Field data
  • Janka hardness 1,400 lbfred oak ≈ 1,290 lbf
  • Density ≈ 47 lb/ft³specific gravity 0.67 at 12% MC
  • Shrinkage — tangential 10.8%flatsawn width, green → ovendry
  • Shrinkage — radial 4.4%quartersawn width
  • T/R ratio 2.5 : 1higher = more cupping in flatsawn stock

Shop notes Dense red-oak-group timber with a big flatsawn movement number; behaves in the shop like heavy red oak.

Seasonal movement at a glance

Width change for scarlet oak across a typical indoor year — 6% moisture content in the heated winter to 12% in a humid summer:

Board widthFlatsawnQuartersawn
6″ 1/8″ (0.139″) 1/16″ (0.057″)
12″ 9/32″ (0.278″) 1/8″ (0.113″)
24″ 9/16″ (0.555″) 7/32″ (0.226″)
36″ 27/32″ (0.833″) 11/32″ (0.339″)

Run your own numbers

Different width, different climate swing — the calculator below is preset to scarlet oak:

Board & conditions
Grain
Conditions given as

Typical swings:

Scarlet Oak questions

How much does scarlet oak move with the seasons?

A 12″-wide flatsawn scarlet oak board moves about 9/32″ across a typical indoor swing from 6% to 12% moisture content; quartersawn, about 1/8″. Its tangential shrinkage is 10.8% and radial 4.4% (green to ovendry) — a high-movement wood.

How hard is scarlet oak?

Scarlet Oak rates about 1,400 lbf on the Janka scale — in red oak’s hardness neighborhood (red oak is roughly 1,290 lbf). Density runs about 47 lb/ft³ at indoor moisture levels.

Is scarlet oak good for wide panels and tabletops?

Carefully. Its tangential-to-radial ratio of 2.5:1 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

Sapele · Bur Oak · White Oak · Post Oak · Sugar Maple (Hard Maple) · Sweet Birch

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.