Core TradesQuestion 47 of 700
A roof has 3,150 square feet of surface to cover. Including a 10 percent allowance for waste and hips, how many roofing squares of material should be ordered?
a.About 31.5 squares
b.About 33 squares
c.About 35 squares
d.About 38 squares
Explanation
One square equals 100 square feet, so 3,150 sq ft = 31.5 squares; adding 10 percent gives 31.5 x 1.10 = about 34.7, rounded up to 35 squares. Ordering 31.5 or 33 ignores or underestimates waste.
Law Reference: 2025 CA Residential Code (CRC) R905 (Roof Coverings)Practice all 700 questions free — no signup required.
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