It is a roofer’s term for 100 square feet of roof surface. When you get a price for a new roof, the contractor may say something like “the roof is about 28 squares and will be $8,000.” The area of roofing that is quoted in squares will be much more than you might expect for three reasons:

1) Homes usually have two different square footages listed on a realtor’s listing sheet or the tax appraiser’s property records. One is the conditioned (heated and cooled) living area, and the other is the total area under roof. A typical home that the owners know as being 1800 square feet may also have a 450 square foot twocar garage, plus front and back porches that total another 300 square feet, for a total of 2500 square feet under roof.

2)But that’s just the beginning. That 1800 square foot house typically has a two foot roof overhang that adds an average of 250 square feet of roof, for a total of 2750 square feet.