Guide

Concrete or timber posts — which to use where

Concrete posts outlast timber in ground contact and will not rot at the base, which is where a timber post almost always fails. They are heavier to handle and cost more per post, but a slotted concrete post takes a panel straight in with no fixings.

Timber posts are lighter, cheaper and easier to cut on site, and they look right where the fence is meant to read as timber throughout.

Shop concrete posts Shop timber

The short version

Concrete where the ground is wet or the run is long. Timber where looks matter and the ground drains.

Mixing them along one run is fine — concrete at the corners and any straining post, timber in between.

Side by side

CONCRETE POSTS

Life in ground contact Decades — it does not rot

Weight per 8ft post Roughly 40kg. A two-person lift

Fixing panels Slots. The panel drops straight in

Cutting on site Not practical. Buy the right length

Cost per post Higher up front, lower over time

Best for Wet ground, long runs, corners and straining posts

TIMBER POSTS

Life in ground contact Governed by the base — use UC4 and a gravel board

Weight per 8ft post Roughly 12kg. One person

Fixing panels Screwed or nailed. Any panel, any position

Cutting on site Easy — seal the cut end before it goes in

Cost per post Lower up front

Best for Free-draining ground, shorter runs, a timber look throughout

How to choose

Three questions, in order

Most of the concrete-versus-timber argument disappears once you have answered these. Work down the list and the answer is usually obvious.

Does the ground hold water? Stand on it after heavy rain. If it stays soft, the base of a timber post spends winter wet and that is what finishes it. Concrete does not care.

How long is the run? A long run takes more wind load, and every post is carrying it. Concrete at the corners and straining points stiffens the whole fence, whatever you use in between.

Does it have to look like timber? This is a fair reason on its own. A timber post on a garden boundary reads as one fence rather than a panel bolted between two grey uprights.

Quick answers

The things people ask us most — you might not need to message at all.

Can I mix concrete and timber posts in one run?

Yes, and it is often the sensible answer. Concrete at the ends, the corners and any straining post, timber for the intermediates. You get the stiffness where it matters without paying for it along the whole run.

How deep do posts go in?

The usual rule is a quarter of the finished height in the ground. A 6ft fence wants roughly 600mm below ground, which is why an 8ft post is the standard buy for a 6ft panel.

Do concrete posts need concreting in?

Yes. Their weight helps but it is the collar of concrete or post mix that holds them. Set them plumb and let them go off before you load a panel in.

Will a timber post really rot?

Not automatically. Pressure treated to UC4, set clear of standing water, with a gravel board keeping soil off the panel, a timber post lasts a long time. What kills them is a cut end put straight in the ground unsealed.

Can I replace a rotten timber post with concrete?

You can, but the panel fixing changes — a slotted concrete post needs the panel to slide down from above, which usually means lifting the neighbouring panels too. A concrete repair spur is often the easier fix.

Which is cheaper overall?

Timber is cheaper to buy. Concrete is usually cheaper over the life of the fence, because the second time you replace a post you also pay for the labour and the panel you damaged getting it out.