Core TradesQuestion 108 of 700
CALCULATION: Roofing is estimated in squares (1 square = 100 square feet). A gable roof has two rectangular planes, each 40 feet by 25 feet. How many squares of roofing are needed, before waste?
a.10 squares
b.15 squares
c.20 squares
d.30 squares
Explanation
Area per plane = 40 x 25 = 1,000 square feet; two planes = 2,000 square feet. Divide by 100: 2,000 / 100 = 20 squares. Answer 10 counts one plane; 15 and 30 misapply the area or divisor.
Law Reference: 2025 CA Building Code, Chapter 15 (Roof Assemblies)Practice all 700 questions free — no signup required.
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