How Many Fence Pickets or Boards Do I Need?
Pickets and boards are bought by the piece, so a small error in the gap multiplies into a big error in the count. Here is how to work out exactly how many you need, with the right wastage built in.
By the Calculate My Reno Team / Published
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Open the Fence Calculator
Once the posts and rails are up, the pickets or boards are what you see - and what you buy by the hundred. A clear formula and an honest wastage allowance keep you from a second order.
The formula
Each picket takes up its own width plus the gap to the next one, so the count is the run length divided by that pitch:
pitch = picket width + gap
pickets = ceil(run length ÷ pitch × wastage)
The fence calculator runs this for every run and adds your chosen wastage, but you can do it by hand with those three numbers: run length, board width and gap.
The gap sets the style
The gap between boards is the single biggest choice, and it changes both the look and the count:
| Fence style | Gap | Look |
|---|---|---|
| Privacy / close-board | 0 | Solid, no see-through |
| Board-on-board | Negative (overlap) | Solid, more boards |
| Classic picket | Equal to picket width | Even spaced gaps |
| Spaced / ranch | Wider than picket | Open, fewest boards |
For privacy, set the gap to zero so boards butt together. For a picket fence, a gap equal to the picket width gives the traditional even rhythm.
Worked example
A 20 m run, 90 mm pickets, 10 mm gap, 10% wastage:
- Pitch: 90 + 10 = 100 mm (0.1 m).
- Bare count: 20 ÷ 0.1 = 200 pickets.
- With wastage: 200 × 1.10 = 220 pickets.
Building a spaced picket fence instead? With a 90 mm gap the pitch becomes 180 mm, so 20 ÷ 0.18 = 112 pickets before wastage - roughly half the boards of the close-board version.
A few tips
- Decide the gap before you order; a 5 mm change across a long run moves the count by several boards.
- Board-on-board and overlap (feather-edge) styles need extra boards for the overlap - allow for it in the gap or add to the count.
- Buy a few spare boards beyond the wastage to replace any that split when nailing.
- Counting the posts too? See how many fence posts do I need, then plan the finish with how much stain or paint for a fence.
Frequently asked questions
How do I calculate how many fence pickets I need?
Divide the run length by the picket width plus the gap, then add a wastage allowance. A 60 ft run with 3.5 in pickets and a 0.5 in gap is 60 ÷ (4 in) = 180 pickets, and 180 × 1.10 for 10% wastage is 198. The fence calculator does this per run and totals it for you.
What gap should I leave between fence pickets?
For a privacy or close-board fence, set the gap to zero so the boards butt or overlap with no see-through. For a classic spaced picket fence, a gap equal to the picket width gives an even look; smaller gaps look more solid. The gap has a big effect on the count, so set it before you order.
How much wastage should I add for fence boards?
Add about 10% on top of the bare count for cuts and the odd split or culled board, going to 15% for rough-sawn timber with more cutting. Machined, consistent boards can run closer to 5%. Pickets are where most fence waste happens, so this allowance matters more than on the posts or rails.
How many boards for a 6 ft privacy fence?
For privacy fencing the gap is zero, so the board count is the run length divided by the board width, plus wastage. A 20 m run with 90 mm boards is 20 ÷ 0.09 = 223 boards, and 223 × 1.10 is about 245 with 10% wastage. Overlapping or board-on-board styles need more boards for the same run, so allow for the overlap.