Wood movement chart by species
How much a 12" board moves across the grain between a 30% winter and a 70% summer. Flatsawn moves roughly twice what quartersawn does, which is most of what this table is for.
| Species | Flatsawn, 12" board | Quartersawn, 12" board | As % of width |
|---|---|---|---|
| Walnut | 1/4" | 1/8" | 1.9% |
| White oak | 5/16" | 1/8" | 2.5% |
| Red oak | 5/16" | 1/8" | 2.5% |
| Hard maple | 5/16" | 1/8" | 2.4% |
| Soft maple | 1/4" | 1/8" | 2.0% |
| Cherry | 3/16" | 1/8" | 1.7% |
| Poplar | 1/4" | 1/8" | 2.0% |
| Ash | 1/4" | 1/8" | 1.9% |
| Hickory | 5/16" | 3/16" | 2.8% |
| Mahogany | 3/16" | 1/8" | 1.6% |
| Sapele | 1/4" | 1/8" | 1.9% |
| White pine | 3/16" | 1/16" | 1.4% |
| Douglas fir | 3/16" | 1/8" | 1.8% |
| Cedar | 3/16" | 1/16" | 1.6% |
Reading it
- Across the grain only. Movement along the grain is small enough to ignore in furniture.
- Half the figure is what a fastener has to allow in each direction from where you built it.
- Scale it: a 24" board moves twice this, a 6" board half.
- Coefficients are USDA Wood Handbook measured properties. The humidity range is the assumption worth changing for your own climate.
Sources: Wood Handbook: Wood as an Engineering Material (FPL-GTR-282, 2021), USDA Forest Service, Forest Products Laboratory.
For the case this table does not cover
- Wood movement
How far a panel expands and shrinks with the seasons, and what that means for the joint holding it.
- Board foot calculator
How much lumber to buy for a finished piece, what it will cost, and what to ask for at the yard.
The tool this table is for
- Jointer and planer
Milling rough stock flat and square, and how much of the board you pay for and then remove.