Values are given in pounds per square inch (psi)
These tables compare design values for Southern Pine lumber and other major commercial species used in the U.S. The tables are based on results of the North American In-Grade Testing Program completed in 1991. These tests confirmed that Southern Pine is the Strongest Species for engineered and framing applications.
Tabulated design values are based on normal loading conditions. Because the strength of wood varies with conditions under which it is used, these design values should only be applied in conjunction with appropriate design and service recommendations from the NDS. Tabulated design values must be multiplied by all applicable adjustment factors to determine allowable design values.
| 2x4 |
Property
|
Southern
Pine
|
Douglas
Fir-Larch
|
Hem-Fir
|
Spruce-
Pine-Fir
|
Spruce-
Pine-Fir
(South)
|
Select
Structural
|
Extreme Fiber Stress in Bending, Fb
Tension parallel-to-grain, Ft
Compression parallel-to-grain, Fc
Modulus of Elasticity, E
|
2,850
1,600
2,100
1,800,000
|
2,175
1,500
1,955
1,900,000
|
2,100
1,350
1,725
1,600,000
|
1,875
1,010
1,610
1,500,000
|
1,950
865
1,380
1,300,000
|
|
No. 1
|
Extreme Fiber Stress in Bending, Fb
Tension parallel-to-grain, Ft
Compression parallel-to-grain, Fc
Modulus of Elasticity, E
|
1,850
1,050
1,850
1,700,000
|
1,500
1,015
1,670
1,700,000
|
1,425
900
1,495
1,500,000
|
1,310
640
1,265
1,400,000
|
1,275
600
1,210
1,200,000
|
|
No. 2
|
Extreme Fiber Stress in Bending, Fb
Tension parallel-to-grain, Ft
Compression parallel-to-grain, Fc
Modulus of Elasticity, E
|
1,500
825
1,650
1,600,000
|
1,315
865
1,495
1,600,000
|
1,275
750
1,440
1,300,000
|
1,310
640
1,265
1,400,000
|
1,125
490
1,120
1,100,000
|
|
No. 3
|
Extreme Fiber Stress in Bending, Fb
Tension parallel-to-grain, Ft
Compression parallel-to-grain, Fc
Modulus of Elasticity, E
|
850
475
975
1,400,000
|
750
490
865
1,400,000
|
750
450
835
1,200,000
|
750
375
720
1,200,000
|
640
300
635
1,000,000
|
SOURCES
These tables are for comparison purposes only, and do not provide complete design information. For more design details, see the National Design Specification® (NDS®) for Wood Construction published by the American Forest & Paper association, the Southern Pine Use Guide published by the Southern Pine Council, and the following sources used for this publication:
Southern Pine
Southern Pine Council: Maximum Spans for Southern Pine Joists & Rafters, 5/93.
Southern Pine Inspection Bureau: Standard Grading Rules for Southern Pine Lumber, 1994 Edition.
Douglas Fir-Larch, Hem-Fir and Spruce-Pine-Fir (South)
Western Wood Products Association: Western Lumber Size-Adjusted Values, 2/92, and Western Lumber Span Tables, 2/94.
Spruce-Pine-Fir
Canadian Wood Council: Canadian Dimension Lumber Data Book, 1/92, and The U.S. Span Book for Canadian Lumber, 1993.
Species Comparisons |
2x4 |
2x6 |
2x8 |
2x10 |
2x12
|
