To calculate square footage you need to know the dimensions of whatever you are measuring. Multiply the length by the width. A room 11' x 5' would have a square footage of 55 sq.
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1. Measure one side of the box with yardstick or measuring tape. Write this number down. 2. Measure the other side of the box in the same manner, writing this number down as well.
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Square feet measure area. The formula will depend on what you want to know the area of.
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1 Determine the square footage of each room to be heated or cooled. Most rooms are either rectangular or triangular in shape. Rooms that aren't either of these shapes can be broken
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