Postcrete and a fence post support.

robj20

robj20

robj20

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Anyone used postcrete with one of these Vs traditional concrete, is rather it set fast.

www.screwfix.com

Sabrefix Concrete-In Post Supports 100 x 100mm 2 Pack - Screwfix

Order online at Screwfix.com. Use in hard standing areas or where ground conditions prevent the use of post support spikes. Ideal for carports, pergolas, raised decks and general fencing. Mild steel base, galvanised and powder-coated. FREE next day delivery available, free collection in 1 minute.
www.screwfix.com www.screwfix.com

It's a tight fit hole so wondering if there is time to mix it up get it all straight before it sets.
 
Everyone uses postcrete these days, they're even building walls with it in the other thread. Seriously though, it'll be fine it doesn't set in 1 minute you get a bit of play time to get it level. You just dump it in the hole and add water.
 
oddly its the opposite on the ones I have used recently which caught me out.

Dig hole, fill with water to a certain level (50% from memory) pour postcrete into hole
Not sure if they changed it or if we have always done it wrong
  • Ready-to-use with no mixing needed simply pour from the bag into the post hole containing the fence post and water
 
If you follow the official postcrete guidelines you should be fine.
Fit your post support, fill with some water, push some postcrete in, top up water a bit, more postcrete, repeat

It does set quite quickly, like 5 minutes but if your constantly adding that should be fine.

My concern with what your doing if access is really limited is making sure the hole is properly filled and not just round the edges.

Sometimes those sort of supports have some holes inside to assist with drainage. You may be able to pour the postcrete down the middle.
Could even be worth considering drilling one or expanding one so you can take that approach.
 
Mercenary Keyboard Warrior said:
If you follow the official postcrete guidelines you should be fine.
Fit your post support, fill with some water, push some postcrete in, top up water a bit, more postcrete, repeat

It does set quite quickly, like 5 minutes but if your constantly adding that should be fine.

My concern with what your doing if access is really limited is making sure the hole is properly filled and not just round the edges.

Sometimes those sort of supports have some holes inside to assist with drainage. You may be able to pour the postcrete down the middle.
Could even be worth considering drilling one or expanding one so you can take that approach.
Click to expand...
Exactly, I'll have to see if I can also enlarge the hole it's going in.
 
robj20 said:
Yes just a wooden post shoved in the ground which overtime has come loose and rotted away.
It's at the edge of the patio so might not be easy to make the hole bigger.
Click to expand...

www.screwfix.com

Sabrefix Fence Repair Spike 75 x 75mm 2 Pack - Screwfix

Order online at Screwfix.com. Solves the problem of rotted posts that have broken off at ground level but are in a sound concrete base. Made from mild steel, galvanised and powder-coated for long life. FREE next day delivery available, free collection in 1 minute.
www.screwfix.com www.screwfix.com

Much easier

Sorry realise you had 100mm

www.toolstation.com

Drive-in Repair Spike

For replacement of rotted posts broken at ground level. Powder coated mild steel for protection. Can be used with the drive in tool (code 39219). Lengths are spike lengths.
www.toolstation.com www.toolstation.com
 
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Mercenary Keyboard Warrior said:
www.screwfix.com

Sabrefix Fence Repair Spike 75 x 75mm 2 Pack - Screwfix

Order online at Screwfix.com. Solves the problem of rotted posts that have broken off at ground level but are in a sound concrete base. Made from mild steel, galvanised and powder-coated for long life. FREE next day delivery available, free collection in 1 minute.
www.screwfix.com www.screwfix.com

Much easier
Click to expand...
Not really. It's not in soil, it's at the edge of my patio. What would I hammer the spike into?
All around the hole is either a concrete wall, stone or patio.
 
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robj20 said:
Not really. It's not in soil, it's at the edge of my patio. What would I hammer the spike into?
All around the hole is either a concrete wall, stone or patio.
Click to expand...

Thats what they do.
They slip round the outside of the old post and you hammer them down inside the hole.
They rely on the old concrete to hold them in place.

 
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Mercenary Keyboard Warrior said:
Thats what they do.
They slip round the outside of the old post and you hammer them down inside the hole.
They rely on the old concrete to hold them in place.

Click to expand...
I think you're misunderstanding what in trying to do and what I already have.
It's just a hole let's say 120x120mm with a wooden post in it. I can lift it out.

I'm going to replace it with a properly done concreted in support which the new post can screw into.
I imagine the post when first put in was fairly solid but the wind was blowing it back and forth which has made the hole bigger.
 
Well when you said it was a tight fit I had assumed it was a tight fit not 2cm gaps.
You can get cement in place supports that would be easier to set in place than that one.

I think it it was me with an oversize hole :D I would use a normal 600mm or so hammer in job, leave it slightly proud, fill round it with postcrete and then wack it down to level afterwards
If the concrete has been damaged by a post its probably not much good
 
I've only once used postcrete and never again. Call me old fashioned, but I prefer the traditional concrete approach. Put in the first post, use some timber to set it straight and let it dry overnight. Then the following day you add another post and panel one at a time. Replacing the earth as you go, that's largely responsible for holding everything in place until it sets. Use timber braces as you think necessary. It's all very easy.
Metal supports are expensive and largely unnecessary. A 4" post will outlast a metal support (which will just rust). I put in standard cheap 4" posts god knows how many years ago and they are still going strong. Even in the worse soil if you coat the ends in bitumin paint they will last pretty much forever, unlike 3" posts which rot through in no time at all.
 
The first post is easy as that's just bolted to the garage wall with some brackets, the second part is this one then the third one I can bolt to a 2ft high wall, after that there are concrete posts.

So it's only the one post I need to deal with. I think I'll go with the approach of putting postcrete in until the support sits at the height I want, high enough that water can't sit in the bottom of it. Then fill it from there then add water. I can loosely fit the first panel to give me a level for the post. Then leave it for an hour before fixing the panels.

The hole obviously won't be dry so as long as I've got 10mins or so I think that'll be long enough.
 
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Those repair spikes/supports are all rubbish. Any movement from the fence just gets worst quickly. The bolts loosen then the metal starts to cut into the post letting rot start even though they are out of the ground.
If you have a hole already but you dont think its wide enough to get enough postfix in and around a post you could try undercutting the paving/concrete making a larger void below ground level. Then you'll be able to get you postfix in. You dont have to fill to the hole completely straight away, just enough so it will grab the post so you can plumb it.
A picture would help.
/Just seen your new post
 
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Postcrete/postmix is great - easily get a few minutes working time. I did a row of posts that blew down in the storm we had last year. My process was old post out, fill hole half full with water, post in hole, postmix on top. Helps to have spirit level and some scraps of wood to screw in as temporary supports nearby before you pour the mix in, but easily enough time to make sure it's plumb before the concrete goes off.

If you're hoping it'll last _years_, I'd recommend checking out the concrete fence post spars. Doesn't matter how well you treat wooden posts, they're not supposed to sit in water and will eventually rot. Might have more luck with the metal brackets linked above, but I've seen more than a few rust through.
 
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Hey guys, sorry to piggyback on this thread but I'm in a very similar situation. A metal gate post has snapped and left the bottom bit still in the ground and concreted in. It's basically left a hollow section of 80x80 and about 200mm deep.

I was thinking of putting a metal support into the hole, cementing it in and using a timber post as a replacement (can tie into the fence).

which of these products do you think is a stronger solution?

1) a metal u support bracket with 200mm rebar
2) a fencemate concrete in swift clamp

Thanks for reading!
 
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