How Many BTUs Per Square Foot Are Needed When Sizing a Home Furnace?

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The BTU of a home furnace should typically average between 40 to 45 BTU pre square foot, though this average applies only to homes located in cooler climates. Square footage measurement is generally considered a rudimentary calculation and can yield a large range of results.

When choosing a home furnace, it is important to get the correct size to maximize its effectiveness. An oversized furnace generally will often turn itself off and result in a larger electricity drain when it has to be turned on again. An undersized furnace can fail to sufficiently heat up a house while at the same time constantly draining electricity.