Residential (Small) Award
Jury Comment: Given the requirement to maintain the historic character of the neighbourhood, and the imperative to add density by creating a duplex, meeting Passive House performance at this scale is a remarkable achievement. This project should be an inspiration for others like it in Vancouver and elsewhere.
A rare Canadian example of a Passive House EnerPHit retrofit, this duplex was fashioned from a 1940s single-family home. The original home had been in the same family since the 1950s and had recently been gifted down to the grandson and granddaughter of the original owner. They decided to convert the house into a duplex, keeping one half each, but also decided to upgrade it to meet Passive House standards.
Development in much of Vancouver’s Kitsilano neighbourhood is subject to character retention guidelines; and balancing the required upgrade to Passive House thermal performance with the need to maintain architectural heritage was very challenging. However, by choosing to renovate rather than demolish the house and build new, the owners were able to retain more than 60% of the original framing material.
This dramatically lowered the embodied carbon of the building. By adding new structure to the existing framing, it was possible to bring the house up to current structural and seismic standards, while using far less new material than would have been required in an all-new building. Less new material, also translated into less construction waste.
It was necessary to lift the house to install a new crawl space basement which acts as a mechanical room and storage space. To further reduce embodied carbon, a ‘concrete free’ basement slab was installed, constructed with two layers of 15mm plywood laid directly on rigid insulation and compacted gravel.
The completed duplex is fully electric, with both electric heating and hot water. Rough-ins for air-to-air heat pumps were also made for future space cooling if needed. As summers in Vancouver are getting warmer, space cooling may become necessary for comfort in many buildings. The duplex is expected to use approximately 14 kWh/m²/year and is Passive house certified. Triple pane PH-certified wood windows are used within a wall assembly that consists of 2×6 framing with 4” of exterior mineral wool insulation.
The house uses triple pane Passive House-certified windows and doors by VETTA Building Technologies Inc.
A Mitsubishi Electric Sales Canada ductless heat pump handles heating and cooling.
- Architect DLP Architecture
- General Contractor Geography Contracting
- Photos Michael Renaud
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