Lethbridge is the windiest city in Canada, and that single fact reshapes the value of a spray foam quote here. Wind drives cold air through every gap a static climate would forgive - so in Lethbridge, the air-seal you're paying for isn't a bonus, it's the whole point. With about 59% of homes built before 1991, most of that stock leaks badly under a constant wind load.
How the number is built
Quotes are per board foot - area x thickness x foam type: - Closed-cell (R-6 to R-7, vapour barrier) usually earns its premium in Lethbridge's wind-loaded older walls and basements. - Attic R-38 is roughly 6 inches closed-cell or 11 inches open-cell. - Access changes labour - an open build in Riverstone versus a retrofit in an older core home.
Why wind changes the math
Under relentless wind, air leakage is continuous, so the savings from sealing compound faster than in a calm climate. That's why a Lethbridge retrofit quote for an older, leaky home often pays back quicker than the sticker suggests.
Estimate board feet, then get an exact Lethbridge quote. See cost drivers province-wide.