White Oak

Quercus alba · Hardwood · North America

Janka 1,360 lbf≈42 lb/ft³ dried (est.)Durable

Properties

Janka hardness	1,360 lbf (6,049 N)
Average dried weight (est.)	42 lb/ft³ (680 kg/m³)
Specific gravity	0.68
Modulus of rupture	15,200 psi (104.8 MPa)
Modulus of elasticity	1.78 million psi (12.27 GPa)
Crushing strength	7,440 psi (51.3 MPa)
Shrinkage — radial	5.6%
Shrinkage — tangential	10.5%
Shrinkage — volumetric	16.3%
Shrinkage T/R ratio	1.9

Values at 12% moisture content, clear-wood averages. Source: USDA Forest Products Laboratory, Wood Handbook FPL-GTR-282 (2021), Table 5–3b p. 5–11; shrinkage Table 4–3 p. 4–8.

White oak is the tight-cooperage oak: its heartwood pores are plugged with tyloses, making the wood nearly impenetrable to liquids. High-quality white oak is especially sought for tight cooperage, ship and boat planking, furniture, flooring, and millwork.

Appearance & grain

The sapwood is nearly white and roughly 2 to 5 cm wide, and the heartwood is generally grayish brown. The heartwood pores are usually plugged with tyloses, which tends to make the wood impenetrable to liquids.

Durability

Rated as having good decay resistance in the heartwood — a reason heartwood is often specified for the planking and bent parts of ships and boats.

Workability

White oak is somewhat heavier than red oak, and its shrinkage and strength sit at the top of the oak groups in the Handbook's tables. The tyloses sealing its heartwood pores are what make most white oaks suitable for tight cooperage without linings.