To determine the number of BTUs per square foot that you need to heat a room, simply multiply the square footage by 20 BTUs per square foot. For example, if a room has 1,000 square feet, you would require 20,000 BTUs to heat it.

How many BTU do I need per square foot?

As a rule of thumb, an air conditioner needs 20 Btu for each square foot of living space. But other considerations, such as the ceiling height and the size of your windows and doorways, might call for more cooling power. To measure your room, multiply the length by the width.

How many BTUs do I need to heat 1500 square feet?

A 1,500-square-foot home will require between 45,000 to 90,000 BTUs.