Blossom Park Apartments

Lead Proponent

Indwell Community Homes

Project Objectives

The objective of the Project is to support the construction of a new 34-unit high-performance Multi-Unit Residential Building (‘MURB’) to be constructed as part of the Proponent’s affordable housing portfolio using a prefabricated panelized envelope. The Project supports Program Objectives by driving down the cost and creating market confidence in net-zero energy ready construction.

The building will be designed targeting Passive House Classic and net-zero energy ready performance levels. It will target an estimated 10% incremental cost compared to a similar building built to local current code levels. The Project will demonstrate that the net zero energy ready design is achievable and within a 10% incremental cost to an existing code-compliant building by leveraging the prefabricated high-performance wall assemblies.

Results

Construction of the Blossom Park multi-unit residential complex was completed in 2020. The building follows the Passive House approach of high levels of insulation and a focus on air sealing the building envelope. For the walls, Indwell used the Build SMART prefabricated wall panel system, built offsite in a controlled factory setting and delivered to be assembled at the building site. Passive House-certified triple-pane windows and insulated, thermally-broken doors were selected to complete the envelope. To ensure airtightness, a quality assurance program was put in place, including training for sub-contractors and periodic inspections of envelope detailing.

Heating and cooling is provided by a variable refrigerant flow (VRF) air-source heat pump located in an underground space, with intake and exhaust dampers providing ventilation to the outside. When outside air temperatures are low, the dampers close and the heat pump pulls heat from the underground room, ensuring the heat pumps continue operating at high efficiency. In extreme cold, an auxiliary gas furnace can heat this space. Four Energy Recovery Ventilators (ERVs) ensure a continuous supply of fresh air to the housing units while reducing energy lost to the outside, with one ERV supplying common areas and running intermittently, reducing energy use. Small fan-coil units are used to condition the individual housing units.

These design elements came together to enable the building to meet Passive House standards, achieving 0.54 ACH, 14kWh/m2/a heating demand and 1kWh/m2/a cooling demand. This represents a 70% energy reduction and 69% GHG emissions reduction compared to building to typical Ontario Building Code standards. Indwell estimates that this performance was achieved at a 6.7% incremental cost over typical construction.

Benefits to Canada

Thanks to Indwell and the Blossom Park project team, 34 residents have a safe, affordable, and comfortable place to call home. Indwell estimates the low-carbon energy systems of Blossom Park will reduce emissions by 900 tons of CO2 per year, compared to a similar-sized code-built building. Most importantly, Blossom Park will serve as a demonstration of one potential pathway for highly efficient multi-unit residential buildings leveraging prefabricated envelope elements.