How to calculate the number of BTUs needed to heat a house? - GestionAir

How to calculate the number of BTUs needed to heat a house?

Heating a house requires energy. The BTU (or British Thermal Unit) is still often used in North America to quantify this energy. Technically, a BTU corresponds to the amount of energy needed to raise (heating) or lower (cooling) the temperature of one pound of water by one degree Fahrenheit.

Increasingly, the kilowatt (kW) is becoming the standard measure. As a point of equivalence, one kW is approximately equal to 3412 BTUs. Manufacturers of heating/cooling appliances indicate the power in BTUs and in kW for each of their models.

Determining how much energy (in BTUs) is necessary to heat a single-family home is important. It affects the comfort of the occupants and the durability of the installed system. In the case of a heat pump, choosing a model with insufficient power will overwork the device (with a risk of faster wear). In cold periods, such a model may not be able to maintain the rooms at the desired temperature. Whereas, a model that is too powerful means an unnecessary higher cost at purchase, as well as poor dehumidification in cooling mode (hence the risk of discomfort).

BTUs Based on the Characteristics of Your House

Several variables must be considered when calculating the number of BTUs needed. These include the total surface area of the house (in square feet), the height of its ceilings, the number and quality of its windows, the level of its insulation, its orientation relative to the sun, its exposure to wind, and the climate of the region in which it is located. While this may seem like a lot, fortunately, there are charts today that simplify the process. For example, for the power of a heat pump, there is the CSA-F280-FM90 standard.

The experts at GestionAir can calculate everything for you

In general, it can be said that in warm zones, you should multiply the square footage of your home by 10 to 15; in intermediate zones, by 20 to 30; and in cold zones, by 30 to 40. Thus, in Quebec, a 2000 square foot house may require up to 70,000 BTUs (2000 x 35) for heating (including during periods of extreme cold). Depending on your needs, our experts will use a relevant calculator to determine the right choice for your heating and air conditioning appliances.

If you need more information about BTUs or if you have any other questions, please do not hesitate to contact us.

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