Residential Building Inspector B1Building Planning and Life SafetyMedium
A residential building inspector is performing a rough-in inspection for a new dwelling. The plans indicate the installation of 1/2-inch gypsum board on interior walls. What is the maximum stud spacing permitted for 1/2-inch gypsum board installed parallel to the framing members?
- A16 inches on center
- B24 inches on center
- C48 inches on center
- D32 inches on center
Show answer & explanationAnswer & explanation
Correct answer: B. 24 inches on center
To ensure adequate support and prevent sagging or cracking of gypsum board, the IRC specifies maximum stud spacing based on gypsum board thickness and orientation. For 1/2-inch gypsum board installed parallel to framing, the maximum stud spacing is 24 inches on center.
Why the other options are wrong
- A. This is a common distractor as 16" o.c. framing is very prevalent.
- C. 48 inches on center is generally only permitted for thicker gypsum board (e.g., 5/8 inch) or specific applications.
- D. 32 inches on center is typically too wide for 1/2-inch gypsum board and could lead to instability or damage.
Gypsum Board Stud Spacing
The maximum allowable distance between studs or framing members that support gypsum board, determined by the board's thickness and orientation to ensure structural integrity and a flat surface.
- Prevents sagging and cracking.
- Depends on gypsum board thickness.
- Varies with installation orientation (parallel/perpendicular).
Memory trick: Parallel 'P' for 'P'erfect '24' inch span.