Understanding Board Feet
A board foot is the standard unit for measuring lumber volume. One board foot equals a piece of wood 12 inches long, 12 inches wide, and 1 inch thick (144 cubic inches). This measurement helps standardize pricing across different lumber dimensions.
Board Foot Formula
Board Feet = (Thickness x Width x Length) / 144
Where thickness and width are in inches, and length is in inches (or divide by 12 if length is in feet).
Common Lumber Sizes
| Nominal Size | Actual Size | Common Use |
|---|---|---|
| 2x4 | 1.5" x 3.5" | Wall studs, framing |
| 2x6 | 1.5" x 5.5" | Floor joists, exterior walls |
| 2x8 | 1.5" x 7.25" | Floor joists, headers |
| 2x10 | 1.5" x 9.25" | Floor joists, beams |
| 2x12 | 1.5" x 11.25" | Floor joists, stair stringers |
| 4x4 | 3.5" x 3.5" | Posts, columns |
Lumber Grades
| Grade | Quality | Best For |
|---|---|---|
| Select/Clear | Highest | Furniture, trim, visible areas |
| #1 Common | High | Cabinets, shelving |
| #2 Common | Standard | General construction |
| Construction Grade | Economy | Framing, non-visible |
Wood Species Recommendations
- Douglas Fir: Strong, ideal for framing and structural applications
- Southern Pine: Accepts treatment well, great for outdoor use
- Cedar: Naturally rot-resistant, perfect for decks and fencing
- Redwood: Beautiful grain, excellent for outdoor furniture
- Oak: Hardwood, best for furniture and flooring
- Pine: Economical, good for interior projects
Lumber Buying Tips
- Always buy 10-15% extra for waste and mistakes
- Inspect each board for warping, twisting, and knots
- Check moisture content - under 19% for construction lumber
- Store lumber flat and off the ground to prevent warping
- Acclimate lumber to job site conditions before use
- Use pressure-treated lumber for ground contact applications