How many squares is my roof?
A roofing square is 100 square feet of roof surface. Contractors price in squares, so knowing yours is the fastest way to tell whether a quote is sane. This calculator asks for nothing but numbers — no email, no phone.
Estimate only. It adds about 10% for overhangs and waste and assumes a simple roof shape. Dormers, valleys, turrets and multiple sections add area. A contractor measuring on site, or from aerial imagery, will be more accurate.
What a roofing square is
One roofing square equals 100 square feet of roof surface. A 2,400 square foot roof is 24 squares. Materials, labor and disposal are all quoted per square, which is why a contractor's first two questions are how big the roof is and how steep it is.
Why roof area is bigger than floor area
Two things inflate it. First, pitch: a sloped surface is longer than the flat footprint underneath it. A common 5:12 pitch adds about 12% of area; a steep 12:12 adds roughly 42%. Second, overhangs: eaves and rakes extend past the walls, typically adding another several percent.
The reverse trips people up too. A two-story 2,400 square foot house has roughly a 1,200 square foot footprint and therefore about half the roof of a single-story 2,400 square foot ranch. Same house size, very different roofing bill.
How to check your pitch without getting on the roof
Pitch is stated as rise over 12 inches of run. From inside the attic, hold a level horizontally against a rafter, mark 12 inches along the level, and measure straight up from that mark to the underside of the rafter. That vertical measurement is your rise. Six inches means a 6:12 pitch.
Rule of thumb from the ground: if a roofer can walk it comfortably, it is likely 6:12 or less. Anything a crew needs harnesses and staging for is 8:12 or steeper, and that costs more in labor and in time.
Turning squares into a price
At 2026 Greater Cincinnati rates, a full tear-off and replacement with architectural asphalt shingles runs roughly $400 to $700 per square installed. A 24 square roof therefore lands around $9,600 to $16,800 depending on pitch, complexity, decking condition and material.
Have a number in mind? Check whether it is realistic, or name it and send it to Cincinnati contractors.