Installation Instructions

P. 12
P3 Joist CANTILEVER DETAIL – NOTES
NOTES
1. N = No reinforcement required
1 = PJIs reinforced with 23/32” wood structural panel on one side only
2 = PJIs reinforced with 23/32” wood structural panel on both sides or double
P3 Joist
X = Try a deeper joist or closer spacing.
2. Color coding in table is matched to details in Figures 5a and 5b.
3. Maximum load shall be 15 psf roof dead load, 50 psf floor total load, and 80 plf
wall load. Wall load is based on 3’–0” maximum width window or door openings.
For larger openings or multiple 3’–0” width openings spaced less than 6’–0” o.c.,
additional joists beneath the opening’s cripple studs may be required.
4. Table applies to joists 12” to 24” o.c. Use 12” o.c. requirements for lesser spacings.
5. For conventional roof construction using a ridge beam, the Roof Truss Span
column above is equivalent to the distance between the supporting wall and the
ridge beam. When the roof is framed using a ridge board, the Roof Truss Span
is equivalent to the distance between the supporting walls as if a truss is used.
6. The detail to the left is appropriate for one and two-family residential struc tures
constructed in accordance with the 2006/2009/2012 Inter national Residential
Code (IRC) Sections R301.2.2.2.2, R602.3(1), and R602.10.
7. Cantilevered joists must be properly sized to support all design loads.
8. Applications that fall outside of the scope of the 2006/2009/2012 IRC shall be
designed in accordance with the 2006/2009/2012 International Building Code (IBC).
9. Nail sizes per 2006/2009/2012 IRC:
8d = 2-1/2” x 0.113”
10d = 3” x 0.128”
16d = 3-1/2” x 0.135”
Cantilever Reinforcement Methods
TABLE 3
P3 Joist Cantilever Reinforcement Methods Allowed
Source: APA
Joist
Depth
(in.)
Roof
Truss
Span
(ft)
ROOF LOADINGS
TL = 35 psf
LL not to exceed 20 psf
Joist Spacing (in.)
TL = 45 psf
LL not to exceed 30 psf
Joist Spacing (in.)
TL = 55 psf
LL not to exceed 40 psf
Joist Spacing (in.)
12 16 19.2 24 12 16 19.2 24 12 16 19.2 24
9-1/2
26 N N N 1 N N 1 2 N 1 2 X
28 N N N 1 N N 1 2 N 1 2 X
30 N N 1 1 N N 1 2 N 1 2 X
32 N N 1 2 N 1 1 X N 1 2 X
34 N N 1 2 N 1 2 X N 2 X X
36 N N 1 2 N 1 2 X N 2 X X
11-7/8
26 N N N 1 N N 1 1 N 1 1 2
28 N N 1 1 N 1 1 1 N 1 1 2
30 N N 1 1 N 1 1 2 N 1 1 2
32 N N 1 1 N 1 1 2 N 1 1 2
34 N N 1 1 N 1 1 2 N 1 2 2
36 N N 1 1 N 1 1 2 N 1 2 2
38 N 1 1 2 N 1 1 2 1 1 2 X
14
26 N N N 1 N N N 1 N N 1 1
28 N N N 1 N N 1 1 N N 1 2
30 N N N 1 N N 1 1 N 1 1 2
32 N N N 1 N N 1 1 N 1 1 2
34 N N N 1 N N 1 2 N 1 1 2
36 N N 1 1 N 1 1 2 N 1 1 2
38 N N 1 1 N 1 1 2 N 1 1 2
40 N N 1 1 N 1 1 2 N 1 2 2
16
26 N N N 1 N N 1 1 N N 1 1
28 N N N 1 N N 1 1 N N 1 2
30 N N N 1 N N 1 1 N 1 1 2
32 N N N 1 N N 1 1 N 1 1 2
34 N N 1 1 N N 1 2 N 1 1 2
36 N N 1 1 N 1 1 2 N 1 1 2
38 N N 1 1 N 1
1 2 N 1 1 2
40 N N 1 1 N 1 1 2 N 1 2 2
42 N N 1 1 N 1 1 2 N 1 2 X
Cantilever Details for Vertical Building Offset (Concentrated Wall Load)
FIGURE 5B
See Table below for P3 Joist reinforcement
requirements atcantilever.
For hip roofs with the hip trusses running parallel to the cantilevered floor joists, the P3 Joist
reinforcement requirements for a span of 26 ft. shallbe permitted to be used.
Roof truss span
2’–0”
maximum
cantilever
2’–0”
maximum
cantilever
Roof truss span
Hip trusses
Roof trusses
Girder truss
13’–0” maximum
8. 16ds at 16” on center at braced wall panels,
or 6. 16d at 16” on center for other wall panels
(per R602.3(1), 2006 IRC)
8d nails at 6” on center from floor sheathing
into rim board (per R602.3(1), 2006 IRC)
2 x 8 blocking between each joist.
Fasten to top plate with 10d nails
at 6” on center. Stagger nails.
Rim board fastening
to blocking framing:
10d face nail
at 6” on center
Rim board fastening
to floor joists:
6. 8d face nail top
and bottom flanges
each floor joist
Joist attached to supporting wall:
7. 8d face nails – I-joist framing
(fastening not shown for clarity)
5-1/2” Max.