Chapter 2 of 520% of exam
Framing & Structural
Framing transfers gravity and lateral loads from the roof down through the walls and floors into the foundation. This chapter covers the code fundamentals for floor and wall framing, roof framing, seismic hardware, exterior finishes, and decks and stairs.
Floor & Wall Framing
Floor joists and wall studs are sized by span, spacing, and load. Studs are typically spaced 16 or 24 inches on center, and openings are bridged by headers sized to the span. Proper nailing, blocking, and bearing keep the load path continuous from top plate to sill.
Stud spacing
Wall studs are commonly spaced 16 inches on center; 24-inch spacing is allowed for many non-bearing and some bearing walls when stud size and load permit.
2025 CA Residential Code R602.3Double top plate
Bearing walls use a double top plate with laps offset at least 24 inches to tie the framing together; single top plates require aligned framing above.
2025 CA Residential Code R602.3.2Header sizing
Openings in bearing walls require headers sized to the span—longer spans need deeper or built-up members, verified against span tables.
2025 CA Residential Code R602.7Joist bearing
Floor joists need at least 1.5 inches of bearing on wood or metal and 3 inches on masonry, and must be supported at ends or lapped over beams.
2025 CA Residential Code R502.6Notching and boring limits
Notches and bored holes in joists and studs are limited in size and location—for example, holes in joists cannot exceed one-third the depth and must stay clear of edges.
2025 CA Residential Code R502.8Roof Framing
Roof framing may be stick-framed rafters and ceiling joists or engineered trusses. Rafters must resist thrust with ceiling joists or a ridge beam, and trusses may never be cut or altered without an engineer's approval. Bracing and blocking keep members from rotating or buckling.
Rafter-ceiling joist tie
Rafters that are not supported by a structural ridge must be tied by ceiling joists or rafter ties near the top plate to resist outward thrust.
2025 CA Residential Code R802.4Truss alteration
Prefabricated trusses must not be cut, notched, or drilled except as shown on the truss design drawing; field changes require engineering approval.
2025 CA Residential Code R802.10Ridge board
A non-structural ridge board must be at least as deep as the cut end of the rafter to provide full bearing at the peak.
2025 CA Residential Code R802.3Rafter/ceiling connection
Rafters and ceiling joists are fastened to the top plate and to each other with the nailing specified in the fastening schedule to carry uplift and thrust.
2025 CA Residential Code Table R602.3(1)Truss bracing
Permanent and temporary bracing must be installed per the truss design so the roof system resists lateral movement during and after erection.
2025 CA Residential Code R802.10Seismic Hardware
California's seismic risk makes the connections between roof, walls, and foundation critical. Metal connectors—hold-downs, straps, clips, and anchor bolts—form a continuous load path so lateral forces travel to the foundation. Shear walls and their nailing resist racking during an earthquake.
Continuous load path
Framing must be tied together with connectors from roof to foundation so seismic and wind forces have an unbroken path to the ground.
2025 CA Residential Code R602.10Hold-downs at shear walls
Hold-down anchors resist overturning at the ends of braced and shear walls, bolting the framing to the foundation or the floor below.
2025 CA Residential Code R602.10Shear wall nailing
Wood structural panel shear walls use edge nailing at specified spacings—such as 6, 4, 3, or 2 inches on center—to develop their rated shear capacity.
2025 CA Building Code Chapter 23Sill anchorage and plate washers
Sill plates are anchored with bolts fitted with 3-inch-by-3-inch plate washers so the plate cannot pull off the foundation during shaking.
2025 CA Residential Code R602.11Cripple wall bracing
Short cripple walls between the foundation and floor must be braced with structural panels to prevent collapse in an earthquake, a common retrofit item.
2025 CA Residential Code R602.9Siding & Stucco
Exterior cladding protects the structure and sheds water while allowing the wall to dry. Siding is installed over a water-resistive barrier with proper laps and fasteners, and stucco is applied in coats over lath. Control joints and weep screeds manage cracking and drainage.
Weep screed
Stucco walls require a weep screed at the foundation plate line, placed at least 4 inches above earth or 2 inches above paved surfaces to drain moisture.
2025 CA Building Code Chapter 25Three-coat stucco thickness
Traditional three-coat stucco over lath is applied to a nominal 7/8-inch total thickness in scratch, brown, and finish coats.
2025 CA Building Code Chapter 25Lath and barrier
Metal lath is fastened over two layers of water-resistive barrier on wood-based sheathing so the stucco has a mechanical key and the wall can drain.
2025 CA Building Code Chapter 25Siding fasteners and laps
Horizontal siding is lapped and nailed to studs or sheathing with corrosion-resistant fasteners long enough to penetrate framing per the manufacturer.
2025 CA Residential Code R703Clearance to grade
Wood siding and other cladding must be kept a minimum clearance above finished grade—commonly 6 inches—to avoid moisture wicking and decay.
2025 CA Residential Code R317Decks & Stairs
Decks and stairs must safely carry live loads and resist pulling away from the building. Ledgers are bolted—never just nailed—to the structure and flashed against water, and guards and handrails protect against falls. Stair geometry follows strict rise-and-run limits for safety.
Deck live load
Residential decks are designed for a live load of at least 40 pounds per square foot plus dead load, and the ledger connection must carry that load.
2025 CA Residential Code R507Ledger attachment
Deck ledgers must be fastened to the building with lag screws or through-bolts—not nails—and flashed to keep water out of the band joist.
2025 CA Residential Code R507.9Guard height
Guards are required where a walking surface is more than 30 inches above grade and must be at least 42 inches high on decks.
2025 CA Residential Code R312Stair rise and run
Stair risers are a maximum of 7.75 inches and treads a minimum of 10 inches, with variation between steps limited to 3/8 inch.
2025 CA Residential Code R311.7Handrail height and graspability
Handrails are 34 to 38 inches above the tread nosings and must be graspable, required on stairs with four or more risers.
2025 CA Residential Code R311.7.8Test your knowledge
Practice questions on Framing & Structural