How to Calculate How Many BTUs You Need to Heat Your Room
- 1). Measure the size of your room with a tape measure. You will need measurements for the room’s length, width and height.
- 2). Determine the cubic feet in the room by multiplying the room’s length by its width by its height.
- 3). Multiply the cubic feet by 5 if your room is well-insulated. If your room has a large number of windows and doors or it is not well-insulated, multiply by 6. If the room faces north, multiply by 7. The sum will be the minimum requirement for BTUs to properly heat your room.
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