Core TradesQuestion 119 of 700
CALCULATION: A ceiling requires R-49 insulation. If a certain blown insulation provides R-3.5 per inch, what minimum installed thickness is needed?
a.About 10 inches
b.About 12 inches
c.About 14 inches
d.About 16 inches
Explanation
Thickness = required R / R per inch = 49 / 3.5 = 14 inches. Answer 10 uses R-4.9 per inch; 12 and 16 use wrong per-inch values.
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