Sweet Birch
Betula lenta · hardwood · Eastern North America · moderate movement
- Janka hardness 1,470 lbfred oak ≈ 1,290 lbf
- Density ≈ 45 lb/ft³specific gravity 0.65 at 12% MC
- Shrinkage — tangential 9%flatsawn width, green → ovendry
- Shrinkage — radial 6.5%quartersawn width
- T/R ratio 1.4 : 1higher = more cupping in flatsawn stock
Shop notes The hardest of the birches, historically stained to imitate mahogany and cherry. Expect real seasonal movement in wide panels.
Seasonal movement at a glance
Width change for sweet birch across a typical indoor year — 6% moisture content in the heated winter to 12% in a humid summer:
| Board width | Flatsawn | Quartersawn |
|---|---|---|
| 6″ | 1/8″ (0.116″) | 3/32″ (0.084″) |
| 12″ | 7/32″ (0.231″) | 5/32″ (0.167″) |
| 24″ | 15/32″ (0.463″) | 11/32″ (0.334″) |
| 36″ | 11/16″ (0.694″) | 1/2″ (0.501″) |
Run your own numbers
Different width, different climate swing — the calculator below is preset to sweet birch:
Typical swings:
Sweet Birch questions
How much does sweet birch move with the seasons?
A 12″-wide flatsawn sweet birch board moves about 7/32″ across a typical indoor swing from 6% to 12% moisture content; quartersawn, about 5/32″. Its tangential shrinkage is 9% and radial 6.5% (green to ovendry) — a moderate-movement wood.
How hard is sweet birch?
Sweet Birch rates about 1,470 lbf on the Janka scale — in red oak’s hardness neighborhood (red oak is roughly 1,290 lbf). Density runs about 45 lb/ft³ at indoor moisture levels.
Is sweet birch good for wide panels and tabletops?
Yes, with normal precautions: its 1.4:1 tangential-to-radial ratio is unusually balanced, so panels stay flatter than most. Still fasten solid tops so they can move across their width.
Similar species
Sugar Maple (Hard Maple) · Pin Oak · Sapele · Scarlet Oak · Afrormosia · Bur Oak
Shrinkage, specific gravity, and hardness from the Wood Handbook, FPL-GTR-282 (2021 edition), USDA Forest Products Laboratory (public domain). Values are species averages — individual boards vary with growth conditions and how they were dried.