How Many Feather Edge Boards Do I Need? Closeboard Fence (UK)
A feather edge (closeboard) fence is made of tapered boards that overlap. A 125 mm board with a 25 mm overlap covers 100 mm, so a metre needs 10 boards. 15 m of fence takes 158 boards, 6 posts, 15 arris rails and 5 gravel boards, with 5% extra on the boards. The feather edge fence calculator gives the list for your length.
Materials for common lengths
125 mm boards, 25 mm overlap, 5% extra, 3 m bays, three rails to a bay and a gravel board in each bay.
| Length of fence | Boards | Bays | Posts | Arris rails | Gravel boards |
|---|---|---|---|---|---|
| 3 m | 32 | 1 | 2 | 3 | 1 |
| 6 m | 63 | 2 | 3 | 6 | 2 |
| 9 m | 95 | 3 | 4 | 9 | 3 |
| 12 m | 126 | 4 | 5 | 12 | 4 |
| 15 m | 158 | 5 | 6 | 15 | 5 |
| 20 m | 210 | 7 | 8 | 21 | 7 |
| 30 m | 315 | 10 | 11 | 30 | 10 |
How the board width and the overlap change the count
For 15 m of fence with 5% extra:
| Board width | Overlap | Covers | Boards a metre | Boards in a bay | Boards for 15 m |
|---|---|---|---|---|---|
| 100 mm | 25 mm | 75 mm | 13.3 | 40 | 210 |
| 125 mm | 25 mm | 100 mm | 10.0 | 30 | 158 |
| 150 mm | 25 mm | 125 mm | 8.0 | 24 | 126 |
| 125 mm | 40 mm | 85 mm | 11.8 | 36 | 186 |
The parts of the fence
- Posts. Concrete or timber posts set 3 m apart, with one at each end of the run.
- Arris rails. Triangular rails fixed between the posts, three to a 1.8 m bay.
- Gravel board. A treated board along the ground, so the feather edge does not sit in the damp.
- Feather edge boards. Nailed to every rail, each overlapping the thin edge of the one before.
Before you build
- Check the height rules: a fence next to a highway or over 2 m high may need planning permission.
- Check who owns the boundary and tell the neighbour before you start.
- Set the first board plumb and keep a spacer for an even overlap.
- Treat the cut ends of the boards and the posts.
See also the fence panel calculator and the concrete calculator for the post holes. These are estimates: a bay that is not 3 m needs its own count.
Frequently asked questions
How many feather edge boards per metre?
With 125 mm boards and a 25 mm overlap, each board covers 100 mm, so 10 boards for each metre of fence.
How many boards in a 3 m bay?
30 boards for 125 mm boards and a 25 mm overlap, before the extra for cutting.
How many arris rails does a bay need?
Three for a 1.8 m (6 ft) fence, and two for a lower one: 15 rails for 5 bays.
How far apart are the posts?
Normally 3 m between the centres, which is the length of an arris rail. A closer spacing is stronger in exposed places.
Do I need a gravel board?
It is advised, because it keeps the bottom of the boards off the damp ground. It is 150 mm high, so cut the boards shorter to keep the fence at the height you want.
More guides
Tools & materials for this project
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Estimates only. Quantities depend on your materials, site and supplier. Confirm important numbers before you order, and check the Building Regulations and any planning rules for anything structural or close to a boundary.