he major renovation of this original 1800s Toronto house, built by Equinox Developments, maintains the heritage quality of the exterior while updating the interior to a bright, contemporary home. A technical challenge of this project is achieving an air-tight, well-insulated envelope without using spray foam. While spray foam can be seen as an energy efficient retrofit solution (3-in-1 air barrier, insulation and vapour barrier), some types have significant environmental impact from manufacturing and installation. Instead, this project uses a new, avant-garde alternative for the air barrier: a rubberized, liquid-applied, vapour-permeable membrane by Henry Bakor, applied to the interior face of the brick. This creates a continuous barrier that can be tested and modified before the house is finished, resulting in superior efficiency and interior comfort.