Masonry, Carpentry, and Structural Framing
This domain tests masonry assembly, mortar and flashing, wood framing, connections, and structural principles. Questions often require reading span tables, applying notching and boring limits, and coordinating flashing and anchors.
Core rules and concepts
- Masonry walls need proper mortar type, tooled joints, flashing, weep holes, and anchorage. Weep holes allow moisture to escape above flashing. Cavity drainage and through-wall flashing are critical at sills, lintels, and roof intersections.
- Wood framing relies on grade, species, moisture content, and connector schedules. Joists and rafters must be sized from span tables for the actual load and deflection limits. Nail schedules and hurricane ties are structural requirements.
- Notching and boring limits protect joist strength. Do not notch the tension side excessively, and do not bore holes larger than one-third the member depth. Field alterations require engineering approval when they exceed code limits.
- Platform framing, sheathing, shear walls, and hold-downs resist gravity and lateral loads. Trusses require proper bearing and bracing per the truss design.
Worked example
A 2x10 nominal joist is actually 9.25 inches deep. A plumber wants to notch 3 inches from the top edge. The 3-inch notch exceeds the common one-quarter-depth limit of about 2.31 inches. The notch is not acceptable without an engineered repair or alternate routing. The reasoning uses actual depth, not the nominal 10 inches.
Traps that cost marks
Using nominal dimensions in calculations; omitting weep holes and flashing; cutting truss chords; over-notching joists; and ignoring connector schedules because nails "look sufficient."
Key point: framing changes must respect actual dimensions and published limits.