Basement Insulation Toronto

Closed-cell spray foam is the ideal basement insulation because it serves as both an insulation and a moisture barrier in one application. Unlike fibreglass batts, which absorb moisture and promote mould growth in basements, closed-cell spray foam repels water, prevents condensation, and delivers R-6.0 per inch. It adheres directly to foundation walls, eliminating air gaps where moisture can collect.

Basement spray foam insulation in Toronto typically costs between $3,000 and $7,000, depending on the size of your basement, wall height, and whether rim joists are included. A standard 1,000 sq ft basement with 2 inches of closed-cell spray foam on the walls and rim joists usually falls in the $4,000-$5,500 range.

The Ontario Building Code requires a minimum of R-20 for basement walls in new construction. For renovations and retrofits, we recommend at least R-12 to R-20 depending on the depth of the foundation below grade. Closed-cell spray foam at 3 inches delivers approximately R-18, which meets most requirements.

Yes. Cold floors above an uninsulated or poorly insulated basement are one of the most common complaints we address. Insulating basement walls and rim joists with closed-cell spray foam raises the overall basement temperature, which in turn warms the floors above. For slab-on-grade situations, we can apply spray foam under new flooring assemblies.

Closed-cell spray foam significantly reduces mould risk in basements. Because it is a vapour barrier, it prevents warm indoor air from reaching the cold foundation walls where condensation would otherwise form. Mould requires moisture to grow, and by eliminating condensation, spray foam removes the conditions mould needs to thrive. It is also inorganic and does not provide a food source for mould.

If you have fibreglass batts with a poly vapour barrier on your basement walls, we recommend removing them before applying spray foam. The poly traps moisture against the foundation wall and can hide mould growth. Removing it allows spray foam to bond directly to the concrete, creating a superior seal.