Ratings & sizing
Manual J
ACCA's industry-standard residential heat-loss/gain calculation — the right way to size HVAC equipment.
Manual J is a software-based calculation accounting for every wall, window, door, ceiling, occupant, and air-leakage path in your home. Output: the BTU/hr the home actually needs at design heating and cooling temperatures.
Why it matters: a Manual J typically sizes equipment 25–40% smaller than the "rule of thumb per square foot" method. The right-sized unit runs longer cycles, dehumidifies better, costs less to run, and lasts longer.
We do a Manual J on every install — it takes ~30 minutes with the home's blueprints or a quick measurement. If a contractor quotes you replacement equipment without one, ask why. The free quote becomes very expensive when the wrong-size unit costs $400/year more in fuel for 18 years.
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Mississauga, ON · Greater Toronto Area and up to 2 hours out — London, Kitchener, Barrie, Kingston, Niagara.