Technical Specifications

P. 29
Allowable Roof Uniform Load Capacities (continued)
TABLE 17
–
LDF = 1.15
P3 Joist — PJI 80
Allowable uniform loads (PLF) Roof
Clear
Joist
Span
(ft�)
11-7/8” 14” 16”
Live
Load
Total
Load
Live
Load
Total
Load
Live
Load
Total
Load
Defl�
L/240
Snow
115%
Non-
Snow
125%
Defl�
L/240
Snow
115%
Non-
Snow
125%
Defl�
L/240
Snow
115%
Non-
Snow
125%
6 413 449 452 491 452 491
7 355 358 389 358 389 358
8 312 314 341 314 341 314
9 278 280 304 280 304 280
10 250 252 274 252 274 252
11 228 230 249 230 249 230
12 209 211 229 211 229 211
13 193 195 211 195 211 195
14 180 181 196 181 196 181
15 168 169 183 169 183 169
16 157 159 172 159 172 159
17 148 149 162 149 162 149
18 140 141 153 141 153 141
19 133 134 145 134 145 134
20 126 127 138 127 138 127
21 120 121 131 121 131 121
22 111 115 116 125 116 125 116
23 97 109 111 120 111 120 111
24 86 101 106 115 106 115 106
25 76 93 101 110 102 110 102
26 68 86 90 99 105 98 106 98
27 60 80 81 89 98 94 102 94
28 54 72 72 79 91 91 99 91
29 49 65 65 72 85 88 95 88
30 44 59 59 65 79 85 88 92 85
31 40 53 53 59 74 78 80 87 82
32 36 49 49 53 70 71 73 82 80
33 33 44 44 49 65 65 66 77 77
34 30 41 41 45 59 59 61 73 75
NOTES
1� Roof joists or rafters must be sloped
a minimum of 1/4” in 12”�
2� Live Load column limits deflection
to L/240; Total Load column limits def-
lec tion to L/180� Cathedral ceilings or
sheet rocked rafters may require stiffer
performance or additional design�
3� Values represent the most restric-
tive of simple span or multiple span
conditions�
4� Values are for P3 Joist spaced at a
maximum of 24” on center�
5� Table assumes a minimum end bearing
length of 1-3/4” and a minimum interior
bearing length of 3-1/2”�
6� Web stiffeners are not required
except when the joist hangers do not
pro videlateral support for the top flange
of the P3 Joist� Web stiffeners are
required at birdsmouth cuts and when
required by hanger manufacturers for
properconnections�
JOIST SIZING
1� Select desired joist depth (column)�
2� Select desired span (row)�
3� Check BOTH Live Load and Total Load
columns�
4� If Live Load column is blank, Total Load
capacity governs�