Fixing fence posts - suggestions wanted

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freeflow
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Fixing fence posts - suggestions wanted

Postby freeflow » 5 Apr 2015, 1:13pm

I have a 7ft tall panel fence in the back garden. It was put in new about 3 or 4 years ago. Recently I've discovered a distinct wobble when windy. On closer examination there are three loose posts. One has snapped at ground level, the other two appear to have either come loose in thier footing or have snapped below ground level. I don't want to remove the posts just support them in situ. They are not in metal holders, but have been concreted in with the concrete well below soil level.

Does anyone have any suggestions for the best way to support these posts?

Psamathe
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Re: Fixing fence posts - suggestions wanted

Postby Psamathe » 5 Apr 2015, 1:22pm

I am in pretty much the same position, except my problem fence posts are just in the groups (no cement).

As a short term fix (to keep the fence from falling over) I put in a sort of buttress post. Basically hammered a decent "peg" into the ground a couple of feet in from the fence and put a decent length of wood between peg in ground and top of fence post and screwed the buttress to both the ground peg and fence post. Makes everything stay up pending a decent repair.

Bit like http://www.cockeyed.com/lessons/fence/broken.php (not my site), but mine are steeper (which is probably worse.).

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cycleruk
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Re: Fixing fence posts - suggestions wanted

Postby cycleruk » 5 Apr 2015, 1:29pm

It is possible to dig out the wood part that is still in the concrete as I once (or twice) did and insert a new post.
I have also managed to fit a "metpost" in the concrete and re-use the old post. There are different styles of "metpost" that may suite to give a solution.
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Mick F
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Re: Fixing fence posts - suggestions wanted

Postby Mick F » 5 Apr 2015, 2:35pm

How long is the fence?
You say three posts are loose. How many more posts are there?
How are the others? With three gone, they'll be under extra strain, so I'd be very concerned that if three had gone, the others wouldn't be far behind.

I agree that a temporary solution is to buttress the three, but the only real solution is to replace them.
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Re: Fixing fence posts - suggestions wanted

Postby Vorpal » 5 Apr 2015, 3:02pm

You could try digging out around them, and 'wrapping' them in sheet metal. Stainless, or something like that which won't corrode too quickly is probably best. You might need to put some fresh concrete around the sheet metal.

But IMO, as Mick suggested, you will probably have a problem with others, soon, unless the situation or installation is different for the ones that have broken.

Wood should be protected, if possible from contact with the ground. It's best to have the concrete slightly above the surface of the soil, as it will sink with time. The posts should be encased in the concrete, not the ground. The contact with damp ground will cause rot, even in treated posts. Some woods are better than others, and they may require more than one type of treatment (e.g. against insects and rot).
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gaz
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Re: Fixing fence posts - suggestions wanted

Postby gaz » 5 Apr 2015, 3:26pm

Concrete repair spurs will probably work but you'll need to dig out the existing footings and make new ones for the spurs.

We had trouble with our fence last year (7 or 8 years old) and switched from my previous DIY efforts of wooden posts in metpost fittings with waney-lap panels, to slotted concrete posts installed in concrete footings with concrete gravel boards and stronger panels fitted by a local company. We expect those fittings to see us out and replacing the panels should be a DIY job when it becomes necessary.
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Re: Fixing fence posts - suggestions wanted

Postby rjb » 5 Apr 2015, 6:21pm

Next door neighbour had a couple of rotten wooden posts. The fence repair man left the concrete base in situ, removed the wooden post remnants by using a drill, then a hammer and chisel. He then just tapped the new post back in the same hole - job was a good un.
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Paulatic
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Re: Fixing fence posts - suggestions wanted

Postby Paulatic » 5 Apr 2015, 7:18pm

IMO posts/stobs always rot quicker when they are in concrete and always just above the concrete. Even quicker if the concrete is below ground level.
When in earth they usually rot in the first 6" under the surface. I now wrap a damp proof course or heavy duty plastic around them, at this point to extend their life.
I wouldn't waste time building buttresses, time would be better spent drilling and howking out the old bits and dropping new ones in.
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Re: Fixing fence posts - suggestions wanted

Postby Heltor Chasca » 6 Apr 2015, 8:31am

Hmm. Sorry I haven't got the most positive reply. I have done a lot of fences for clients over the years and this sounds chronic. If 3 out of (?) have gone it's likely there are other problems in the wings. Trouble is you'll only find out next winter. I would consider starting again.

Rather than a panel fence, consider a post and rail (3 of) fence with feather edge boards. You'll need 100mm posts for a fence this high, gravel boards along the bottom and a capping rail along the top. Postcrete rather than concrete too. I hope it works out ok...b

reohn2
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Re: Fixing fence posts - suggestions wanted

Postby reohn2 » 6 Apr 2015, 8:56am

rjb wrote:Next door neighbour had a couple of rotten wooden posts. The fence repair man left the concrete base in situ, removed the wooden post remnants by using a drill, then a hammer and chisel. He then just tapped the new post back in the same hole - job was a good un.


This is the answer,but make sure you use tanalised timber for the new post,and even then I'd further treat it with Cuprinol 5 star wood treatment or similar(but not a water based one) paying special attention to end grain by standing the new posts in it for a day or two.
When fitted I'd then mix some concrete(1/2/3(10mm stone) mix) and build up the existing footing around the post chamfering it so it sheds water away from the post base,but ensure you get a good key with it into the existing concrete.
The problem with wrapping posts in DPC or similar is that the DPC can act as a funnel channelling rain water to the post,it then holds it in place against the post like a little reservoir,not good IME.
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Re: Fixing fence posts - suggestions wanted

Postby garybaldy » 6 Apr 2015, 9:22am

I used to have 17 6'x6' waney lap panels with wooden gravel boards and wooden posts. They were OK for a few years but then they were in constant need of repair. I then replaced them all with concrete posts. Then instead of just one 1ft x 6ft concrete gravel boards I put 6 in each panel to make a 6ft wall of concrete. Expensive, but I haven't touched them in over 20 years. Also, as it is all concrete, it is classed as a wall, therefore covered by household insurance, a wooden fence is not, or at least wasn't when I had it done. My garden had an alley beside it and sometimes the yobs would kick the old panels in. I could claim on the insurance for that as it was vandalism, but I couldn't claim for storm damage, as it was a fence.

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Re: Fixing fence posts - suggestions wanted

Postby TonyR » 6 Apr 2015, 9:43am

gaz wrote:Concrete repair spurs will probably work but you'll need to dig out the existing footings and make new ones for the spurs.

We had trouble with our fence last year (7 or 8 years old) and switched from my previous DIY efforts of wooden posts in metpost fittings with waney-lap panels, to slotted concrete posts installed in concrete footings with concrete gravel boards and stronger panels fitted by a local company. We expect those fittings to see us out and replacing the panels should be a DIY job when it becomes necessary.


+1 for switching to concrete posts. A bit more expensive short term but saves a fortune in money and hassle long term because they don't rot and need replacing every few years. If you go for replacement wooden posts in the concrete holes then don't wrap them because that just traps the water against the wood. Let them dry out thoroughly and then paint them with a good bitumen waterproof paint over the bit that will be in the hole and for 6-12' above to keep the water out.

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Paulatic
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Re: Fixing fence posts - suggestions wanted

Postby Paulatic » 6 Apr 2015, 9:45am

reohn2 wrote:[

This is the answer,but make sure you use tanalised timber for the new post,and even then I'd further treat it with Cuprinol 5 star wood treatment or similar(but not a water based one) paying special attention to end grain by standing the new posts in it for a day or two.
When fitted I'd then mix some concrete(1/2/3(10mm stone) mix) and build up the existing footing around the post chamfering it so it sheds water away from the post base,but ensure you get a good key with it into the existing concrete.
The problem with wrapping posts in DPC or similar is that the DPC can act as a funnel channelling rain water to the post,it then holds it in place against the post like a little reservoir,not good IME.


Yes I'd agree with you there, in situations where I had to concrete I would chamfer up to the post.
Where there is no concrete though a DPC stops the contact with the first few inches of earth where all the bacteria and bugs which cause the rot live. Any rainwater will drain through.
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reohn2
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Re: Fixing fence posts - suggestions wanted

Postby reohn2 » 6 Apr 2015, 3:46pm

Paulatic wrote:
Yes I'd agree with you there, in situations where I had to concrete I would chamfer up to the post.
Where there is no concrete though a DPC stops the contact with the first few inches of earth where all the bacteria and bugs which cause the rot live. Any rainwater will drain through.


Tanalised timber and 5* wood treatment take care of the rot.The problems start when timber is constantly wet which breaks down the timber protection DPC IME holds wet in from the top rain running down the post.
I have over 120m of concrete fencing posts,no worries :) .
I also have 10 4x4 timber ones treated as above 10+ years still solid :)
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Re: Fixing fence posts - suggestions wanted

Postby pete75 » 6 Apr 2015, 3:52pm

If you use wooden posts again creosote them well. There's plenty of substitutes but where wood preservation is concerned accept no substitute......