Softwood Lumber - Dimensions
Dimensional lumber is a term used for lumber that is finished - planed and cut - to a standardized width and depth specified in inches.
Commercial lumber dimensions - American Softwood Lumber Standards - nominal and actual sizes are indicated in the table below.
General rule converting nominal to actual softwood dimensions
- subtract 1/4 inch for dimensions under 2 inches (51 mm)
- subtract 1/2 inch for dimensions under 8 inches (200 mm)
- subtract 3/4 inch for larger dimensions
| Nominal Size (in x in) | Actual Size | ||
|---|---|---|---|
| (in x in) | (mm x mm) | Weight (lb/ft) | |
| 1 x 1 | 3/4 x 3/4 | 19 x 19 | 0.14 |
| 1 x 2 | 3/4 x 1 1/2 | 19 x 38 | 0.27 |
| 1 x 3 | 3/4 x 2 1/2 | 19 x 64 | 0.47 |
| 1 x 4 | 3/4 x 3 1/2 | 19 x 89 | 0.64 |
| 1 x 6 | 3/4 x 5 1/2 | 19 x 140 | 1.00 |
| 1 x 8 | 3/4 x 7 1/4 | 19 x 184 | 1.32 |
| 1 x 10 | 3/4 x 9 1/4 | 19 x 235 | 1.69 |
| 1 x 12 | 3/4 x 11 1/4 | 19 x 286 | 2.05 |
| 2 x 2 | 1 1/2 x 1 1/2 | 38 x 38 | 0.55 |
| 2 x 3 | 1 1/2 x 2 1/2 | 38 x 64 | 0.94 |
| 2 x 4 | 1 1/2 x 3 1/2 | 38 x 89 | 1.28 |
| 2 x 6 | 1 1/2 x 5 1/2 | 38 x 140 | 2.00 |
| 2 x 8 | 1 1/2 x 7 1/4 | 38 x 184 | 2.64 |
| 2 x 10 | 1 1/2 x 9 1/4 | 38 x 235 | 3.37 |
| 2 x 12 | 1 1/2 x 11 1/4 | 38 x 286 | 4.10 |
| 2 x 14 | 1 1/2 x 13 1/4 | 38 x 337 | 4.83 |
| 3 x 3 | 2 1/2 x 2 1/2 | 64 x 64 | 1.52 |
| 3 x 4 | 2 1/2 x 3 1/2 | 64 x 89 | 2.13 |
| 3 x 6 | 2 1/2 x 5 1/2 | 64 x 140 | 3.34 |
| 3 x 8 | 2 1/2 x 7 1/4 | 64 x 184 | 4.41 |
| 3 x 10 | 2 1/2 x 9 1/4 | 64 x 235 | 5.62 |
| 3 x 12 | 2 1/2 x 11 1/4 | 64 x 286 | 6.84 |
| 3 x 14 | 2 1/2 x 13 1/4 | 64 x 337 | 8.05 |
| 3 x 16 | 2 1/2 x 15 1/4 | 64 x 387 | 9.27 |
| 4 x 4 | 3 1/2 x 3 1/2 | 89 x 89 | 2.98 |
| 4 x 6 | 3 1/2 x 5 1/2 | 89 x 140 | 4.68 |
| 4 x 8 | 3 1/2 x 7 1/4 | 89 x 184 | 6.17 |
| 4 x 10 | 3 1/2 x 9 1/4 | 89 x 235 | 7.78 |
| 4 x 12 | 3 1/2 x 11 1/4 | 89 x 286 | 9.57 |
| 4 x 14 | 3 1/2 x 13 1/4 | 89 x 337 | 11.28 |
| 4 x 16 | 3 1/2 x 15 1/4 | 89 x 387 | 12.98 |
- 1 lb/ft = 1.48 kg/m
- 1 in (inch) = 25.4 mm
- Weight vs mass - the difference
Weight is based on dry wood with 35 lb/ft3 (560 kg/m3) actual volume.
- Rough Lumber - sawn, trimmed and edged - faces are rough with saw marks
- Surfaced Lumber (dressed) - Rough lumber that has been smoothed on one or more sides and edges by a surfacing machine.
- Worked Lumber - Surfaced lumber that has been matched and patterned
Dry lumber is defined as lumber with less than 19% moisture. Unseasoned or green lumber is lumber with more than 19% moisture.
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