Free · Material quantities

Board-on-Board Fence Pickets, Rails and Post Estimate

Board-on-Board Fence Pickets, Rails and Post Estimate. Use retained unit selectors and documented geometric or area assumptions to calculate quantities and supported inverse relationships.

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Calculator inputs

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How to use this calculator

  1. Enter the known values in the units shown. Results update as you type.
  2. Where results are editable, change one to solve backwards. Lock a value to hold it fixed.
  3. Use the worked example to check the method. Reset restores the starting fields.

Private by default

Inputs and results stay in this browser tab. Bookify does not upload or store the values you enter.

Formula and method

Example in initial displayed units: Fence length 10, Maximum post spacing 2.5, Fence height 2, Rails per section 2, Picket width 10, Picket overlap 2 gives Number of posts 5, Number of sections 4, Number of rails 8, Number of pickets 125, Post length 3.

sections = ceil(L/s); posts = sections+1; pickets = ceil((L−overlap)/(width−overlap)); rails = sections×rails per section

Worked example

Enter these known values and leave the other values blank.

Fence length
10 m
Maximum post spacing
2.5 m
Fence height
2 m
Rails per section
2
Picket width
10 cm
Picket overlap
2 cm
Number of posts
5
Number of sections
4
Post length
3 m
Number of rails
8
Number of pickets
125

Assumptions and limitations

  • Picket overlap must be smaller than picket width, and this untrimmed-board workflow requires fence length at least one picket width. The model counts a straight run with posts at both ends. It does not allocate boards or rails around gates and corners. Post length is exactly 1.5 times above-ground height, a planning ratio rather than a site-specific embedment or structural requirement.
  • Use compatible units and enough independent measurements. Clear unknown quantities before solving backward; a rounded count does not uniquely determine original dimensions. Display rounding does not represent measurement uncertainty.

Common questions

Is picket overlap the same as a gap between boards?

No. The entered overlap is subtracted from board width to obtain the incremental covered width. It must be positive and smaller than the board width in this workflow.

References

Require a positive incremental covered width and a fence run at least one full picket width for the retained overlap-count workflow.

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