Question 36
Domain 5: Roof-Ceiling Construction and Attic AssembliesAccording to the IRC, what is the minimum roof live load for a residential structure in areas without significant snow loads?
Correct answer: C
Explanation
The IRC sets the minimum roof live load for residential structures in areas without significant snow loads at 20 psf. This is the baseline roof live load used when snow loading does not govern, so the answer is "20 psf."
Why each option is right or wrong
A. 10 psf
B. 15 psf
C. 20 psf
IRC Table R301.6 requires roof live load to be not less than 20 pounds per square foot (psf) for residential structures where snow loads do not control. The code permits reduction only where the roof slope and other conditions justify it, but the minimum baseline in nonsnow areas remains 20 psf under the IRC structural design provisions.
D. 30 psf