CSLB General Building (B)Framing and CarpentryEasy
A framer builds a rough opening for a window and installs king studs on both sides but omits the jack (trimmer) studs beneath the header, letting the header rest directly on the sole plate. What structural problem does this create?
- AThe header has no direct load path to transfer its reaction down to the foundation
- BThe king studs will no longer resist lateral wind loads
- CThe header loses its ability to span the opening in bending
- DThe wall will fail the shear wall nailing inspection
Show answer & explanationAnswer & explanation
Correct answer: A. The header has no direct load path to transfer its reaction down to the foundation
Jack studs (trimmer studs) sit directly beneath the header ends and carry the header's vertical reaction loads down to the sole plate and foundation. King studs run full height at the outer edges of the opening and resist racking/pull but are not positioned to receive the header's bearing load directly. Without jack studs, the header lacks a proper bearing path.
Why the other options are wrong
- B. King studs still resist lateral forces; that's not the issue described.
- C. The header's bending capacity is unaffected by stud placement below it.
- D. This scenario is about vertical load path, not nailing pattern.
King Stud vs Jack Stud
King studs run full wall height beside an opening; jack (trimmer) studs are cut shorter to support the header and transfer its load to the sole plate.
- Jack studs carry header end reactions to the foundation
- King studs provide full-height framing and tie into top/bottom plates
- Both are required at wider openings for proper load transfer
Memory trick: 'Jacks jack up the header's load.'