventilation air by as much as 15°C, providing up to 4,000 BTU/h of free heat. In summer and shoulder seasons, the earth tube pre-cools fresh air into the building by about 7°C as well as removes moisture (humidity) to the point where mechanical cooling is not required.

The Infill House is “smart ventilated” with a Build Equinox CERV2 automated ventilation system that monitors indoor air carbon dioxide and total VOC (Volatile Organic Compound) concentration levels. The unit works on demand ventilation, only ventilating when required. The infill home uses only 33% of the total annual electricity that an equivalent house designed to the Ontario Building Code (OBC) would consume. Despite using standard heat recovery ventilators (HRV’s) and electric baseboard heaters (for cost and space reasons), the Laneway Houses use only half of the annual energy of an equivalent Code-built home.

Designed to achieve net-zero annual energy, the buildings incorporate solar PV panels by Guelph Solar, both on the roofs and south wall of the 3-storey laneway house. Total annual generation for the 18 kW system is estimated to be 20,075kWh, slightly above the projected annual energy use of 19,767kWh.

For more information contact: Blair Jurecka blair.jurecka@utoronto.ca