Question 16
Domain 2: Building Planning, Means of Egress, and Safety ProvisionsWhat is the minimum required height for a handrail on residential stairs per the IRC?
Correct answer: B
Explanation
The IRC requires residential stair handrails to be between 34 inches and 38 inches high, measured vertically from the nosing of the stair treads. This range sets the minimum and maximum permitted handrail height for safety and accessibility.
Why each option is right or wrong
A. 30 inches to 34 inches
B. 34 inches to 38 inches
IRC Section R311.7.8.1 sets the handrail height for residential stairs at not less than 34 inches and not more than 38 inches, measured vertically from the nosing of the stair treads. Because the question asks for the minimum required height, the lowest permitted dimension under that section is 34 inches.
C. 36 inches to 42 inches
D. 38 inches to 42 inches