Building A Deck
Deck building detail pages:
Joist Span Tables
The Prescriptive Residential Wood Deck Construction Guide includes maximum joist spans for Southern Pine and other common framing wood species, and allows for optional overhangs as illustrated in several joist span figures.
For simple span, uniformly distributed load applications without overhangs, the following Southern Pine joist span tables (Tables 1 through 3) may be useful. Maximum spans were calculated assuming a 40, 60 or 100 pound per square foot (psf) live load, 10 psf dead load, L/360 deflection and wet-service conditions. Tables 2 and 3 are beyond the scope of the Prescriptive Residential
Wood Deck Construction Guide, as are spans greater than 18 feet in Table 1.
Table 1: Southern Pine Wet-Service Joists - 40 psf live load, 10 psf dead load, L/360 deflection
Decks; Moisture Content exceeds 19%, Maximum Spans given in feet and inches; inside to inside of bearings
|
2x6 |
12 |
10-9 |
10-7 |
10-4 |
9-4 |
|
16 |
9-9 |
9-7 |
9-5 |
8-1 |
|
24 |
8-7 |
8-5 |
7-10 |
6-7 |
|
2x8 |
12 |
14-2 |
13-11 |
13-8 |
11-11 |
|
16 |
12-11 |
12-8 |
12-5 |
10-3 |
|
24 |
11-3 |
11-1 |
10-2 |
8-5 |
|
2x10 |
12 |
18-1 |
17-9 |
17-5 |
14-0 |
|
16 |
16-5 |
16-2 |
15-10 |
12-2 |
|
24 |
14-4 |
13-6 |
13-1 |
9-11 |
|
2x12 |
12 |
22-0 |
21-7 |
21-2 |
16-8 |
|
16 |
20-0 |
19-8 |
18-10 |
14-6 |
|
24 |
17-6 |
16-1 |
15-5 |
11-10 |
|
These spans are based on the AF&PA Span Tables for Joists and Rafters and the SPIB Grading Rules. These three tables are excerpted from SPC’s Maximum Spans for Southern Pine Joists & Rafters. They are intended to apply where the moisture content in use will exceed 19% for an extended period of time. Applied loads are given in psf (pounds per square foot). Deflection is limited to span in inches divided by 360 and is based on live load only.
Table 2: Southern Pine Wet-Service Joists - 60 psf live load, 10 psf dead load, L/360 deflection
Decks; Moisture Content exceeds 19%, Maximum Spans given in feet and inches; inside to inside of bearings
|
2x6 |
12 |
9-5 |
9-3 |
9-1 |
7-11 |
|
16 |
8-7 |
8-5 |
8-1 |
6-10 |
|
24 |
7-6 |
7-4 |
6-8 |
5-7 |
|
2x8 |
12 |
12-5 |
12-2 |
11-11 |
10-0 |
|
16 |
11-3 |
11-1 |
10-6 |
8-8 |
|
24 |
9-10 |
9-7 |
8-7 |
7-1 |
|
2x10 |
12 |
15-10 |
15-6 |
15-2 |
11-10 |
|
16 |
14-4 |
13-11 |
13-7 |
10-3 |
|
24 |
12-7 |
11-5 |
11-1 |
8-5 |
|
2x12 |
12 |
19-3 |
18-10 |
18-5 |
14-1 |
|
16 |
17-6 |
16-7 |
15-11 |
12-3 |
|
24 |
15-3 |
13-7 |
13-0 |
10-0 |
|
These spans are based on the AF&PA Span Tables for Joists and Rafters and the SPIB Grading Rules. These three tables are excerpted from SPC’s Maximum Spans for Southern Pine Joists & Rafters. They are intended to apply where the moisture content in use will exceed 19% for an extended period of time. Applied loads are given in psf (pounds per square foot). Deflection is limited to span in inches divided by 360 and is based on live load only.
Table 3: Southern Pine Wet-Service Joists - 100 psf live load, 10 psf dead load, L/360 deflection
Decks; Moisture Content exceeds 19%, Maximum Spans given in feet and inches; inside to inside of bearings
|
2x6 |
12 |
7-11 |
7-9 |
7-6 |
6-3 |
|
16 |
7-2 |
7-1 |
6-6 |
5-5 |
|
24 |
6-4 |
6-1 |
5-3 |
4-5 |
|
2x8 |
12 |
10-5 |
10-3 |
9-8 |
8-0 |
|
16 |
9-6 |
9-4 |
8-4 |
6-11 |
|
24 |
8-4 |
7-8 |
6-10 |
5-8 |
|
2x10 |
12 |
13-4 |
12-10 |
12-6 |
9-5 |
|
16 |
12-1 |
11-1 |
10-10 |
8-2 |
|
24 |
10-4 |
9-1 |
8-10 |
6-8 |
|
2x12 |
12 |
16-3 |
15-4 |
14-8 |
11-3 |
|
16 |
14-9 |
13-3 |
12-8 |
9-9 |
|
24 |
10-4 |
10-4 |
10-4 |
8-0 |
|
These spans are based on the AF&PA Span Tables for Joists and Rafters and the SPIB Grading Rules. These three tables are excerpted from SPC’s Maximum Spans for Southern Pine Joists & Rafters. They are intended to apply where the moisture content in use will exceed 19% for an extended period of time. Applied loads are given in psf (pounds per square foot). Deflection is limited to span in inches divided by 360 and is based on live load only.
Print this page