White Oak, scientifically known as Quercus alba, is a deciduous hardwood tree distributed throughout the eastern United States. It has earned a reputation as a classic, high-performance wood, valued for its distinctive grain pattern and durability. This wood has been the material of choice for applications ranging from fine furniture and interior millwork to whiskey barrels and boatbuilding. Understanding its weight is fundamental because wood density directly correlates to its performance, strength, and suitability for various projects.
The Specific Weight of White Oak
The weight of wood is measured using two metrics: Specific Gravity (SG) and Weight per Cubic Foot (PCF). Specific Gravity is a ratio comparing the density of wood to the density of water, providing a standardized, unitless measure. White Oak possesses an average Specific Gravity of approximately 0.68 at the industry-standard 12% moisture content (MC), which is a high figure for a domestic hardwood.
This density translates to an average dried weight of about 47 pounds per cubic foot (PCF) for kiln-dried White Oak lumber. The industry also uses the weight per board foot (PBF) metric. One board foot of White Oak weighs approximately 3.9 pounds, making it a substantial material to handle in large quantities.
How Moisture Content Influences Weight
The most significant variable affecting wood weight is its moisture content (MC), which is the water contained within its cellular structure. Freshly felled White Oak, known as “green” lumber, holds substantial water, causing its weight to increase significantly. Green White Oak can weigh around 62 pounds per cubic foot or higher, representing an increase of over 30% compared to its dried state.
Kiln-drying reduces moisture to a stable level, typically 6% to 12% MC, which is the standard for interior use. This process stabilizes the wood and ensures a manageable weight for construction. Dried lumber will still fluctuate slightly in weight as it seeks equilibrium moisture content (EMC) with the surrounding air, absorbing or releasing humidity based on the local environment.
Weight Comparison to Common Hardwoods
White Oak’s density places it among the heavier domestic hardwoods. Compared to its closest relative, Red Oak (45 pounds per cubic foot at 12% MC), White Oak is slightly denser and heavier. This difference is attributed to the presence of tyloses, bubble-like structures that plug the wood’s vessels.
The weight difference is more pronounced when comparing White Oak to other popular woods. Hard Maple is comparable at around 43 pounds per cubic foot, while Black Walnut is lighter, averaging approximately 38 pounds per cubic foot. Comparing White Oak to common softwoods like Douglas Fir (32 pounds per cubic foot) or Southern Yellow Pine (38 pounds per cubic foot) shows a significant difference, highlighting the density gap between hardwoods and softwoods.
Practical Implications of White Oak’s Density
The high density of White Oak is responsible for its desirable performance characteristics. This structural compactness provides exceptional hardness, scoring approximately 1,360 pounds-force on the Janka scale. This hardness makes it highly resistant to dents, scratches, and wear, making it a preferred material for high-traffic flooring.
The dense cellular structure, combined with the pore-blocking tyloses, contributes to White Oak’s resistance to water absorption and decay. This natural barrier makes the heartwood durable in outdoor applications, leading to its historical use for decking, boat ribs, and liquid-tight cooperage. However, the high weight increases transportation costs and requires more effort during installation or construction.