How Terrebonne is built
- Before 1961 5%
- 1961–1990 45%
- 1991–2000 16%
- 2001 or later 34%
Why the design temperature matters in Terrebonne
−26.1°C is the 13th-coldest design temperature of the 70 cities we cover. The F280 calculation works out how much heat each room loses on that design day, from the house's actual walls, windows, air leakage and ceiling insulation.
At −26.1°C, a cold-climate heat pump sized to the calculation can carry most of the season, and the number shows how much backup heat the coldest days need.
In the Montréal area, 54% of households heat mainly with electric baseboards, 15% with a heat pump, 10% with a forced-air furnace and 6% with a boiler and radiators; electricity is the main heating energy for 71% of households, natural gas for 5% and oil for about 2% (Statistics Canada, 2023).
Terrebonne's hot summers make the cooling side count too. CSA F280 covers cooling capacity as well as heating, so ask for both numbers: a heat pump sized only for winter can be too big for summer, which leaves rooms cool but clammy.
What CSA F280-12 asks for
The National Building Code 2020 requires the heating capacity for a house to be worked out with CSA F280, and its list of referenced documents names the 2012 edition, CSA F280-12. Provincial codes can name their own edition and climate values, so ask your designer which ones the calculation uses.
Why skipping it costs money
Contractors who size by square footage routinely oversize. An oversized heat pump costs more to buy, cycles on and off, dehumidifies poorly in summer and wears faster. An undersized one leans on backup heat. The F280 report is the evidence either way, and it's worth having before you compare quotes.
What it costs
About $150–$400 as a standalone calculation (a September 2026 planning range; quotes vary). Many energy advisors bundle it with an EnerGuide evaluation, which also gives the calculation measured air-leakage data instead of an assumption.
Great Lakes–St. Lawrence Southern Ontario and southern Quebec
What this means in Terrebonne’s climate
Cold winters and hot, humid summers: seal the attic, dry the basement, plan cooling.
Why it matters here: Prevents oversized equipment that short-cycles and dehumidifies poorly, and is needed to choose the right heat pump.
Best timing: Before replacing an air conditioner or furnace, based on the house after planned upgrades.
- Right-size cooling to control humidity. In humid summers, an oversized air conditioner or heat pump cools quickly but shuts off before removing moisture, leaving rooms clammy. A heat pump replacing the air conditioner also covers much of the heating. Ask: Ask for a room-by-room heat-loss calculation and a duct and airflow check before replacing your air conditioner or furnace.
What else homes in Terrebonne need →
Sources for this climate guide · checked October 26, 2026
- National Building Code of Canada 2020, climate data (NRC)
- Canadian Climate Normals 1991–2020 (ECCC)
- Keeping the Heat In (NRCan)
- Air-Source Heat Pump Sizing and Selection Guide (NRCan)
- Heating and Cooling With a Heat Pump (NRCan)
- Heat pump basics (NRCan)
- Gas and heat pump hybrid systems (NRCan)
- Primary heating systems by household, Table 38-10-0286-01 (Statistics Canada)
- Electricity price comparison, April 2025 (Hydro-Québec)
- Canada's top weather stories of 2018 (ECCC)
- Canada's top weather stories of 2022 (ECCC)
- Canada's top weather stories of 2023 (ECCC)
- Canada's most impactful weather stories of 2024 (ECCC)
- Canada's top weather stories of 2025 (ECCC)
- 2024 Cross-Canada Survey of Radon Exposure
- Guide for Radon Measurements in Homes (Health Canada)
- Conditions for thermal scans, ASTM C1060 summary (Cx Associates)
- Canada's top weather stories of 2021 (ECCC)
NRCan-licensed service organizations serving Terrebonne
In Quebec, EnerGuide evaluations for existing homes run through the provincial Rénoclimat program; the organizations below are the ones NRCan lists for Terrebonne postal codes.
A service organization is a company that Natural Resources Canada (NRCan) licenses to deliver EnerGuide evaluations; its registered energy advisors do the home visit. Many energy advisors also do room-by-room CSA F280 calculations for an extra fee; HVAC designers do them too. Ask for the F280 report itself, not just an equipment recommendation.
- Expertbâtiment Services-Conseils
- Expertise en batiment Champagne
- Les Services ecoPlus
- Habite-Co 2000
Heat pump programs in Terrebonne
Heat loss calculation in Terrebonne: common questions
What design temperature is used for heat pump sizing in Terrebonne?
NRCan's HOT2000 climate data gives −26.1°C for L'Assomption (21 km away). Your designer may use the building code's design value for Terrebonne, which can differ slightly; ask which one the calculation uses.
What is CSA F280-12?
The 2012 edition of CSA F280, Determining the required capacity of residential space heating and cooling appliances. The National Building Code 2020 requires heating capacity for a house to be determined with it.
How much does a heat loss calculation cost?
About $150–$400 standalone as a planning range; often less when bundled with an EnerGuide evaluation.
Who does F280 calculations in Terrebonne?
Many of the 4 NRCan-licensed organizations serving Terrebonne offer them, as do HVAC designers. Ask for the F280 report itself.
Do rebate programs require a heat loss calculation?
Requirements vary by program and change often. Even where it isn't required, it is the best protection against an oversized or undersized system.