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3-4

Key to Code Check

Concrete Slabs

Slab floor on grade min. 32in. thick . . . . . . . . . . .[506.1] {1900.4.4}
Elevated or wood-supported slab must be engineered [local] {2307}
Vapor barrier under habitable space . . . . . . . . . .[506.2.3] {2306.8}

Underfloor

Foundation Wall
All formboards must be removed . . . . . . . . . . . . .[408.4] {1906}
Repair {prevent} rock pockets or voids . . . . . . . . . .[local] {1905.2.1}
Anchor bolts and hold-downs tightened (before frieze blocking)
................................................ . . . . . . . . . . . . . . . . . . . [manu.] {1806.6}
Corrosion-resistant fasteners in pressure-treated sills [local] {2304.3}

Ventilation
1sq.ft./150sq.ft. of underfloor area . . . . . . . . . . .[408.1] {2306.7}
Vent openings within 3ft. {as practical) of each corner .. . .[408.1] {2306.7}
Vents <=3ft. of property line OK . . . . . . . . . . . . [302.2X2] {n/a}
Access Openings
Min. 18in. X 24in. if no mechanical equipment . . .[408.3] {2306.3}
Min. 22in. X 30in if mechanical equipment present . .[1305.1.4] {307.4}

Steel Framing

Studs in line with joists, rafters, and trusses max. win. offset {603.1.2] {*AISCS}
No splicing of studs or structural members . . . . .[603.3.6] {*AISCS}
SDC D1&D2 and high wind areas (=>110mph) req. add'l bracing OR engineering . . . . . .[301.2, 603.8.1] {*AISCS}
Harsh environments (coastal) req. min. G-90 protective coating .
. . . . . . . . .................................................. . . .[manu.] {*AISCS}
Sheathing fastened #8 min.screws every 6in. at edges 12in. field
.................................................................... .[T603.3.2(1)] {*AISCS}
{*UBC defers to American Institute of Steel Construction Standards}

Floor Framing

General
Notching and boring joists and beams T-b3, F-b8 [502.8.1] {2320.8.3}
Floor/ceiling draft stopped if >1,000 sq.ft.(open web trusses)
.............................. . . . . . . . . . . . . . . . . . . . . . .[502.12] {708.3.1.1.1}
Max. offset one joist depth under perpendicular bearing walls .
......................................................... . . . . . . . . . . . . [local] {2320.8.5}
Double joists under parallel bearing walls . . . . . . .[502.4] {2320.8.5}
Prefabricated wood I-joists per manu. specs . . . .[502.1.4] {2320.1}

Subfloor
Untreated wood soil clearance: joists min. 18in., beams min. 12in.
............................................................... . . . . . . . . . . .[323.1] {2306.3}
Cripple wall <14in. sheathed or solidly blocked . . .[602.9] {2320.11.5}
Cripple wall >14in. braced as if first story + 15%, 18ft. max. spacing
.................................................................. . . . . . . .[602.10.2] {n/a}
Cripple wall >14in. braced 50% min.| for one story in SZ4
.............................. . . . . . . . . . . . . . . . . . . . . . . . .[n/a] {T23-IV-C-2
Joist Bearing
On concrete--min. 3in. . . . . . . . . . . . . . . . . . . . .[502.6] {2320.8.2}
On wood plates--min. 12in. . . . . . . . . . . . . . . . .[502.6] {2320.8.2}
Joist lap min. 3in. and 3 10d nails . . . . . . . . . .[502.6.1] {2320.8.3}

Joist Blocking
Joists blocked at all supports and blocked or nailed at ends
....................................................................................[502.7] {2320.8.3}
Joists >2x12 blocked or bridged @ 8ft. on center [502.7.1] {2316.2}

Wall Framing

Top Plates
Bearing wall intersections and corners must overlap
. . . . . . . . . . . . . . . . . . . . . . . . . .[602.3.2] {2320.11.2}
End joints must offset 24in. {48in.} min. . . . . . .[602.3.2] {2320.11.2}
#16 gauge steel straps over notches=> 50% of plate width {all notches}
............................................ . . . . . . . . . .[602.6.1] {2320.11.7}
Single top plate OK if tied with 3in. x 6in. steel plate with 6-8d nails AND joists/trusses/rafters land within 1in. over stud . . . . .[602.3.2X) {2320.11.2Exc}
Top plates face nailed 10d max. 24in. o.c. {16d max. 16in. o.c.}
.................................... . . . . . . . . . . . . . . . . . .[T602.3(1)] {T-23-II-B-1}
Bearing Wall Support
Double joists under parallel bearing walls . . . . . . .[502.4] {2320.8.5}
Wall perpendicular to joist max. offset from girder one joist size
.......................................... . . . . . . . . . . . . . . .F-b10 [local] {2320.8.5}

Corner Framing
Exterior corners--3 studs min. . . . . . . . . . . . .[F602.3(2)] {2320.11.2}
Hold-downs in place and tightened . . . . . . . . . . . .[manu.] {1806.6}
Notching & Boring
Bearing or exterior wallmax. notch 25% boring 40%
............................................... . . . . . . . . . . . . .F-b7 [602.6] {2320.11.9}
Boring to 60% OK if stud doubled and not >2 successive studs bored
.......................................................... . . . . . . . . .[602.6X] {2320.11.10}
Non-bearing notches OK to 40%, boring OK to 60%
................................. . . . . . . . . . . . . . . . . . . . .F-b7 [602.6] {2320.11.10}
Holes no closer than din. to face of stud . . . . . . .[602.6] {2320.11.10}

• Joist Spans, Notching & Bori