New Brunswick · Energy · checked September 28, 2026

Heat loss calculations in Saint John

The heat loss calculation is how a heat pump or furnace gets sized for your house, and the key input is the design temperature: −22.5°C for Saint John, from NRCan's HOT2000 climate data for Saint John.

Get matched in Saint John → The CSA F280 heat-loss calculation
A kitchen table with a house floor plan, a laser measure, a tape measure and a laptop showing the plan

Design temperature

−22.5°C

The cold day heating is sized for

Heating degree-days

4,580

A long heating season

Standard

CSA F280-12

The national method for sizing heating and cooling

Typical cost

$150–$400 standalone

How Saint John is built

Saint John's houses by when they were built Ten house shapes, one for each tenth of Saint John's 19,705 houses. Before 1961: 34%, 1961–1990: 44%, 1991–2000: 9%, 2001 or later: 13%. Older houses glow hotter.
  • Before 1961 34%
  • 1961–1990 44%
  • 1991–2000 9%
  • 2001 or later 13%
Each house stands for one in ten of Saint John's 19,705 houses (single-detached, semi-detached, row and duplex), drawn by when it was built. The glow shows the usual pattern: older houses tend to be leakier and less insulated. More snow in the drawing means more heating degree-days: a longer, colder heating season. Sources: Statistics Canada 2021 Census (table 98-10-0233-01), NRCan HOT2000 climate data.

Why the design temperature matters in Saint John

−22.5°C is the 27th-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 −22.5°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 Saint John area, 38% of households heat mainly with electric baseboards and 32% with a heat pump; electricity is the main heating energy for 46% of households (Statistics Canada, 2023).

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.

Atlantic Canada Maritimes and Newfoundland

What this means in Saint John’s climate

Damp, windy, icy winters and costly oil: switch to heat pumps, seal, test for radon.

Atlantic winters are wet, windy and icy rather than extremely cold, and summers are mild. Heating oil is still common and its price rose sharply in 2026, while heat pumps already heat many homes. An EnerGuide evaluation here should plan the move off oil, seal wind-driven leaks, fix moisture before insulating, and include a radon test.

  • Plan your move off oil. Oil prices rose 65% to 81% in a year, and corrosion is a leading cause of oil tank leaks. Cold-climate heat pumps can be up to three times as efficient as oil heating. Ask: Ask the advisor to note your oil tank's age and condition, and to size a cold-climate heat pump with a backup plan.

What else homes in Saint John need →

Sources for this climate guide · checked October 26, 2026

NRCan-licensed service organizations serving Saint John

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.

Source: NRCan list of licensed service organizations, checked September 28, 2026. Call to confirm your street is covered and ask about wait times.

Heat pump programs in Saint John

Provincial · needs an evaluation New Brunswick Total Home Energy Savings Program Evaluation-first: $99 + HST covers both home energy evaluations, then published incentives such as $1,500 for a ducted heat pump, $0.40–$0.85 per sq ft for attic insulation and $250–$550 for air sealing Open Federal National Heat Pump Rebate Announced October 8, 2026 and opening early 2027: up to $10,000 below the median income, $2,000 for other eligible homeowners Announced · opens 2027 Federal CMHC Eco Improvement premium refund A 25% energy-efficiency rebate on your CMHC mortgage insurance premium after $20,000 of energy renovations Open

Heat loss calculation in Saint John: common questions

What design temperature is used for heat pump sizing in Saint John?

NRCan's HOT2000 climate data gives −22.5°C for Saint John. Your designer may use the building code's design value for Saint John, 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 Saint John?

Many of the 4 NRCan-licensed organizations serving Saint John 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.

Heat loss calculation near Saint John

Heat loss calculation in Fredericton81 kmHeat loss calculation in Moncton123 kmHeat loss calculation in Halifax204 kmHeat loss calculation in Charlottetown247 kmHeat loss calculation in Lévis431 km All 70 cities →

Sources

Checked September 28, 2026. Census figures are for the municipality (New Brunswick); climate data is NRCan's HOT2000 station Saint John (11 km away).

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