The formula
For each line item we multiply a quantity by a national unit cost, then apply a quality-grade factor. A regional labor multiplier is applied to the labor portion only; materials are priced nationally. We show the itemized result as a ±20% range.
National unit costs
Regional labor multipliers
Each province's labor multiplier is its median carpenter wage relative to the national median, from the Government of Canada Job Bank wage data (Carpenters, NOC 72310) — used as a proxy because window installation has no dedicated Canadian occupation code, so carpenter wage is the disclosed labor proxy. Multipliers are bounded to a sane range and applied to the labor share of each line item, so materials stay nationally priced while labor tracks local wages.
Data vintage and limitations
Compiled June 2026 from public cost aggregators and government wage data. These are derived estimates, not live contractor quotes. Local prices vary with project complexity, access, and material availability; always confirm with a licensed contractor before budgeting.