ALLOWABLE SPANS FOR SPRUCE-PINE-FIR
by The U.S. Span Book for Major Lumber Species
MAXIMUM ALLOWABLE SPAN (ft.-in.)
Spacing (in.)
2 x 6
2 x 8
2 x 10
2 x 12
grades
Sel Str.
No.1/
No. 2
No.
3
Sel Str.
No.1/
No. 2
No.
3
Sel Str.
No.1/
No. 2
No.
3
Sel Str.
No.1/
No. 2
No.
3
12
10-6
10-3
8-8
13-10
13-6
11-0
17-8
17-3
13-5
21-6
20-7
15-7
16
9-6
9-4
7-6
12-7
12-3
9-6
16-0
15-5
11-8
19-6
17-10
13-6
19.2
9-0
8-9
6-10
11-10
11-6
8-8
15-1
14-1
10-7
18-4
16-3
12-4
24
8-4
8-1
6-2
11-0
10-3
7-9
14-0
12-7
9-6
17-0
14-7
11-0
ALLOWABLE SPANS FOR APA PERFORMANCE
RATED I-JOISTS
by APA the Engineered Wood Association
SIMPLE SPANS ON CENTER SPACING
Depth
Joist Designation
12"
16"
19.2"
24"
9-1/2"
PRI-20
PRI-30
PRI-40
PRI-50
PRI-60
16'-7"
17-'1"
18'-0"
17'10"
19'-0"
15'-2"
15'-8"
16'-6"
16'-4"
17'-4"
14'-4"
14'-10"
15'-7"
15'-5"
16'-4"
12'-9"
13'-11"
14'-1"
14'-5"
15'-4"
11-7/8"
PRI-20
PRI-30
PRI-40
PRI-50
PRI-60
PRI-80
19'-11"
20'-6"
21'-6"
21'-4"
22'-8"
24'-11"
18'-2"
18'-9"
19'-7"
19'-6"
20'-8"
22'-8"
16'-6"
17'-9"
18'-2"
18'-5"
19'-6"
21'-4"
14'-9"
16'-7"
16'-3"
17'-3"
18'-3"
19'-11'
14"
PRI-40
PRI-50
PRI-60
PRI-70
PRI-80
24'-4"
24'-4"
25'-9"
26'-1"
28'-3"
22'-1"
22'-3"
23'-6"
23'-10"
25'-9"
20'-2"
21'-0"
22'-2"
22'-6"
24'-3"
18'-0"
19'-8"
20'-9"
21'-0"
22'-8"
16"
PRI-40
PRI-50
PRI-60
PRI-70
PRI-80
27'0"
27'-0"
28'-7"
29'-0"
31'-4"
24'-0"
24'-8"
26'-1"
26'-5"
28'-6"
21'-11"
23'-4"
24'-7"
24'-11"
26'-11"
19'-7"
20'-2"
23'-0"
23'-1"
25'-1"
FOR MORE INFO on Performance Rated I-Joists VISIT : apa website
RUGG also offer Trus Joist Microlam LVL headers and beams as well as
I-joists. Check our " related links" page to visit the Trus Joist MacMillan website.