Lightweight concrete fence posts

jellymid

We have 15 fence panels and posts to replace :eek: in the next fortnight. To save money, we need to do them ourselves, but the posts need to be 9 foot. The ordinary concrete ones are a bit heavy - even though I have been building my muscles up at the allotment and my husband has been force feeding me spinach!


Has anyone used the lightweight concrete ones - if so, which type and can you recommend them? If any one knows of a cheap source - I would be very grateful, too.


I have seen pressure treated wooden ones that are guaranteed for 15 years - but the guy in the timber yard reckoned they wouldn't last and the method of installation would be blamed.

Any advice gratefully received,

Thanks,

Al

jellymid

Shameless bump!

m_13

Supalite do recycled plastic fenceposts that they say are stronger than concrete. They are light, can be cut with a hand saw and are green as they are made from 90% recycled material.

Liniar also do light PVC fenceposts but don't mention if they are recycled.

They both seem to be cheaper than lightweight concrete posts.

jellymid

Thanks m_13. We thought these were the answer to our problems, so went to see some yesterday afternoon. Unfortunately they are a bit flexible and bend in the wind - good day to view yesterday! This means they squeak terribly as the wooden panel doesn't flex. The guy at the suppliers said that nothing they did seemed to stop the awful noise....hence we need to think again. If anyone has used these successfully, I would be delighted to hear from them as the look much easier to install. We do live in a windy spot, though. Thanks for your suggestion.

woodbutcher_2

Was going to recommend plastic posts too but if you are not keen and don't want concrete,then tanalised timber is the way to go.If you are worried about the bottoms rotting even though they are supposed to last 15 yrs,then you could put a coat of bitumen on the bottom 2 feet before sinking them.

jellymid

Thankyou both. I hadn't thought of bitumen. I have seen some lightweight concrete ones now, but they look very rough and sort of 'holey'. I think the wooden ones will look better. Is tanalised the same as pressure treated? We need 6 foot fence panels plus a gravel board - would you go for 4" by 4" or 3" by 3" posts?

woodbutcher_2

I always use tanalised 4"x4" posts for fencing and they need to be sunk 2 ft into the ground.

jellymid

I always use tanalised 4"x4" posts for fencing and they need to be sunk 2 ft into the ground

.

Thanks Woodbutcher. How long would you expect them to last...roughly?

artychoke

Generally, the bigger the section, the slower it should decay. (I'm a chartered architect by the way).

Tanalised is recommended but the bitumen is not so good as mosture will get in from above and stay there. All timber will decay eventually but you can slow this. This relies upon the timber staying toxic for as long as possible. This can be maintained best by concreting the posts in properly and redosing the accessible surfaces liberally. Try to keep long grass away too.

It's often reckoned to steep the ends (2ft at least) in creosote before concreting. Give all cut ends special treatment. Even put caps on the post tops. Farmers often use old sump oil at a push.

Good luck

artychoke

Sorry forgot to mention: Steep the post ends at least overnight, preferably longer. You'll be surprised at the amount "taken up" by the timber - the more the better.

woodbutcher_2

I used to use creosote for the post ends but you can't get it anymore.Sitting in cuprinol would do the same.Never thought about the effects of using bitumen.Noted.

4"x4" should last a long time.It doesn't sound much of a step up from 3"x3" but it is almost twice the area of wood.