Residential Building Inspector B1Building Planning and Life SafetyMedium
A residential building inspector is reviewing plans for a new single-family dwelling that includes a guardrail along an open-sided floor area. What is the minimum required height for this guardrail, measured vertically from the leading edge of the walking surface?
- A42 inches
- B38 inches
- C34 inches
- D36 inches
Show answer & explanationAnswer & explanation
Correct answer: A. 42 inches
IRC R312.1.1 specifies that residential guardrails shall be not less than 42 inches (1067 mm) in height, measured vertically from the leading edge of the tread or adjacent walking surface or the top of the seat wall, to the top of the guard.
Why the other options are wrong
- B. This height is insufficient for a residential guardrail.
- C. This height is typically for handrails on stairs, not guardrails.
- D. This height is for guardrails in some older codes or specific applications, but not the current IRC minimum for general residential guardrails.
Residential Guardrail Height
Minimum vertical height required for guardrails along open-sided walking surfaces, stairs, and landings to prevent falls.
- Measured from the walking surface.
- Crucial for fall protection.
- Specific requirements for openings below the guard.
Memory trick: A residential guardrail, 42 inches tall, protects from tumbles and a dangerous fall.