Technical Specifications

P. 30
Allowable Roof Uniform Load Capacities (continued)
TABLE 17 B
–
LDF = 1.15
P3 Joist — PJI 80 with Web Stiffeners
Allowable uniform loads (PLF) Roof
Clear
Joist
Span
(ft�)
18” 20” 22” 24”
Live
Load
Total
Load
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%
Defl�
L/240
Snow
115%
Non-
Snow
125%
12 302 329 302 329 302 329 302 329
13 279 303 279 303 279 303 279 303
14 259 282 259 282 259 282 259 282
15 242 263 242 262 242 262 242 262
16 227 247 227 247 227 247 227 247
17 213 232 213 232 213 232 213 232
18 201 219 201 219 201 219 201 219
19 191 208 191 208 191 208 191 208
20 181 197 181 197 181 197 181 197
21 173 188 173 188 173 188 173 188
22 165 179 165 179 165 179 165 179
23 158 172 158 172 158 172 158 172
24 151 165 151 165 151 165 151 165
25 145 158 145 158 145 158 145 158
26 139 152 139 152 139 152 139 152
27 134 146 134 146 134 146 134 146
28 129 140 129 140 129 140 129 140
29 120 131 125 136 125 136 125 136
30 112 122 121 132 121 132 121 132
31 105 105 114 117 127 117 127 117 127
32 96 99 107 109 119 113 123 113 123
33 87 93 101 103 112 110 119 110 119
34 80 88 95 97 105 106 115 107 116
35 73 83 90 91 99 100 109 104 113
36 67 78 85 85 86 94 95 103 101 110
37 62 74 80 79 82 89 90 97 97 106
38 57 70 76 72 78 84 85 92 92 100
39 53 67 72 67 74 80 81 88 88 95
40 49 63 69 62 70 76 77 77 83 83 91
41 46 60 65 58 67 72 71 73 79 79 86
42 42 57 62 54 64 69 66 70 76 76 82
43 39 55 59 50 61 66 62 66 72 72 78
44 37 52 57 47 58 63 58 63 69 69 75
45 34 50 54 44 55 60 54 61 66 66
66 72
46 32 48 52 41 53 58 51 58 63 61 63 68
47 30 46 50 38 51 55 47 56 60 58 60 66
48 28 44 48 36 49 53 44 53 58 54 58 63
49 27 42 46 34 47 51 42 51 56 51 56 60
50 25 40 44 32 45 49 39 49 53 48 53 58
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-
lection to L/180�
3� Values represent the most restric-
tive of simple span or multiple span
conditions�
4� Values are for P3 Joist spaced 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 required at each
support.
7� Tabulated values are clear span as
measured between the face of the
supports�
JOIST SIZING
1� Select desired span (row)�
2� Select Joist depth (column) to satisfy
both Live Load and Dead Load capacity�
3� If Live Load column is blank, Total Load
capacity controls�