The posts hold the fence up – so don't skimp on them. Here's how many you'll need.
At 200 cm post centres, plan for 1 post per 2 metres of fence + 1 extra at the end. For a 12 m fence that's 7 posts.
Post count = (fence length ÷ post spacing) + 1. The extra post at the end is what holds the final bay up.
180–200 cm post spacing is standard. For a stiffer fence, drop to 150 cm.
Each post needs to be about fence height + 60–80 cm so you can sink it or anchor it.
12 m ÷ 2 m + 1 = 7 posts. Each post should be 180 + 70 = 250 cm tall to leave 70 cm in the ground. Buy 7 × 250 cm posts in 9 × 9 cm pressure-treated timber.
Enter your fence length and height – the calculator works out posts, boards and screws.
200 cm is normal for a stable fence. Wider spacings need beefier posts or extra rails.
Yes, or use a metal post anchor. Pressure-treated timber straight in soil rots quickly.
At least 60 cm for a 180 cm fence. Soft ground or windy sites: 80 cm.
9 × 9 cm for most fences. Step up to 12 × 12 cm for tall fences (over 200 cm) and at corners and gate posts.
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