Calculate board feet and cost for lumber orders
A board foot is a unit of volume equal to a board 12 inches wide, 12 inches long, and 1 inch thick. Formula: (T" × W" × L') / 12.
Lumber is often sold by nominal dimensions (e.g., 2x4), but actual dimensions are smaller (1.5x3.5). Board foot calculations usually use nominal dimensions.
Hardwoods are often sold by the board foot, while softwoods (like construction lumber) are often sold by the linear foot or per piece.
Board feet (BF) is the standard unit for measuring lumber. One board foot = 1 foot long × 1 foot wide × 1 inch thick. Lumber is priced per board foot.
Calculating board feet helps you estimate material quantity and cost for construction projects. This measurement accounts for length, width, and thickness of lumber pieces.
Piece: 2×4×10 feet
Calculation: (2 × 4 × 10) ÷ 12 = 80 ÷ 12 = 6.67 board feet
10 pieces: 6.67 × 10 = 66.7 board feet
Cost at $0.75/BF: 66.7 × $0.75 = $50.03
Board feet accounts for thickness and width, not just length. A 2×4 is different from a 1×4 at same length.
Nominal: 2×4. Actual: 1.5×3.5 inches (after milling). Use actual dimensions for board feet calculation.
Common (utility), #2, #1, premium/select. Higher grades cost more but have fewer defects.
Keep horizontal with spacers between layers. Cover top to prevent weather damage. Allow air circulation.
Softwood (pine, fir): cheaper, lighter, easier to work. Hardwood (oak, maple): harder, more durable, more expensive.
Usually within 30 days with receipt. Check store policy. Return must be in sellable condition.
Add 10-15% to account for waste, defects, and mistakes. Better to have extra than run short.
Wood treated with preservatives to resist rot and insects. Required for ground contact/outdoor use. Avoid eating from treated wood.
Disclaimer: Lumber board feet calculations are based on nominal dimensions. Actual finished dimensions are smaller due to milling. Prices vary by wood type, grade, location, and market conditions. Always verify actual dimensions and prices with your supplier before ordering. Add 10-15% waste factor for your project. This calculator is for planning purposes only. Actual material needs may vary based on project specifics.
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