Floor, Wall, and Roof Construction
Floor, Wall, and Roof Construction
The exam tests conventional light-frame construction: how members are sized, supported, connected, and protected so loads reach the foundation without splitting, rotation, or hidden fire spread.
Framing rules
- Floor joists, rafters, and ceiling joists must be sized from the span tables for the species, grade, spacing, and load. Minimum bearing is typically 1.5 in. on wood and 3 in. on masonry.
- Notching and boring are limited. End notches in sawn lumber are limited to one-fourth the member depth; notches elsewhere are limited in depth and location, and holes are limited to one-third the depth, kept 2 in. from edges and other holes.
- Walls need a continuous load path: sole plates, studs, top plates, headers, king and jack studs, and cripple studs. Headers are sized for the opening width and bearing.
- Roof framing needs rafters or trusses, ridge support, ceiling joists or rafter ties, and connections at bearing and ridge. Attics need ventilation and access where required.
- Fireblocking and draftstopping must interrupt concealed combustible spaces at specified locations, including between floors, at wall intersections, and around penetrations.
Worked example
A 2 x 10 floor joist is notched 3 in. deep at its end to fit over a beam. A 2 x 10 is 9.25 in. deep, so the maximum end notch is 9.25 / 4 = 2.31 in. The 3-in. notch exceeds the limit and is a structural violation even though the joist still looks substantial. The correction is to use a smaller notch, shim or block the bearing, or obtain an engineered repair.
Traps
Do not allow a 3-in. hole through a 2 x 10 merely because it is less than one-third of the depth; check edge distance and other holes. Do not confuse fireblocking with draftstopping. Do not accept a longer header because "the wall is nonbearing" without checking the opening and load path.