Wooden fence posts - how long should they last?

SKSH

Hi
I’d really appreciate some advice if anyone can help - I had some wooden fencing (ten 5ft close board panels with trellis) put in back in early 2014 and it seems the fence posts for at least half of them have now rotted and need replacing. I’m sure they should have lasted longer than this - any advice appreciated. The guy who originally put them in says they typically ‘go’ between 5-8 years and is recommending I replace with concrete posts at considerable extra cost. Would be great to hear from anyone who knows more about this then me!
Thanks, Sarah

Davesnave

Longevity depends on how well the posts and panels are protected with pressure treatment and how wet and aggressive the soil is. Even the type of nails used make a difference too.

As an example fencing, bought from Jacksons was up to 20 years old when we left our last house and the posts/panels were all still fine without any sort of treatment.

Some cheaper panels, bought from Homebase for an internal division within the garden, failed after about 6 or 7 years.

Here, at our new property, about 10% of our farmers' fencing stakes with a 15 year guarantee failed in 7 or 8 years. The local ones with no guarantee began to go at 5 years. Thinner stakes made by Jacksons that just mark out our drive are all still sound, with no failures.

If you look at Jackson's web site you'll see they guarantee a service life of 25 years. My experience bears this out. Their prices are generally higher, but they seem to have cracked the problem of rotting. Whether others have, I can't say, but you probably won't find quality posts in the usual consumer outlets/DIY sheds..

molerat

I am just replacing some of mine that were put in in 1996.

snowcat75

Davesnave wrote: »

Longevity depends on how well the posts and panels are protected with pressure treatment and how wet and aggressive the soil is. Even the type of nails used make a difference too.

As an example fencing, bought from Jacksons was up to 20 years old when we left our last house and the posts/panels were all still fine without any sort of treatment.

Some cheaper panels, bought from Homebase for an internal division within the garden, failed after about 6 or 7 years.

Here, at our new property, about 10% of our farmers' fencing stakes with a 15 year guarantee failed in 7 or 8 years. The local ones with no guarantee began to go at 5 years. Thinner stakes made by Jacksons that just mark out our drive are all still sound, with no failures.

If you look at Jackson's web site you'll see they guarantee a service life of 25 years. My experience bears this out. Their prices are generally higher, but they seem to have cracked the problem of rotting. Whether others have, I can't say, but you probably won't find quality posts in the usual consumer outlets/DIY sheds..

However since the discontinuation of oil based treatments over the last few years softwood posts simply do not last.


A colleague of mine is fencing contractor and puts in miles upon miles of stock fencing much of it for water authority's and the MOD, replacement used to be 15-20 years excluding damage etc, with the water based treatments (which they all are) that timescale is cut in half.


The only new timber I will bury in the ground is chestnut, overwise its steel or concreate.

Pressure treatment is only as good as the available product, so irrespective of brand, and believe me my colleague is an anorak on fencing will have tried them all they will all be doomed to fail so much quicker than they used to.

getmore4less

100mm at the bottom of our garden sill OK from around 1994.
Developer installed cose board most of the boards still OK barge boards bending where soil on one side only.

Most of the 70mm for the side fences with panels have been replaced at least once some twice, they rot its the winds that finally kill them.
The 70mm set into metal supports for a pagoda are still OK from 1996.

Concrete are not that much more expensive.

You could look at metal repair kits using the same post.

no1catman

I think the stress they are subject will be a factor.
We had fencing put in when we moved in in 2007 with 8.5 fence panels.
It didn't take long for a storm to wreck havoc, requiring a new panel, by the time Storm Imogen came along probably half had been replaced! Imogen took out a couple of panels and at least one post - rotten.
Had it completely replaced by 'feather-edged' fencing, the new posts were fixed at a deeper level than the previous, and with the feather-edge style the posts are subject (IMHO) to less stress -never had any problems since.

The other option, is to embed a metpost stake in the ground, and slot your post into the metpost - much less contact between wood and wet ground.
HTHs.

knightstyle

When my DD's fence posts broke at ground level I got some concrete "repair spur" posts and put them in, hard work chiselling some of the old concrete away but they work really well and you do not disturb the existing fencing.

Davesnave

snowcat75 wrote: »

A colleague of mine is fencing contractor and puts in miles upon miles of stock fencing much of it for water authority's and the MOD, replacement used to be 15-20 years excluding damage etc, with the water based treatments (which they all are) that timescale is cut in half.

Yes, I said that was my sort of experience with '15 year guaranteed' stock fencing.


However, my Jacksons posts here are 10 years old and all still fine. Their guarantee remains at 25 years too, so whatever process they're using seems on this limited amount of evidence to still be working better than others' processes.

couriervanman

Put new fence in front & back garden back in 2001 the posts came pressure treated but i also soaked the bottom 2 feet of all posts in a wood treatment/protector overnight.Whilst planting some new shrubs a couple of weeks ago i dug down a few inches on a couple of posts and they are rock solid.
Next door neighbours also did his two fences 3 years later 2004 with posts from same supplier and stuck them straight in (he's a so called diy expert with a tool for every job and thought it was a bit overkill soaking my posts........he replaced most of his posts in 2011 and again in 2018 ignoring my advice to soak them in treatment saying its not needed :rotfl:

tori.k

We've gone overkill on ours, Husband really doesn't want to replace the posts in his lifetime :rotfl: class 5 fence post soaked in cerocote overnight fitted with a post collar and set in a concrete pad troweled for run off, I pity the poor beggar that has to eventually dig it up.

roddydogs

If I was doing my own fencing I would get 2 thick rubble sacks per post and put the post in those, and obviously cut off the surplus. But youll never get an istaller to do this as he wants repeat orders.