Project Leo achieves both net-zero and Passive House performance without a traditional furnace even in -40C temperatures. The secret to keeping the home warm without a furnace lies in its advanced, super-insulated walls. The build team crafted a 12-inch double-stud wall system packed with R50 insulation. On the inside, they added a second 2×4 wall layer. This extra layer acts as a service cavity for wires and plumbing and ensures that no utility cuts ever puncture the home’s air-tight outer shell. To round out this highly efficient exterior envelope, the home features PHI-certified Defender 88PH+ Pro windows and doors. These were specified for their ability to meet the rigorous airtightness and thermal performance requirements of the Passive House standard.

Instead of relying on a fossil-fuel heating system, Project Leo captures and repurposes everyday energy. Sunlight pours through the large windows to heat the concrete floors, while body heat and running appliances help keep the air warm inside. To keep the air fresh and clean without losing that precious warmth, the home uses a high-tech Heat Recovery Ventilator (HRV). The HRV continuously pulls fresh air from the outside, pre-heats it using the warmth of the outgoing stale air, and circulates it through the rooms. This setup keeps the indoor air incredibly healthy while reducing heat loss to almost zero.