The type of insulation required in exterior walls in Ontario,

The type of insulation required for exterior walls depends on your location, wall type, and local building code. In Ontario, most exterior walls in residential construction typically require:

• Batt insulation (fiberglass or mineral wool) between studs

• Rigid foam insulation on the exterior in some builds

• Spray foam insulation for higher energy efficiency and air sealing

Common wall insulation values are:

• 2x4 walls: usually around R-22 to R-24

• 2x6 walls: usually around R-24 to R-31

For basement or secondary suite projects, Ontario code often also requires:

• A proper vapour barrier

• Continuous insulation in some assemblies

• Fire-rated assemblies depending on the application