Fencing Calculator UK | How Many Fence Panels Do I Need?
Free UK fencing calculator. Work out how many fence panels, posts, gravel boards, postcrete bags and fixings you need for any garden fence.
How to Calculate Fencing Materials
Getting your fencing materials right before you start means fewer trips to the merchant and no awkward gaps at the end. This guide covers every component for standard UK garden fencing.
The Formulas
- Panels = Total fence length (m) ÷ panel width (1.83m) → round up
- Posts = Number of panels + 1 (plus extra for corners and ends)
- Gravel boards = Same number as panels
- Postcrete = 1 bag (20kg) per post (firm ground) or 2 bags (soft ground)
Standard UK Fence Panel Sizes
| Panel Type | Width | Heights Available |
|---|---|---|
| Lap panel | 1.83m (6ft) | 0.9m, 1.2m, 1.5m, 1.8m |
| Closeboard panel | 1.83m (6ft) | 0.9m, 1.2m, 1.5m, 1.8m |
| Hit & miss panel | 1.83m (6ft) | 0.9m, 1.2m, 1.5m, 1.8m |
| Trellis panel | 1.83m (6ft) | 0.3m, 0.6m, 0.9m, 1.2m, 1.8m |
| Featherboard (loose boards) | Individual 100mm boards | Cut to size |
Post Sizes
| Post Type | Cross Section | Lengths | Use |
|---|---|---|---|
| Standard timber | 75 × 75mm (3") | 1.8m, 2.4m, 3.0m | Lap/closeboard panels up to 1.2m |
| Heavy duty timber | 100 × 100mm (4") | 2.4m, 3.0m | Standard 1.8m fence panels |
| Extra heavy timber | 125 × 125mm (5") | 2.4m, 3.0m | Exposed sites, heavy panels |
| Concrete | 100 × 100mm | 1.8m, 2.4m, 2.7m | Long-life, slotted for panels |
Worked Example: 15m Garden Fence, 1.8m High Lap Panels
- Panels = 15 ÷ 1.83 = 8.2 → 9 panels (round up — you can cut the last panel)
- Posts = 9 + 1 = 10 posts (2.4m × 100mm timber)
- Gravel boards = 9 gravel boards (1.83m × 150mm × 22mm)
- Postcrete = 10 posts × 1 bag = 10 bags (20kg)
- Post caps = 10 post caps
- Panel clips = 2 per panel × 9 = 18 clips (or use screws)
- Arris rails (if closeboard) = 3 per bay × 9 = 27 rails
Corner and End Posts
Corners need special attention:
| Configuration | Extra Posts |
|---|---|
| Straight run | None — just count panels + 1 |
| 90° corner | 1 corner post (heavier gauge if possible) |
| End post (butting a wall) | Use a concrete fixing bolt or bracket |
| Gate post pair | 2 extra heavy posts (125mm minimum) |
Gate Sizing
| Gate Type | Standard Width | Post Requirement |
|---|---|---|
| Pedestrian gate | 0.9m (3ft) | 2 × 125mm posts |
| Wide pedestrian gate | 1.2m (4ft) | 2 × 125mm posts |
| Double/driveway gate | 2.4–3.6m | 2 × 150mm posts + centre drop bolt |
Closeboard (Featherboard) Fencing
For traditional closeboard fencing built on site from loose boards:
| Component | Per 1.83m Bay |
|---|---|
| Featherboard (100mm) | 20 boards (overlapping by 15mm) |
| Arris rails (3.6m) | 1.5 (3 rails per bay, each rail spans 2 bays) |
| Gravel board | 1 |
| Post | 1 (plus 1 extra to finish) |
| Capping rail | 1 × 1.83m length |
| Galvanised nails | 60 (3 per board) |
Concrete Post and Gravel Board System
Slotted concrete posts with concrete gravel boards last 25+ years:
| Component | Calculation |
|---|---|
| Slotted concrete posts (2.4m) | Panels + 1 |
| Concrete gravel boards (1.83m × 150mm) | Same as panels |
| Concrete post mix | 2 bags per post (heavier posts need more support) |
From Fencing Quantities to a Full Estimate
This calculator gives you material quantities. A full fencing estimate also includes:
- Labour (typically £30–50 per metre for supply and fit in 2026)
- Old fence removal and disposal
- Post hole digging (manual or with auger)
- Delivery charges
- Treatment/staining (first coat typically included; annual re-treatment recommended)
EasyEstimate’s fencing calculator covers all of these elements with live UK pricing — producing a complete material schedule and priced estimate.
Try the full fencing calculator free →
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Frequently Asked Questions
- How many fence panels do I need?
- Divide the total fence length by the panel width (standard 1.83m / 6ft). A 10m fence needs 10 ÷ 1.83 = 5.5 → round up to 6 panels. You need one more post than panels (7 posts for 6 panels).
- How deep should fence posts be in the ground?
- The standard rule is one-third of the total post length should be underground. For a 1.8m (6ft) fence, use 2.4m (8ft) posts with 600mm in the ground. Use postcrete or concrete to secure each post.
- How much postcrete per fence post?
- One 20kg bag of postcrete per post is standard for 100mm (4 inch) posts in firm ground. For 125mm posts, soft ground, or exposed sites, use 1.5–2 bags per post.
- How much does a new fence cost per metre in 2026?
- Typical UK costs for supply and fit: closeboard fencing £80–120/m, lap panel fencing £60–90/m, featherboard fencing £90–130/m. Prices include posts, panels, gravel boards, concrete and labour.
- Do I need gravel boards under fence panels?
- Gravel boards are strongly recommended. They sit between the ground and the fence panel, protecting the panel from ground moisture and rot. They're cheap to replace when they decay — far cheaper than replacing a full panel.
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