This blog post examines the West Don Ravine Passive House in Toronto, Poiesis Architecture’s response to the vulnerabilities exposed by the 2013 ice storm.
It explains how this 3,000‑square‑foot, PHIUS‑certified home pairs rigorous Passive House performance with thoughtful site integration, local materials, and ecological landscape design to create a model for energy‑efficient, climate‑resilient urban housing.
Design and site response: fitting a Passive House into a ravine setting
Set into a hillside that faces a ravine, the house follows the land’s slope and minimizes its street presence while opening toward expansive natural views.
The form is deliberate: a planted lightwell pulls southern daylight deep into the interior, strengthening the occupants’ connection to greenery and daylighting without compromising thermal performance.
The project is an instructive example for urban infill and hillside lots where exposure, privacy, and microclimate demand careful integration of architecture and landscape.
Poiesis Architecture prioritized both a low visual profile and generous glazing toward the ravine to balance openness with energy efficiency.
Materiality and landscape as part of the Passive House strategy
Locally sourced materials — Ontario ash and pine millwork, Algonquin limestone pavers, and glazed terra‑cotta — give the interiors warmth and texture while celebrating local craft and structural honesty.
Personal elements such as knotty pine and a repurposed granite island introduce family history and sustainable reuse into the material palette.
The landscape strategy is as integral as the building envelope.
Terraces step into native plantings and a planted lightwell channels sun into living spaces, while a deliberate effort to replace 70 percent of former hardscape with soil restores habitat and storm‑water capture along the ravine edge.
Performance and systems: how Passive House standards drive comfort and resilience
The West Don Ravine Passive House demonstrates that stringent energy targets need not lead to closed, lifeless buildings.
Passive House principles shaped envelope and mechanical design from the outset, producing a project that dramatically reduces energy demand without sacrificing daylight or views.
Envelope, mechanicals and measurable outcomes
The build achieves an airtight, highly insulated shell with R‑50 insulated walls and an R‑80 roof. A continuous air barrier cuts heating demand by more than 85 percent.
Triple‑glazed windows and limestone pavers provide thermal mass and reduce temperature swings. Terraces and native plantings soften the transition between interior and exterior.
Two heat pumps and an energy‑recovery ventilator (ERV) provide efficient year‑round conditioning and fresh air. The house can hold near 54°F for days during power outages, indicating its resilience.
Key performance and design highlights include:
Here is the source article for this story: This Passive House in Toronto Was Designed to Withstand Extreme Weather—Even If the Power Goes Out