2 Answers

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Determining how many BTUs are necessary for a particular building is an art and a science. A typical house should have a heating system that can muster between 30 and 60 BTUs per square foot of floor space. Builders use systems toward the higher end of the range in the colder regions of the U.S. and they use systems toward the lower end of the range in the warmer regions. So, at best, the calculation of the recommended BTUs for your heating system is an estimate

Calculate the total BTUs your heating system should generate by multiplying your square footage by the BTU range you selected in Step 2. For example, if you live in a 2,000-square foot home in the far north, you will need a heating system in the 55-to-60 BTUs per square foot range.

Lower BTU estimate = 55 BTUs/ft^2 x 2,000 ft^2 = 110,000 BTUs

Higher BTU estimate = 60 BTUs/ft^2 x 2,000 ft^2 = 120,000 BTUs

Your heating system should generate between 110,000 and 120,000 BTUs to adequately heat your home. This is a rough estimate, and you should consult a heating professional to obtain a more definitive number.