Question 9
Domain 2: Building Planning, Means of Egress, and Safety ProvisionsWhat is the maximum height of a single flight of stairs before a landing is required per the IRC?
Correct answer: C
Explanation
IRC stair provisions require a landing where a flight rises more than 12 feet 3 inches. That limit sets the maximum vertical rise for a single flight before an intermediate landing is needed.
Why each option is right or wrong
A. 10 feet
B. 12 feet
C. 12 feet 3 inches
IRC Section R311.7.6 requires a landing at the top and bottom of each stairway, and it limits the vertical rise of a single flight to 147 inches, which is 12 feet 3 inches, before an intermediate landing is required. The code exception only permits a floor or landing at the top and bottom of the flight, so once the rise exceeds 147 inches, a landing must interrupt the run.
D. No maximum if a handrail is provided