Reviewed and updated: September 23, 2026.
A board sold as 1×6 may not measure one inch by six inches. Nominal lumber sizes are product names; actual dimensions describe the piece you receive. For a fence, that difference affects the appearance, quantity of boards, and fit at gates and corners.
Start with the supplier’s stated dimensions and a sample. Fence pickets can be rough-sawn, surfaced, or manufactured to specialty sizes, so a general lumber chart is not a substitute for measuring the specified product.
Common examples of nominal and actual sizes
The American Softwood Lumber Standard distinguishes nominal sizes from dressed dimensions. Common dry, surfaced lumber examples include a nominal 1×6 measuring ¾ inch by 5½ inches and a nominal 2×4 measuring 1½ inches by 3½ inches. These examples do not mean every fence picket sold under a similar label has those dimensions.
- Thickness: Measure the narrow edge of the board.
- Width: Measure across its face.
- Length: Confirm the usable length after decorative cuts or trimming.
- Surface: Confirm whether the quoted material is rough or surfaced.
Write the actual size beside the product name when comparing estimates. “Cedar privacy boards” leaves far more open to interpretation than a description naming species, grade, dimensions, and finish.
Calculate coverage using the intended layout
For a simple side-by-side layout, board width plus the planned gap determines the repeating coverage. For example, a 5½-inch board with a ½-inch gap gives six inches per repeat. A 120-inch straight run would have 20 repeats before adjusting the end layout. This is an illustration, not a recommended privacy-fence gap.
Board-on-board designs need a different calculation because the second layer overlaps the first. Gates, corner details, decorative cuts, and unusable boards also change the order quantity. Have the installer explain the layout instead of buying only from total linear fence length.
Thickness is one part of the assembly
A thicker board changes the material in the fence, but thickness alone does not establish wind resistance or a permitted fence height. Post size, spacing, footings, rail spans, connections, and the amount of open area work together.
Horizontal boards especially deserve a discussion about unsupported span and intermediate support. Ask for the detail that keeps the proposed boards aligned. A drawing or sample panel is more useful than a promise that any particular thickness will never sag or warp.
Specify species, grade, and treatment
Species names are not grades. Ask how knots, surface appearance, and defects will be handled, and which side will face the primary viewing area. Compare the visible boards separately from posts and rails; they may use different materials.
For pressure-treated wood, use the treatment label and intended exposure. AWPA identifies use categories for the service conditions. A single preservative retention number cannot be applied to every treatment chemistry. Color alone does not prove that a piece is correctly treated.
Ask how cut ends will be handled under the product guidance and which hardware is compatible with the treated material. Keep a label or invoice showing the actual specification.
Allow for wood movement
Wood responds to moisture. The initial condition of the boards and the intended layout affect spacing decisions. Have the installer explain how the design balances privacy with the material’s expected movement.
Do not specify one moisture percentage or gap for every wood species and fence style. A solid privacy layout, shadowbox fence, and horizontal slat fence have different appearance goals. Review the expected result from the street and from inside the yard.
A useful estimate comparison checklist
- Exact board species, actual size, and grade.
- Post and rail specification, including treatment where applicable.
- Board orientation, spacing, overlap, and finished height.
- Hardware and gate details.
- Staining or finishing scope and responsibility.
- Removal, access, cleanup, and written warranty terms.
Use our wood fence gallery and options to identify the look you want. Then use dimensions and a written specification to make sure each estimate describes that same fence.
A worked example: why coverage and board count differ
Imagine a straight 10-foot opening to be covered with side-by-side boards measuring 5½ inches wide, with no planned gaps. The opening is 120 inches. Dividing 120 by 5½ gives about 21.8, so 22 boards would provide enough nominal coverage before cutting and laying out the ends. Twenty boards would cover only 110 inches.
That arithmetic is useful, but it is not a complete order list. It assumes the measured width is consistent and the intended design permits that layout. A gate, trim, a change in height, or board-on-board overlap changes the calculation. Have the final count based on a measured layout.
What a thicker board changes at the connection
Changing board thickness can affect more than the visible edge. The fastener must still have the required engagement in the rail without creating an exposed point. Trim, brackets, gate clearances, and the overall weight may also need review.
When a quote offers an upgrade, ask whether the support and hardware specifications change with it. A thicker board fitted to an unchanged or unsuitable supporting system is not automatically a stronger complete fence. A heavier gate, in particular, needs its frame and post checked together.
Matching a replacement board to an older fence
Measure a sound piece rather than a split or badly cupped board. Record its thickness, width, length, top profile, and surface texture. Photograph the overall pattern and its connection to the rails. If possible, identify the species and finish from the original invoice.
A replacement can be dimensionally correct but still differ in color from weathered wood. Decide whether to accept that contrast, finish the repair area, or refinish a larger section according to the coating instructions. Do not assume a newly purchased board will immediately match an older run.
Before you accept a delivery
Check the delivered product against the written specification while labels are available. Measure a sample of pieces, confirm the grade and treatment identification, and set aside visibly damaged material for discussion with the supplier.
Agree on storage and protection until installation. Keep the supplier’s handling instructions with the material, and resolve a substitution before it is installed. That is easier than discovering afterward that two estimates used the same nominal label for different actual boards.
Plan your fence with Precision Fenceworks
Bring your photos, rough measurements, and the questions you still need answered. Request a free estimate or call (770) 725-0777 to discuss your property in Atlanta, Athens, Lawrenceville, or a nearby community.
Sources and product guidance
Sources checked for this update. Use the instructions and warranty for the exact product in your estimate.
