Definition
The term Board Foot (BF) refers to a unit of measure used primarily in the lumber industry to quantify the volume of lumber. A board foot is defined as the volume of a piece of wood that is one foot long, one foot wide, and one inch thick, equivalent to 144 cubic inches. When discussing board feet, it is essential to distinguish between nominal (pre-milling) and actual dimensions, as lumber sizes reduce after drying and planing.
Examples
Example 1: Calculation of a Board Foot
- A plank of wood with dimensions of 1 × 6 inches (nominal size), and two feet in length.
To calculate the board footage:
- Width (in inches): 6
- Thickness (in inches): 1
- Length (in feet): 2
\[ \text{Board Foot} = \frac{\text{Width (in inches)} \times \text{Thickness (in inches)} \times \text{Length (in feet)}}{12} \]
\[ \text{Board Foot} = \frac{6 \times 1 \times 2}{12} = 1 \text{ BF} \]
Example 2: Multiple Dimensions
- Consider several pieces of lumber:
- Three pieces measuring 2"x4"x10’ (nominal size).
- Five pieces measuring 1"x6"x8’ (nominal size).
Calculate the board footage for each type of lumber:
- For the 2"x4"x10’ pieces:
\[ \text{Board Foot per piece} = \frac{2 \times 4 \times 10}{12} = 6.67 \text{ BF} \]
\[ \text{Total for three pieces} = 6.67 \times 3 = 20.01 \text{ BF} \]
- For the 1"x6"x8’ pieces:
\[ \text{Board Foot per piece} = \frac{1 \times 6 \times 8}{12} = 4 \text{ BF} \]
\[ \text{Total for five pieces} = 4 \times 5 = 20 \text{ BF} \]
Total Board Feet:
\[ 20.01 \text{ BF} + 20 \text{ BF} = 40.01 \text{ BF} \]
Frequently Asked Questions (FAQ)
What is meant by nominal dimensions in lumber?
Nominal dimensions refer to the original dimensions of lumber before it undergoes drying and milling. After these processes, the actual dimensions will be smaller than the nominal listed size.
How do you convert cubic feet to board feet?
To convert cubic feet to board feet, multiply the total cubic feet by 12 since there are 12 board feet in a cubic foot.
Why is it important to understand board feet in construction?
Understanding board feet is crucial for accurately estimating the amount of lumber needed for projects, determining costs, and coordinating supplies.
Can the board foot be applied to all types of lumber?
Yes, the board foot method can be used to measure all types of processed wood, although for irregular shapes or non-standard dimensions, conversions may be necessary.
Related Terms
- Nominal Size: The original dimension of lumber before drying and planing.
- Actual Size: The dimension of lumber after it has been dried and planed.
- Linear Foot: A measure of length used to denote how long a piece of lumber runs.
- Cubic Foot: A unit of volume representing a cube with edges one foot in length.
- Face Foot: Sometimes used in cabinet making, representing the lumber area with known thickness.
Online Resources
- The Wood Database
- Offers comprehensive data on different wood types.
- Calculator Soup - Board Feet Calculator
- An online tool to help compute board footage.
- Woodworking and Lumber Data from Fine Woodworking
- Guide and techniques related to measuring and using lumber.
Suggested Books for Further Study
- “Understanding Wood: A Craftman’s Guide to Wood Technology” by R. Bruce Hoadley
- “The Woodworker’s Bible: A Complete Guide to Woodworking” by Percy Blandford
- “Turning Wood with Richard Raffan” by Richard Raffan
- “Carpentry Complete: Expert Advice from Start to Finish” by Andy Engel
Real Estate Basics: Board Foot Fundamentals Quiz
