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Fence Calculator

Work out fence panels, posts, gravel boards, postcrete and fixings for any UK run length.

Inputs

16 advanced inputs hidden. Switch to Advanced to fine-tune.

Confidencehigh· 88Complexitylow· 28

Order what you need for this job

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Run length
12m
Feather-edge boards
120
Arris rails
21
Concrete posts
8
Capping rail (3 m)
4
Post caps
8
Concrete gravel boards
7
Gravel-board clip packs
2
Postcrete bags
16
Fixings packs
3
Post length (min)
2,400mm
Post hole depth
600mm

Heads-up: Closeboard (feather-edge) fencing is built on site from posts, rails, gravel boards and individual feather-edge boards — not panels. Expect 3 rails per bay over 1.8 m high. Why it matters: Boundary fences over 2 m need planning permission — even in your own garden.

Your fence, drawn

Each elevation recomputes from the run lengths, heights, gravel-board decision and any retained soil.

Run 1 · Closeboard12 m · 1800 mm high · 7 bays
ground level+1 more bays1800600 deep

Concrete gravel board — At 1.8 m+ the run is exposed to more wind and ground moisture — a concrete gravel board adds rigidity and longevity. Posts ≈ every 1.71 m, set 600 mm deep.

Before you order — check these

Underground services check recommended before excavation. Use a CAT scanner or contact utility providers.

Why it matters: Gas, electric, water and telecoms cables are often shallower than expected — HSE guidance HSG47 mandates a safe-digging process.

If ignored: Striking a live service can cause serious injury, supply outages affecting the whole street, and personal liability for repair costs.

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Essentials for this job

Quantities include a ~10% waste allowance. Guide prices are indicative UK ranges (materials only, inc. VAT) — always confirm with the supplier before ordering.

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Ad · Some links are sponsored. We may earn a small commission at no extra cost to you. Suppliers are chosen for fit, not commission.

This app provides general UK guidance and material estimates only. It is not legal, planning, engineering or building-control advice. Always confirm requirements with your local planning authority, building control, utility providers, manufacturers or qualified professionals.

How to work out fencing materials

Start with the total run length of your fence. Divide it by the panel width — 1.83 m for a standard UK panel — to get the number of panels, then add one post per panel plus a final post to close the run. The calculator above also sizes gravel boards, postcrete and fixings so nothing is missed when you order.

Fencing spec guide (UK)

ItemGuide
Standard panel width1.83 m (6 ft)
Post spacing1.83 m centres
Post depth (1.8 m fence)~600 mm
Postcrete per post1–2 × 20 kg bags

Fences over 2 m (or over 1 m next to a vehicle highway) usually need planning permission. Check local rules and any boundary agreements before starting.

Pricing a full boundary job?

Set out the line and levels, take off every material and build a quote.

Open Setting Out & Levels

Frequently asked questions

How many fence panels and posts do I need?
Divide your run length by the panel width (1.83 m for a standard UK panel) to get the number of panels, then add one post per panel plus one to finish the run. The calculator above works this out and includes gravel boards, postcrete and fixings.
How far apart should fence posts be?
Set posts at the panel width — 1.83 m centres for standard 6 ft panels. Keep spacing consistent so panels drop straight into the post slots or clip neatly to the posts without gaps.
How much postcrete per fence post?
Allow one to two 20 kg bags of postcrete per post, depending on post size and hole depth. The calculator estimates bags from your post count so you can order in one go.
How deep should fence posts be set?
As a rule of thumb, set posts to a depth of about a quarter to a third of the above-ground height — typically 600 mm for a 1.8 m fence. Dig deeper for taller fences or exposed, windy sites.
Do I need planning permission for a fence?
In most of the UK you can build a fence up to 2 m high without planning permission, or up to 1 m if it adjoins a highway used by vehicles. Always check local rules and any conservation-area restrictions before you start.

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