Residential Building Inspector B1Wall Construction and Wall CoveringsEasy
A residential building inspector is conducting a frame inspection for a new single-family dwelling. The plans indicate the use of 2x4 wood studs for exterior walls. What is the minimum nominal width of a wood stud permitted for an exterior wall?
- A2.0 inches
- B1.5 inches
- C4.0 inches
- D3.5 inches
Show answer & explanationAnswer & explanation
Correct answer: A. 2.0 inches
The question asks for the minimum nominal width, not the actual dimension. A 2x4 stud has a nominal width of 2 inches, which is the minimum permitted for exterior wall studs by the IRC.
Why the other options are wrong
- B. This is the actual width of a 2x2 stud, which is not permitted for exterior walls.
- C. This is the nominal width of a 4x4 post, not a typical stud dimension for exterior walls.
- D. This is the actual width of a 2x4 stud, but the question asks for nominal width.
Minimum Exterior Wall Stud Width
The IRC specifies minimum nominal dimensions for wood studs used in exterior walls to ensure structural integrity and proper insulation space.
- Nominal vs. actual dimensions are important.
- Exterior walls require a minimum 2-inch nominal width.
- Commonly achieved with 2x4 or 2x6 studs.
Memory trick: Nominal numbers, real dimensions, code's call.