Privacy Fence Calculator
Estimate how many boards, posts, rails, and concrete bags you need for a board-on-board privacy fence. Enter your fence length and spacing below — results update instantly.
Privacy Fence Calculator
Board count includes 10% waste. Results are estimates — buy extra for cuts and defects. Need a full multi-segment calculator? →
About Privacy Board-on-Board Fences
A board-on-board privacy fence is the most popular style of wood privacy fence in the United States. Vertical boards are nailed to horizontal rails, with each board overlapping the previous one by 1 to 1.5 inches. The overlapping pattern means there are no gaps even if boards warp or shrink seasonally — and the fence looks identical from both sides, making it a good neighbor option.
Boards are typically cedar (naturally rot-resistant) or pressure-treated pine. Cedar costs more but holds stain better and resists insects. Pressure-treated pine is more affordable and extremely durable, though it must be allowed to dry before painting or staining. Both are widely available at Home Depot, Lowe's, and local lumber yards.
Privacy Fence Material Breakdown
| Material | Typical Size | Notes |
|---|---|---|
| Fence Posts | 4×4 or 6×6, 8–10 ft long | Set 2 ft in ground for a 6 ft fence; 2.5 ft for an 8 ft fence |
| Horizontal Rails | 2×4, 8 ft long | 3 rails per bay for 6 ft fence; 4 rails for 8 ft fence |
| Fence Boards | 1×6 (5.5" face), fence length | Overlap 1.5" per board; cedar or pressure-treated |
| Concrete | 80 lb bags (fast-setting) | 2 bags per post for standard 8 ft spacing |
| Post Caps | 4×4 or 6×6 cap | Optional but protects post tops from rot |
Privacy Fence vs Solid Board Fence
Board-on-board and solid board privacy fences look similar at a glance but differ in a key way: a solid board fence nails boards edge-to-edge on one side of the rail with no overlap. This uses fewer boards, but gaps appear as boards dry and shrink. A board-on-board fence overlaps boards, so it uses slightly more material but stays gap-free even as wood moves.
| Board-on-Board | Solid Board | |
|---|---|---|
| Gaps over time | None (overlap compensates) | Yes (boards shrink) |
| Two-sided look | Yes | No (one finished side) |
| Board count | ~30% more boards | Fewer boards |
| Privacy | Complete | Complete when new; gaps later |
Frequently Asked Questions
How many boards do I need for a 100-foot privacy fence?
A 100-foot board-on-board privacy fence using 5.5-inch wide boards (1×6 nominal) with 1.5-inch overlap needs approximately 384 boards including 10% waste.
How many posts for a privacy fence?
A 100-foot privacy fence with 8-foot post spacing needs 14 posts. For taller 8-foot privacy fences, reduce post spacing to 6 feet, which requires 18 posts per 100 feet.
How many rails does a privacy fence need?
A standard 6-foot privacy fence uses 3 rails (top, middle, bottom) per bay. An 8-foot fence may use 4 rails for added strength. Rails are typically 2×4 lumber cut to fit between posts.
What is board-on-board fencing?
Board-on-board fencing alternates vertical boards on each side of the horizontal rail, with each board overlapping the next by 1–2 inches. This creates a fence that looks good from both sides and has no gaps, even as boards shrink over time.
How deep should privacy fence posts be set?
The general rule is to bury one-third of the post length. For a 6-foot above-ground fence, use a 9-foot post and bury 3 feet. For an 8-foot above-ground fence, use an 11-foot post and bury about 3.5 feet. Always check local frost depth requirements — in cold climates, posts must go below the frost line.