How to Estimate Fencing Materials (Posts, Strainers, Stays and Wire)

← Farm & Yard guides

A plain wire, barbed wire or mesh fence is mostly the same few parts, repeated. Count the sides and corners first, and the rest follows.

1. The parts

• Line posts: star pickets or timber posts along the run, holding the wires up.
• Strainer posts: the heavy posts the wires are tensioned against. You need them at every corner, at each end of an open line, on both sides of each gate, and partway along very long straight runs.
• Stays: the braces that stop a strainer being pulled over. You need one for each direction a strainer is pulled.
• Wire or mesh: plain wire, barbed wire, or rolls of mesh or netting.

2. Step 1: list the sides

Walk the fence and write down each straight side and its length. Each change of direction is a corner, and each corner needs a strainer.

Say whether the fence is a closed paddock (it joins up all round) or an open line (it has two ends).

3. Step 2: line posts

For each side, divide the length by the post spacing and round up. That gives the number of gaps. The posts in between are one fewer, because the strainers sit at the ends.

The calculator starts at 4 m spacing. That's a common starting point, not a rule. Use your own plan or local practice.

4. Step 3: strainers and stays

Strainers = corners (or corners and ends) + extra strainers on long runs + 2 for each gate.

• Long runs: an extra strainer goes in when a straight side is longer than the longest strain your wire allows. The calculator starts at 200 m, but check the wire maker's guide.

Stays are counted in the calculator like this:

• 2 per corner on a closed paddock;
• 2 per corner and 1 per end on an open line;
• 2 for each long-run strainer;
• 1 for each gate post.

5. Step 4: wire and mesh

• Take the gate openings off the total length to get the wire run.
• Wire = wire run × number of wire lines × (1 + waste). The calculator adds 5% for wrapping strainers, joins and offcuts.
• Mesh = wire run × (1 + waste), in rolls of the length on the label.

6. Worked example: a 200 m × 100 m paddock

The calculator's starting example: four sides (200, 100, 200 and 100 m), closed, one 3.6 m gate, line posts every 4 m, an extra strainer only past 200 m, four plain or barbed wire lines, 500 m rolls and 5% waste.

Gate openings aren't taken off the line-post count, so you may have one or two posts spare.

7. Before you buy

• Walk the line. Hills, gullies, soft ground and creek crossings need extra posts and strainers.
• Check roll lengths. Wire and mesh come in many roll lengths, so read the label.
• Strainer assemblies: stay lengths, post depth and wire tension should follow the wire and post makers' instructions or your local practice.
• Before you dig: contact Before You Dig Australia (1100.com.au) before driving posts or digging holes.
• Boundary fences: check the dividing fence rules with your council or state before building on a boundary.

8. Common mistakes

• Forgetting the strainers at gates.
• Missing the extra strainer on a very long straight run.
• Counting the wire on the full length, including gate openings (or forgetting waste for tie-offs).
• Not walking the line before ordering.
• Driving posts without a Before You Dig check.

9. Quick summary

• List each straight side, and note whether it's a closed paddock or an open line.
• Line posts: length ÷ spacing, rounded up, minus one per run.
• Strainers: corners or ends, long runs, and 2 per gate.
• Wire: (length − gates) × lines × a little extra.
• Walk the line and call Before You Dig first.

Try it with your own fence: Fencing Materials Calculator. Adding a hot wire? See Planning an Electric Fence.

General information only. Follow the wire and post makers' instructions and local practice.