One of the most common fencing questions we get at the Gympie store is a simple one: how far apart should I put my fence posts? There's no single magic number — the right spacing depends on what you're fencing, the country you're fencing across, and how hard your stock push. Here's a practical rundown to help you plan a straight, tight, long-lasting fence.
Two jobs, two types of post
Before you measure anything, it helps to know that a fence has two very different kinds of post doing two different jobs.
Strainer posts are the anchors. They hold the strain of the wire and keep the whole fence tight and upright. They go at the ends, corners, gateways, and anywhere the fence changes direction or drops through a gully or over a rise.
Line posts (star pickets) sit between the strainers. Their job is to carry the line of wires at the right height and add support — not to take the full strain. Because they do different jobs, you space them differently.
What decides your line post (picket) spacing
Three things move the number up or down:
Number of wires. A heavy 9–12 wire fence carries a lot more weight than a 4-wire fence, so it needs pickets closer together for support.
Stock size and pressure. Cattle lean and push, so posts go closer together. Sheep and goats put less pressure on a fence, so you can stretch the spacing out a bit further.
Terrain. On flat country you can space pickets wider. Through hills and undulating ground you'll want more posts so the fence follows the contour — and a strainer at the top of each rise and the bottom of each gully.
Rough spacing guide
Use these as a starting point and adjust for your own conditions:
| Situation | Typical picket spacing |
|---|---|
| Crop / exclusion fence, flat, no stock | ~5 m (tighten to ~4 m for heavy pig or roo pressure) |
| Sheep, flat or hilly | ~4 m |
| Cattle, flat ground | ~4 m (add inline strainers for rowdy cattle) |
| Cattle, hilly ground | ~3 m |
| Rural roadside boundary (QLD) | ~4 m with 4 wires — check current local road specs |
Roadside and boundary fences often have set requirements, so always check your local council and rural road rules before you start.
Where your strainer posts go
Get the strainers right and the rest of the fence falls into place. Put a strainer at:
every end and corner; both sides of every gateway; any real change of direction; the top of a hill and the bottom of a gully (a picket in those spots will pull straight out or get driven into the ground under strain — a strainer won't).
On a long straight run with no corners or gates, drop in an inline strainer roughly every 100 m — and bring them closer where cattle put extra pressure on the fence, like a laneway into the yards. For strength, we recommend steel strainers of 80NB (89 mm OD) or heavier; the thicker the wall, the more strain it holds and the further apart they can go. For a big change in direction on a high-tension fence, add a stay to keep the strainer upright.
Ground conditions: depth beats quantity
In soft going, adding more posts isn't the answer — depth is. In black soil or clay, use longer posts set deep (or a drive-in end assembly that grips more ground). In sand, set your posts deeper rather than adding more strainers. Rocky ground is harder to drive, but the rock actually grips the post and gives you extra hold.
Four quick tips for a fence you only build once
1. Strainers first. Mark your ends, corners, gateways and any change in direction or slope, and set your strainers before anything else. Where you can, make a gate post double as a corner.
2. Space pickets evenly. Even spacing between strainers gives even support — and it looks the part too.
3. Double-check before you strain up. It's quick to add a post before the wire's on and a real headache after. Do it once, do it right.
4. Look over the fence. On a boundary, match your build to your neighbour's stock. A light 3-wire fence next to a mob of Brahmans will give you grief down the track.
Need a hand planning your fence?
We carry star pickets, strainer posts, wire, end assemblies and all the fittings in stock at Gympie, and we're happy to help you work out what you need. Call the team on (07) 5482 1692 or browse our Fencing & Gates range online.
These figures are a general guide only. Always allow for your own soil, stock, wire type and any council or road-authority requirements when planning a fence.