Northern Red Oak
Quercus rubra · hardwood · Eastern North America · moderate movement
- Janka hardness 1,290 lbfred oak ≈ 1,290 lbf
- Density ≈ 44 lb/ft³specific gravity 0.63 at 12% MC
- Shrinkage — tangential 8.6%flatsawn width, green → ovendry
- Shrinkage — radial 4%quartersawn width
- T/R ratio 2.1 : 1higher = more cupping in flatsawn stock
Shop notes The default American hardwood — open-grained, strong, honest to work. The 2:1 tangential-to-radial ratio is why flatsawn red oak panels cup; quartersawn stock is the cure.
Seasonal movement at a glance
Width change for northern red oak 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″ (0.111″) | 1/16″ (0.051″) |
| 12″ | 7/32″ (0.221″) | 3/32″ (0.103″) |
| 24″ | 7/16″ (0.442″) | 7/32″ (0.206″) |
| 36″ | 21/32″ (0.663″) | 5/16″ (0.309″) |
Run your own numbers
Different width, different climate swing — the calculator below is preset to northern red oak:
Typical swings:
Northern Red Oak questions
How much does northern red oak move with the seasons?
A 12″-wide flatsawn northern red oak board moves about 7/32″ across a typical indoor swing from 6% to 12% moisture content; quartersawn, about 3/32″. Its tangential shrinkage is 8.6% and radial 4% (green to ovendry) — a moderate-movement wood.
How hard is northern red oak?
Northern Red Oak rates about 1,290 lbf on the Janka scale — in red oak’s hardness neighborhood (red oak is roughly 1,290 lbf). Density runs about 44 lb/ft³ at indoor moisture levels.
Is northern red oak good for wide panels and tabletops?
Carefully. Its tangential-to-radial ratio of 2.1:1 makes flatsawn boards prone to cupping — choose quartersawn stock for wide glue-ups, alternate growth rings, and fasten tops so they can slide.
Similar species
American Beech · White Ash · Yellow Birch · Rock Elm · Iroko · White 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.