Ontario construction costs in 2026 are rising unevenly. Statistics Canada's Building Construction Price Index rose about 4.2 percent year over year in its most recent readings, but steel-heavy scopes are running far hotter: structural steel framing and plumbing each climbed nearly 12 percent, driven partly by 50 percent US Section 232 tariffs on steel and aluminum disrupting North American supply chains. Wood framing is the relief: softwood lumber futures sit roughly 60 percent below their 2021 peak despite added duties. Industry estimates put hard construction costs for a downtown Toronto high-rise near $390 per square foot. Against that, development charge relief programs worth billions are cutting the government-fee side of project budgets, so the 2026 pro forma question is scope-specific escalation, not a single inflation number.
The single most misleading thing you can do to a 2026 pro forma is apply one escalation number to the whole budget. Ontario's cost picture this year is a spread, not an average: steel-heavy scopes are inflating at close to triple the headline index while wood framing is cheaper than it has been in years, and the largest government-fee relief programs in a generation are pulling soft costs down at the same time.
| Cost driver | Direction | Detail |
|---|---|---|
| Building Construction Price Index | Up ~4.2% year over year | Statistics Canada residential composite, most recent readings |
| Structural steel framing | Up nearly 12% | Tariff-disrupted supply chains; equipment-heavy scopes similarly exposed |
| Plumbing and mechanical | Up nearly 12% | Metals content and equipment pricing |
| Softwood lumber | Down ~60% from 2021 peak | Futures near $551 per thousand board feet versus the $1,419 peak, despite added duties |
| US Section 232 tariffs | 50% on steel and aluminum | Applied to full customs value; ripples through North American pricing even for domestic buyers |
| Development charges | Down sharply where programs apply | Toronto cutting 40 to 60 percent; $8.8 billion federal-provincial partnership funds cuts of roughly half elsewhere |
Two forces explain most of the spread. First, tariffs: the United States applies 50 percent Section 232 tariffs on steel and aluminum and a further layer of duties on Canadian softwood, and even projects buying domestic material feel the repricing as North American supply chains re-sort. Second, demand: with GTA high-rise starts falling, trade availability has improved and competitive tension on tenders has returned in some scopes, which is why the composite index is rising slower than its steel-heavy components.
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Check my site →Cost indices lag and tariff policy moves quickly. Confirm current material pricing with your cost consultant or key trades, and current DC treatment with the municipality, before locking a pro forma.
The composite Building Construction Price Index rose about 4.2 percent year over year in its most recent readings, but the spread by scope is wide: structural steel framing and plumbing each climbed nearly 12 percent while softwood lumber remains roughly 60 percent below its 2021 peak. Budget by scope rather than applying one number.
The US applies 50 percent Section 232 tariffs on steel and aluminum and additional duties on Canadian softwood lumber. Even Ontario projects buying domestic material feel the effect, because North American supply chains reprice together. The most exposed lines are structure, mechanical, and any equipment-heavy scope.
Industry estimates put hard construction costs for a downtown Toronto high-rise condominium near $390 per square foot, with low-rise wood-frame product substantially cheaper. Costs vary widely by site, structure type, and finish level, so treat any per-square-foot figure as a screening number, not a budget.
Yes. Softwood lumber sits far below its pandemic-era peak, improved trade availability has returned competitive tension to some tenders as high-rise starts fall, and development charge relief is the largest in a generation: Toronto is cutting DCs 40 to 60 percent and the $8.8 billion federal-provincial partnership funds cuts of roughly half in participating municipalities.
Size it to your scope mix. A wood-frame low-rise with locked lumber pricing can carry a conventional contingency, while a steel-structure project with open procurement should stress-test the steel scopes at plus 10 to 15 percent and size contingency to survive that case.
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