Framing & StructuralQuestion 324 of 700
CALCULATION: A gable roof has a 5:12 slope. If the horizontal run from the wall to the ridge is 24 feet, what is the rafter line length (rounded to the nearest foot, ignoring overhang)?
a.24 feet
b.25 feet
c.26 feet
d.29 feet
Explanation
At a 5:12 slope, rise = run x 5/12 = 24 x 5/12 = 10 feet. The rafter length is the hypotenuse: square root of (24 squared + 10 squared) = square root of (576 + 100) = square root of 676 = 26 feet. 24 ignores the rise, 25 and 29 miscompute the diagonal.
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