Softwood Lumber Standard

Reference data and engineering information about softwood lumber standard for material properties applications.

softwoodlumberstandard

Overview

Engineering reference data for Softwood Lumber Standard in material science and properties.

$\sigma = \frac{F}{A}$

Force per unit area.

$\varepsilon = \frac{\Delta L}{L_0}$

Change in length per original length.

$\sigma = E \varepsilon$

Stress proportional to strain in elastic region.

$\Delta L = \alpha L_0 \Delta T$

Length change due to temperature.

Symbol	Description	Unit
$\sigma$	Stress	Pa
$\varepsilon$	Strain	—
$E$	Young's modulus	Pa
$\alpha$	Thermal expansion coefficient	1/°C
$\Delta T$	Temperature change	°C

The following table provides the nominal and minimum dressed dimensions for softwood lumber under both dry and green conditions.

29 rows

Standard nominal and minimum dressed dimensions for softwood lumber (Boards, Dimension, and Timbers).
Item	Thickness (Nominal)(in)	Thickness Min. Dressed (Dry ≤19% MC)(in)	Thickness Min. Dressed (Green)(in)	Face Width (Nominal)(in)	Face Width Min. Dressed (Dry ≤19% MC)(in)	Face Width Min. Dressed (Green)(in)
Boards	3/8	5/16	11/32	2	1 1/2	1 9/16
	1/2	7/16	15/32	3	2 1/2	2 9/16
	5/8	9/16	19/32	4	3 1/2	3 9/16
	3/4	5/8	11/16	5	4 1/2	4 5/8
	1	3/4	25/32	6	5 1/2	5 5/8
	1 1/4	1	1 1/32	7	6 1/2	6 5/8
	1 1/2	1 1/4	1 9/32	8	7 1/4	7 1/2
				9	8 1/4	8 1/2
				10	9 1/4	9 1/2
				11	10 1/4	10 1/2
				12	11 1/4	11 1/2
				14	13 1/4	13 1/2
				16	15 1/4	15 1/2
Dimension Lumber	2	1 1/2	1 9/16	2	1 1/2	1 9/16
	2 1/2	2	2 1/16	2 1/2	2	2 1/16
	3	2 1/2	2 9/16	3	2 1/2	2 9/16
	3 1/2	3	3 1/16	3 1/2	3	3 1/16
	4	3 1/2	3 9/16	4	3 1/2	3 9/16
	4 1/2	4	4 1/16	4 1/2	4	4 1/16
	5	4 1/2	4 5/8	5	4 1/2	4 5/8
	6	5 1/2	5 5/8	6	5 1/2	5 5/8
	8	7 1/4	7 1/2	8	7 1/4	7 1/2
	10	9 1/4	9 1/2	10	9 1/4	9 1/2
	12	11 1/4	11 1/2	12	11 1/4	11 1/2
	14	13 1/4	13 1/2	14	13 1/4	13 1/2
	16	15 1/4	15 1/2	16	15 1/4	15 1/2
Timbers	5 & 6 thick	1/2 off nominal	1/2 off nominal	5 & 6 wide	1/2 off nominal	1/2 off nominal
	7 - 15 thick	3/4 off nominal	1/2 off nominal	7 - 15 wide	3/4 off nominal	1/2 off nominal
	≥ 16 thick	1 off nominal	1/2 off nominal	≥ 16 wide	1 off nominal	1/2 off nominal

Source: engineeringtoolbox.com

Note: All dimensions are in inches. Conversion: 1 inch = 25.4 mm.