Aluminum Windows in Toronto.

Built for Toronto’s climate

Lake Ontario keeps Toronto's winter air moving back and forth across the freezing line more often than a purely continental city sees, and that back-and-forth is what actually works a window seal loose over a few seasons, more than a steady deep freeze would. The spec answer is the same one any zone 6 winter calls for: a low U-factor and a triple-pane unit with a warm-edge spacer, insulation value doing the work rather than a coating built for a cooling-dominated climate. Toronto's summers run humid too, which puts condensation control on the interior face of a well-sealed frame back on the list, a swing between a sticky July and a hard January few climates ask a single window to handle. The Victorian and Edwardian houses through Cabbagetown, Rosedale, and parts of Forest Hill also tend to carry window openings that drifted from standard sizes across a century of additions and settling, and some sit inside a heritage conservation district where exterior sightlines get reviewed before a swap goes ahead, confirm that with your local heritage committee before ordering. Newer infill and Leaside two-storeys want the identical cold-climate glazing spec, just in a more regular opening. Order inside the April to June window, generally, before install crews and weather line up against you.

Climate zone

NBC Zone 6 (cold-humid)

Best time to spec

April to June

What we plan for

freeze-thaw, humid summers, and cold winters