1. Wood Products Lumber Measurements Calculations
Industrial Skills
Wood Products
Lumber Measurements
Calculations

2. Wood Products Two Broad Groups Hardwoods – Broad-leaved trees.
White Oak
Mahogany
Teak
Softwoods – Coniferous trees
White Cedar (Juniper)
Cypress
Pines

3. Softwood Lumber Use Classifications
Yard Lumber – Less than 5” in thickness, intended for ordinary construction and general building purposes.
Select – good appearance and finishing qualities.
Grades A-D (see handout)
Common – general construction and utility.
Numbers 1-5 (see handout)
Structural Lumber – 2” or more in both thickness and width, used where working stresses are required.

4. Softwood Lumber Manufacturing Classifications Rough Lumber-
Lumber that has not been dressed (surfaced).
Dressed/Surfaced Lumber-
Lumber that has been dressed by a planing machine for a smooth surface and uniformity of size. Most commonly on all sides and edges.
Worked Lumber-
Dressed lumber that has been matched, shiplapped, or patterned.
*Note table of standard sizes of lumber in your handout
“Materials & Industrial Standards”.

5. Softwood Lumber Size Classifications Nominal/Rough – Actual/Dressed –
Refers to the “nominal” size (in inches) of the board before it is dressed and dried
A 1 x 4 or a 2 x 4
Actual/Dressed –
Refers to the finished (dressed and dried) “actual” size of the lumber
A 1 x 4 is actually ¾” x 3 ½”
A 2 x 4 is actually 1 ½” x 3 ½”
*Note table of standard sizes of lumber in your handout
“Materials & Industrial Standards”.

6. Softwood Lumber Boards – Dimension Lumber –
less than 2 inches thick and at least 2 inches wide in nominal dimensions
Ex) 1 x 4 or a 1 x 6
Dimension Lumber –
2 to 5 inches thick and at least 2 inches wide in nominal dimensions
Ex) 2 x 4 or a 4 x 4
Standard lengths of lumber are generally 6 feet and longer in multiples of 2 feet.
Ex) 1 x 4 x 6 (1” x 4” x 6’) or 2 x 6 x 10 (2” x 6” x 10’)
*Note table of standard sizes of lumber in your handout
“Materials & Industrial Standards”.

7. Grading Standards Softwood Hardwood
graded by the best side of the board.
Hardwood
graded by the worst side of the board

8. Hardwood Lumber
Factory lumber – grades reflect the proportion of a piece that can be cut into useful smaller pieces.
Dimension lumber – grades are based on the entire piece.
Finished Market Products – graded for their end use with little or no remanufacture. (molding, flooring, etc.)
Hardwood Lumber is sold by random widths and lengths.

9. Measurements and Pricing
Lumber may be priced and sold:
By the piece.
By the lineal foot.
By the square foot (composites and plywood).
By the board foot.
Generally, when ordering large quantities of softwoods or any marine grade hardwood, you will receive a price per board foot.
When calculating board feet always use the nominal size or in the case of hardwoods, the actual rough size.

10. Measurements and Pricing:
Board foot = 144 cubic inches
Board Feet can be calculated in several ways.
# of pieces x Thickness (in.) x Width (in.) x Length (in.)
# of pieces x Thickness (in.) x Width (in.) x Length (ft.)*
Divided by 144
Divided by 12
*This particular formula represents one of the few exceptions to the rule of always using like units when performing calculations.

11. Measurements and Pricing: Board Foot Examples
144 cu. Inches =1 Board Foot
1 x 6 x 2
1 x 12 x 12
144 cu. Inches
1 Board Foot 1”
24” 1”
12”
12” 6”
12”
2 x 6 x 1
144 cu.in.
1 board foot
1 x 4 x 3
144 cu. Inches =1 Board Foot 1” 2” 4”
36” 6”

12. Measurements and Pricing: Board Foot Calculations
A “piece” of mahogany measuring 1 inch thick, 9½ inches wide, and 36 inches long would contain how many board feet?
# of pieces x T” x W” x L” = 1 x 1” x 9½” x 36”
= 342” = Board Feet
OR, because 36” = 3’
# of pieces x T” x W” x L’ = 1 x 1” x 9½” x 3’
= = Board Feet
144
144
144 12 12 12

13. Measurements and Pricing: Board Foot Calculations
A “piece” of dressed yellow pine measuring ¾ inch thick, 5½ inches wide and 12 feet long would contain how many board feet.
# of pieces x T” x W” x L” = 1 x 1” x 6” x 144”
= 864” = 6 Board Feet
Or # of pieces x T” x W” x L’ = 1 x 1” x 6” x 12’
= 72 = 6 Board Feet
144
144
144 12 12 12

14. Industrial Applications: Lumber Quantity Question – Dock
A boat dock your agency uses is in need of repair. The pilings, cross-members, and stringers are all in good shape. You are asked to calculate the amount of lumber needed to replace all the existing deck boards with new treated 2 x 4. A ½” gap should be left between each deck board to allow water to adequately drain. The dock is 12 foot wide and 80 feet long.
What is the total lineal feet needed?
Lineal feet = total length of material needed
What is the total board footage needed?

15. Industrial Applications: Lumber Quantity Question – Dock
12’
80’
Understanding the standard sizes of lumber will make your calculations much easier.
A treated 2 x 4 measures 1½” x 3½” .
So, the ½ inch gap is included in the 4” nominal width.
You would want to order 12’ long boards.
80 feet = 960 inches ” divided by 4” = 240 boards
Therefore you could order 240, 2 x 4 boards that are 12’ long
The lineal feet would equal, 240 bds. X 12’ = 2880 Lineal feet

16. Industrial Applications: Lumber Quantity Question – Dock
12’
80’
So, we have 240 boards that are 2” by 4” (remember to use nominal dimensions) and are each 12 feet long (144 inches)
To find board feet:
# of pieces x T” x W” x L’ = 240 x 2” x 4” x 12’ = = bd.ft.

17. Industrial Applications: Lumber Quantity Question – Dock
12’
80’
If you ever need to convert board feet to lineal feet, simply reverse the multiple used to bring lineal feet to board feet. In other words:
Board Feet x 12” x 12” = = 2880 Lineal feet
Thickness (in) x Width (in) ” x 4”

18. Plywood A panel with layers, or plies, of wood veneer
Very strong - equally strong with and across the grain
odd number of layers glued together with the grains of each layer at right angles to each other
Face and Back
Face: “top” layer, typically higher quality of wood
Back: “bottom” layer

19. Plywood Softwood: Hardwood:
Most common and used in building construction
Hardwood:
Finer Face, used in furniture and boat interiors

20. Softwood Plywood Grading
Located on the edge or back is a “grade stamp” N, A, B, C, C plugged, or D
See “Standard Veneer Grades” table in handout
The Face and Back can have separate grades

21. Softwood Plywood Interior Exterior Marine
Core contains veneers of D grade or better
Bonded with moisture resistant glue
Exterior
Core contains veneers of C grade or better
Bonded with waterproof glue
Marine
No voids in its core
Made to withstand continuous exposure to water

22. Hardwood Plywood Only concerned with Face and Back, not core Grades:
Premium
Good
Sound
Utility
Backing
Grades are usually abbreviated. If only one, it refers to the face

23. Hardwood Plywood Type I Type II
Has exterior glue and is waterproof
Type II
Has interior glue and accounts for 95% of all domestic hardwood plywood
Solid Core is also available (no voids or holes)

24. Plywood Sizes Common thicknesses Common width and length
4’ x 8’
2’ x 4’ is available and special order lengths of 10’, 12’, and 16’

25. Plywood Pricing You can be quoted by “per sheet”
Ex) one 4’x8’ sheet of ½” A/C exterior grade plywood = X $
You can be quoted by square foot
A piece of ½” x 4’ x 8’ plywood has 32sqft
L” x W” or L’ x W’
144