The walls of a 1950s Toronto house are usually empty. Filling them does not mean opening them.
We locate the studs and any fire blocking, because a cavity with a blocker halfway up is two cavities and needs two holes. Then roughly two-inch holes, one per bay per storey, drilled from outside through siding or brick where we can and from inside where we must. Injection foam goes in wet and expands to fill the cavity, around wiring and pipes where batts never could. Holes are plugged and the wall made good.
Not if the cavity already holds batts — foam cannot displace them and you get voids. Not on a balloon frame with no fire blocking, where the fill cannot be controlled. Not where water is getting into the assembly. And not if you are re-cladding within a year, because exterior insulation done at the same time is a better wall for less combined cost.
Walls are not on the no-assessment stream. They pay only through the assessment pathway, which needs an energy advisor before and after and at least two upgrades together. A typical empty 2x4 cavity filled with injection foam lands in the R–12 to R–20 band, which pays up to $2,100.
Amounts are set by Enbridge Gas and Save on Energy and are quoted from the programme pages — attic stream, assessment stream — checked September 2026.
In brick, mortar-matched plugs are visible close up. In vinyl or aluminium siding the courses come off and go back and nothing shows. In stucco, patches show until repaint.
Slightly, as it cures, which is why the fill is done to a measured density and checked. Anyone promising zero shrinkage is not being straight with you.
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You get the depth, the tier, the dollar figure and the photographs, whether or not you go ahead with us.
