How many featheredge boards do I need per metre?

Using standard 100mm (4 inch) featheredge boards with a 25mm overlap, the effective width is 75mm. You need approximately 14 boards per metre run of fence. For 125mm boards (100mm effective), you need about 10 per metre. Always add 10% for wastage and damaged boards.

Is close board fencing better than fence panels?

Close board (featheredge) fencing is stronger and longer-lasting than panel fencing. Individual boards can be replaced without removing whole sections. It handles wind better as air passes between slight gaps. It's more expensive to install but is the professional choice for permanent boundaries.

How many arris rails do I need?

Use 2 arris rails for fences up to 1.2m (4ft) tall, and 3 arris rails for fences 1.5m (5ft) and above. Rails should be evenly spaced: for a 1.8m fence with 3 rails, position them at approximately 300mm, 900mm, and 1500mm from ground level.

Do I need gravel boards for close board fencing?

Yes, gravel boards are strongly recommended. They sit between the posts at ground level, keeping the featheredge boards off the damp ground. This prevents rot and extends the fence's life significantly. They're inexpensive and easy to replace if they rot — much cheaper than replacing fence boards.

What size posts for close board fencing?

Standard fence posts for close board fencing are 75mm x 75mm (3 x 3 inch) or 100mm x 100mm (4 x 4 inch) for taller fences. Post length should be fence height plus 600mm (2ft) for burying in the ground. For a 1.8m fence, use 2.4m posts. Always use treated (tanalised) timber.

Close Board Fencing Calculator — Featheredge Slats & Materials

Calculate individual featheredge boards, posts, arris rails and fixings for close board fencing. UK standard sizes.

Total Fence Length

Total run of fencing

Fence Height

Featheredge Board Width

Post Spacing

Include wastage allowance

Adds 10% for damaged/split boards

Wastage Percentage

10% is standard for featheredge boards

Include gravel boards

Prevents featheredge boards rotting at ground level

Include capping rail

Protective cap along the top of the fence

Include Postcrete

Fast-set concrete for fence posts

Price Per Slat (optional)

Price per individual featheredge board

How We Calculate This

Our close board fencing calculator works out every component needed for featheredge fencing, from individual slats to posts, arris rails, gravel boards and fixings.

The formulas

Posts = (Total length ÷ Post spacing) + 1
Slats per bay = Bay width ÷ (Slat width - 25mm overlap)
Total slats = Slats per bay × Number of bays × Wastage factor
Arris rails = Rails per bay (2 or 3) × Number of bays

Key dimensions

Featheredge overlap: 25mm minimum
Post spacing: 2.4m (8ft) standard, max 3.0m
Post depth: 600mm (2ft) in ground
Arris rails: 2 for fences to 1.2m, 3 for 1.5m+
Gravel boards: 150mm × 22mm, set 25-50mm off ground

Frequently Asked Questions

Related Calculators

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Concrete for Fence Posts Calculator

Calculate postcrete or concrete needed to set fence posts.

Gravel Board Calculator

Calculate gravel boards and clips needed for your fence run.

Trellis Calculator

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Last updated: February 2026

All calculations are estimates. Verify with your supplier.