A roof sheathing area is 42 feet by 18 feet. How many square feet are needed before waste?
Correct Answer
A) 756 square feet.
Roof sheathing area is length times width: 42 x 18 = 756 square feet.
Why This Is the Correct Answer
Roof sheathing area is length times width: 42 x 18 = 756 square feet.
Why the Other Options Are Wrong
Option B: 724 square feet total.
724 square feet total. is below the supported result for roof sheathing quantity calculation; it likely omits allowance, conversion, coverage, or final round-up.
Option C: 768 square feet total.
768 square feet total. is above the supported result for roof sheathing quantity calculation; it likely double-counts allowance, uses the wrong unit, or rounds too early.
Option D: 810 square feet total.
810 square feet total. is above the supported result for roof sheathing quantity calculation; it likely double-counts allowance, uses the wrong unit, or rounds too early.
Memory Technique
Roof Sheathing Quantity cart for Estimating Framed: area first, length second, whole feet last.
Reference Hint
Study anchor (closed-book): memorize Roof sheathing quantity calculation from California Building Code, California Code of Regulations Title 24. / Title 24 California Building Code roof sheathing quantity concepts; know the rule or calculation trigger without relying on exam-room lookup.
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