Board Foot (bd ft) – Definition, Symbol, Conversions, Uses and Applications

The board foot (bd ft) is a specialized unit of volume used in the lumber and woodworking industries to measure the amount of wood contained in a board or piece of timber. One board foot is equal to the volume of a board that is 1 foot long, 1 foot wide, and 1 inch thick. Although it is not part of the International System of Units (SI), the board foot remains one of the most widely used units for buying, selling, pricing, and estimating lumber in North America. Understanding the board foot is essential for carpenters, contractors, woodworkers, lumber suppliers, and anyone involved in construction or woodworking projects.

What Is a Board Foot?

A board foot is a unit of volume specifically designed for measuring lumber. It represents the volume of wood contained in a board measuring one foot in length, one foot in width, and one inch in thickness.

Mathematically, one board foot contains exactly 144 cubic inches of wood. The unit simplifies lumber calculations because boards come in many different sizes and dimensions. Instead of measuring cubic volume directly, lumber quantities are often expressed in board feet.

Board Foot Symbol

The standard symbol for the board foot is bd ft. It is also commonly abbreviated as BF or FBM (Foot, Board Measure) in the lumber industry.

Examples:

• 1 bd ft = 144 cubic inches
• 10 bd ft = 1,440 cubic inches
• 100 bd ft = 14,400 cubic inches

Board Foot to Other Units

The board foot can be converted into various volume units commonly used in construction and engineering.

• 1 Board Foot = 144 Cubic Inches
• 1 Board Foot = 0.083333 Cubic Feet
• 1 Board Foot = 0.00235974 Cubic Meters
• 1 Board Foot = 2.35974 Liters
• 1 Board Foot = 2,359.74 Milliliters
• 1 Board Foot = 0.083333 ft³
• 1 Board Foot = 1/12 Cubic Foot

History of the Board Foot

The board foot originated in the North American lumber industry as a practical method for measuring timber and sawn wood products. Since lumber is typically sold in boards of varying thicknesses, widths, and lengths, traditional cubic volume units were often inconvenient for commercial transactions.

The board foot became the standard unit for estimating lumber quantities, simplifying pricing, inventory management, and construction planning. Today, it remains widely used throughout the United States and Canada.

Common Uses of the Board Foot

The board foot is used primarily in industries that deal with wood products and timber.

Lumber Sales

Lumber yards and timber suppliers commonly sell wood based on board feet. Pricing is often expressed as a cost per board foot, making it easier to compare different wood species and dimensions.

Construction Projects

Contractors use board feet to estimate the amount of lumber required for framing, roofing, flooring, decking, and other structural components.

Woodworking

Furniture makers and woodworkers frequently calculate board feet when purchasing hardwoods for cabinets, tables, shelves, and custom projects.

Forestry Industry

Foresters and timber companies use board feet to estimate the value and yield of standing trees and harvested timber.

Project Cost Estimation

Architects, builders, and estimators often use board-foot calculations to determine material costs and project budgets.

How to Calculate Board Feet

The board foot can be calculated using the following formula:

Board Feet = (Thickness × Width × Length) ÷ 144

Where:

• Thickness is measured in inches.
• Width is measured in inches.
• Length is measured in inches.

Alternatively, when the board length is measured in feet:

Board Feet = (Thickness × Width × Length in Feet) ÷ 12

Example:

• Board size: 2 in × 8 in × 10 ft
• Board Feet = (2 × 8 × 10) ÷ 12
• Board Feet = 13.33 bd ft

Advantages of Using Board Feet

• Provides a standardized method for measuring lumber.
• Simplifies lumber pricing and purchasing.
• Widely recognized throughout the woodworking industry.
• Supports accurate project planning and material estimation.
• Works effectively for boards of different dimensions.

Board Foot vs Cubic Foot

Although both units measure volume, they serve different purposes.

• 1 Board Foot = 0.083333 Cubic Feet
• 1 Cubic Foot = 12 Board Feet

The cubic foot measures total volume regardless of shape, while the board foot is specifically designed for lumber measurement.

How to Convert Board Feet

Converting board feet to other volume units is straightforward.

• To convert board feet to cubic feet, divide by 12.
• To convert board feet to cubic meters, multiply by 0.00235974.
• To convert board feet to liters, multiply by 2.35974.
• To convert cubic feet to board feet, multiply by 12.

Examples:

• 25 bd ft = 2.0833 ft³
• 50 bd ft = 0.11799 m³
• 100 bd ft = 235.97 L
• 500 bd ft = 41.67 ft³

Interesting Facts About the Board Foot

• One board foot contains exactly 144 cubic inches.
• The unit was developed specifically for lumber measurement.
• Board-foot pricing is standard throughout much of North America.
• A cubic foot contains exactly 12 board feet.
• The unit is widely used in forestry, construction, and woodworking industries.

Conclusion

The board foot (bd ft) is a specialized volume unit used to measure lumber and timber products. Equal to the volume of a board measuring one foot by one foot by one inch, it provides a practical and standardized method for estimating wood quantities. From lumber yards and construction sites to woodworking shops and forestry operations, the board foot remains an essential measurement unit for professionals working with wood. Understanding board-foot calculations and conversions helps improve accuracy in material estimation, purchasing, and project planning.