How many BTU for 1,500 sq ft?
Updated October 24, 2026
To heat 1,500 sq ft (139 m²) you need between 22,500 and 55,500 BTU/h depending on your city and insulation. Here is the calculation city by city, using the CSA F280 method.
Assumption: a 1,500 sq ft bungalow with no heated basement, 8 ft ceilings, windows in proportion to floor area.
Heating load by city and house age
| City | After 2010 | 1990 to 2010 | 1970 to 1990 | Before 1970 | Cooling* |
|---|---|---|---|---|---|
| Vancouver (-7 °C) | 22,500 | 22,500 | 22,700 | 29,800 | 13,700 |
| Toronto (-18 °C) | 22,500 | 22,500 | 31,400 | 41,100 | 15,600 |
| Halifax (-16 °C) | 22,500 | 22,500 | 29,800 | 39,100 | 13,200 |
| Montreal (-23 °C) | 22,500 | 24,000 | 35,300 | 46,300 | 14,600 |
| Quebec City (-26 °C) | 22,900 | 25,600 | 37,700 | 49,400 | 13,700 |
| Winnipeg (-31 °C) | 25,300 | 28,200 | 41,600 | 54,500 | 14,600 |
| Edmonton (-32 °C) | 25,800 | 28,800 | 42,400 | 55,500 | 13,200 |
* Cooling for a 1990–2010 house, at the city’s summer design temperature.
Which Kanartic system for 1,500 sq ft?
Newer house in Toronto
Z-PRO 27,000 · 2 zonesfrom $4,725 · DIY
Covers 100% of the heating load at -18 °C
See on kanartic.ca1990–2010 house in Montreal
Z-PRO 27,000 · 2 zonesfrom $4,725 · DIY
Covers 100% of the heating load at -23 °C
See on kanartic.caPre-1970 house in Edmonton
ZERO 24,000 wall unit + ZERO 24,000 wall unitfrom $6,798 · DIY
Covers 86% of the heating load at -32 °C
See on kanartic.caWhat about 25 BTU per square foot?
The rule of thumb would give 37,500 BTU/h for 1,500 sq ft. The component calculation gives 22,500 to 55,500 BTU/h: depending on the house and climate, the rule is off by −32% to +67%.
Frequently asked questions
Is a 12,000 BTU heat pump enough for 1,500 sq ft?
In Montreal, for a 1990–2010 house, a 12,000 BTU unit covers 50% of the load at -23 °C; for a pre-1970 house, 26%. So you need a bigger unit or backup heat.
How many BTU to cool 1,500 sq ft?
Between 13,200 and 15,600 BTU/h for a 1990–2010 house, depending on the city. In Canada, heating sets heat pump size, not cooling.
Wall unit or multi-zone for 1,500 sq ft?
At this size, a multi-zone puts one indoor unit per floor or large room, connected to a single outdoor unit.
Other floor areas
1,200 sq ft1,300 sq ft1,400 sq ft1,600 sq ft1,800 sq ft2,000 sq ftAll
How many BTU for my house?Why not to oversizeHeat pump costBy room