Fence how-to · updated 27 August 2026

How to plan a wood fence

A fence is a linear run. Post spacing drives posts; picket width plus gap drives slats; gates are not deducted unless you subtract them. Post-hole concrete is bags per post, not a universal hole.

Run, spacing, extra end post

Measure the centreline. On-centre spacing includes the extra end member: panels = ceil(run ÷ spacing), posts = panels + 1, then add gate posts if the gate is extra. Forgetting the end post is the most common short count.

Gates: subtract gate width from the run or add the kit as its own line. Vinyl panel tools exclude gate kits for the same reason.

Pickets and post holes

Picket count uses width plus gap along the run, times rails high, with waste for cuts and slope. Gap changes the count as much as picket width.

Post-hole concrete uses hole diameter, post diameter and bags per post from the selected mix. Enter 0 post diameter to fill a sonotube solid.

Do it in order

  1. Measure the run and subtract gate openings you will not fence.
  2. Set on-centre spacing, then count posts as panels plus one.
  3. Size pickets from width plus gap, and post-hole bags from the selected mix.

Worked example — 96 ft run, 8 ft spacing, no gate

96 ÷ 8 = 12 panels, 13 posts. Rails are posts-driven (typically 2 or 3 per span). Pickets depend on the slat and gap you type, not on a universal 6 in board.

Planning boundary

This is a material list. It does not set property lines, wind design or a permitted height.

Does this set post depth?

No. Frost, soil and local embedment stay with the design and the AHJ.

What about vinyl or chain-link?

Use those calculators. Vinyl is panel width; chain-link is roll length plus line and terminal posts.

Are stain and hardware included?

No. They are separate estimate lines.