Which heat pump for which room?
Updated October 24, 2026
Every room has its quirks: foundation walls in the basement, a big door in the garage, windows everywhere in a sunroom. Pick yours.
Basement
800 sq ft in Montreal: 12,000 BTU/h · ZERO 12,000 wall unit
Garage
400 sq ft in Montreal: 9,300 BTU/h · ZERO 12,000 wall unit
Cottage
1,000 sq ft in Montreal: 26,400 BTU/h · Z-PRO 27,000 · 2 zones
Sunroom
200 sq ft in Montreal: 4,400 BTU/h · ZERO 9,000 wall unit
Bedroom
150 sq ft in Montreal: 2,300 BTU/h · ZERO 9,000 wall unit
Open concept
800 sq ft in Montreal: 12,000 BTU/h · ZERO 12,000 wall unit
Compare rooms
| Room | Area | Montréal | Toronto | Edmonton | System (Montreal) |
|---|---|---|---|---|---|
| Basement | 800 sq ft | 12,000 | 12,000 | 12,000 | ZERO 12,000 wall unit |
| Garage | 400 sq ft | 9,300 | 8,300 | 11,200 | ZERO 12,000 wall unit |
| Cottage | 1,000 sq ft | 26,400 | 23,500 | 31,700 | Z-PRO 27,000 · 2 zones |
| Sunroom | 200 sq ft | 4,400 | 3,900 | 5,200 | ZERO 9,000 wall unit |
| Bedroom | 150 sq ft | 2,300 | 2,300 | 2,300 | ZERO 9,000 wall unit |
| Open concept | 800 sq ft | 12,000 | 12,000 | 12,000 | ZERO 12,000 wall unit |
For a single room, one wall unit is almost always enough. Differences between rooms of the same size come from exterior walls, windows and ground contact: a glassed-in sunroom often needs twice as much as a bedroom. For several rooms, the calculator’s room-by-room mode splits the load and suggests a multi-zone.
Frequently asked questions
How many BTU for a 300 sq ft room?
4,500 to 6,600 BTU/h depending on the city, insulation, exterior walls and windows. A 9,000 BTU wall unit easily covers a room that size.
Can one heat pump heat several rooms?
A wall unit heats an open area well. For closed rooms or several floors, a multi-zone puts one indoor unit per room, connected to a single outdoor unit.