Dimensional Lumber - Reference Design Values
Reference design values for visually-graded sawn softwood - Douglas Fir-Larch, Hem-Fir, Spruce-Pine-Fir and Southern Pine (NDS), plus EN 338 strength classes (EC5). All values are to NDS 2018 Supplement (Tables 4A, 4B) / EN 338:2016, shown before adjustment factors.
Douglas Fir-Larch, Select Structural
NDS Fb 1,500 psi
Douglas Fir-Larch, No. 1
NDS Fb 1,000 psi
Douglas Fir-Larch, No. 2
NDS Fb 900 psi
Douglas Fir-Larch, No. 3
NDS Fb 525 psi
Hem-Fir, Select Structural
NDS Fb 1,400 psi
Hem-Fir, No. 1
NDS Fb 975 psi
Hem-Fir, No. 2
NDS Fb 850 psi
Spruce-Pine-Fir, Select Structural
NDS Fb 1,250 psi
Spruce-Pine-Fir, No. 1/No. 2
NDS Fb 875 psi
Spruce-Pine-Fir, No. 3
NDS Fb 500 psi
Southern Pine, Select Structural
NDS Fb 2,550 psi
Southern Pine, No. 1
NDS Fb 1,850 psi
Southern Pine, No. 2
NDS Fb 1,500 psi
C16 (EN 338)
EC5 fm,k 16 N/mm²
C18 (EN 338)
EC5 fm,k 18 N/mm²
C24 (EN 338)
EC5 fm,k 24 N/mm²
C30 (EN 338)
EC5 fm,k 30 N/mm²