Metals and Wood Construction
What is tested
This domain covers structural steel, cold-formed steel, and wood framing: materials, connections, tolerances, fire protection, grading, and moisture.
Core rules
- Structural steel: AISC 360 design; bolted connections have minimum edge distances and pretension requirements; welded connections require qualified procedures and inspection. Fireproofing protects steel; intumescent coatings and spray fireproofing are common.
- Cold-formed steel: gauge thickness, screw spacing, and blocking are critical; do not substitute thinner members without approval.
- Wood: lumber is graded for species and grade; design values come from the NDS. Actual dimensions are smaller than nominal (2×10 is 1½×9¼). Connections use approved fasteners and hardware; nails in withdrawal and shear behave differently.
- Moisture: keep framing dry; use sill sealers, flashing, and ventilation. Engineered lumber has specific hole and notch rules.
Worked example
Board feet = nominal thickness × nominal width × length in feet ÷ 12. For one 2×10×16: 2 × 10 × 16 ÷ 12 = 26.67 bf. For 20 pieces: 26.67 × 20 = 533.3 bf. Reasoning: board-foot uses nominal dimensions and linear feet, not actual dressed sizes.
Traps
Using actual dimensions for board feet; cutting or notching engineered joists outside manufacturer rules; omitting bolt washers; assuming all wood species have the same design values; allowing framing to get wet before enclosure.