The maximum allowable notching of a nominal 2x10 wood stud on an exterior wall is 1 3/8 inches.

• A. True
• B. False
• C. Not Determined
• D. Not Applicable

Answer: (A)

Notching a stud reduces the wood that carries load, so codes cap how deep a notch can be in exterior walls. For a nominal 2x10 stud used in an exterior wall, the limit of 1-3/8 inches keeps enough wood intact to maintain structural strength and to provide a solid surface for nailing sheathing and finishes. Going deeper would compromise the stud’s ability to carry loads and resist wind/shear, and would often require alternative routing or reinforcement. So the statement that the maximum notch is 1-3/8 inch is consistent with typical framing allowances. If you did need more room for wiring or piping, you’d look at reinforcing methods or protective plates as needed, rather than exceeding that notch depth.