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Fence Calculator

Panels, posts, gravel boards and concrete. Metric units, change any unit beside its field.

Measurements

%
Extra for cuts, breakage and spillage.

About this calculator

Everything for a garden fence: panels or feather edge boards, timber or concrete posts, gravel boards, caps, clips and post-mix.

How it’s calculated

Sections = (fence length − gate widths) ÷ post spacing, rounded up. Posts = sections + 1, plus one extra per gate. Feather edge boards are laid with about a 25% overlap. Posts are about 1.5 × the fence height so a third or more is buried.

Worked example

With these inputs:

Fence length
30 m
Fence height
1.8 m
Style
Panel fencing
Post spacing / panel width
1.83 m
Gates
1
Gate width
0.9 m
Post type
Timber
Gravel boards
Yes
Waste allowance
5%

the result is:

Panels and posts
18 posts
Sections / bays
16
Posts (incl. gate posts)
18

Tips from the trade

  • Set the end and corner posts first, then string a line for the rest.
  • Check boundary lines and any planning limits (2 m generally, 1 m next to a highway) before you build.
  • Gate posts take more load: go bigger and deeper.

Common questions

How many fence panels do I need?

Divide the fence length by the panel width (1.83 m) and round up. You need one more post than panels.

Results are estimates for planning and pricing. Check quantities against your drawings, the manufacturer’s data and the Building Regulations before ordering.