Installing fence post in existing hole

[Notreallymeeither]

Hi all

Weekend job is to install new fence panels and posts.

Hopefully the image below shows the problem.

The existing posts had rotted in the concrete and so they pulled out easily and left me with a perfect post-sized hole in the concrete ground to install the new posts.

Ive tried to push the posts in a bit but can’t get the posts deep enough and they are wobbly.

What’s the best way to do this to get a nice solid post. Am I best off digging out one half of the hole and then slotting the post in and postcreting it in place? Or should I whack the post in with a big sledge hammer as deep as I can?

Thanks

[Gary C]

Is there still some of the post in the hole preventing full insertion ?

If not, just put it in, then hammer some wedges in between the post and the hole.

If there is and you just cant really get enough of the post into the hole, then its concrete digging out time

[Clifford Chambers]

Notreallymeeither said:

Hi all

Weekend job is to install new fence panels and posts.

Hopefully the image below shows the problem.

The existing posts had rotted in the concrete and so they pulled out easily and left me with a perfect post-sized hole in the concrete ground to install the new posts.

Ive tried to push the posts in a bit but can’t get the posts deep enough and they are wobbly.

What’s the best way to do this to get a nice solid post. Am I best off digging out one half of the hole and then slotting the post in and postcreting it in place? Or should I whack the post in with a big sledge hammer as deep as I can?

Thanks

I think option 1

A, sledge hammer will just damage/split the post and probably not get in far enough. If you must bash it use a post driver, option 1 will be more satisfactory though.

[Doofus]

If there's a rotten old post in the hole you could attack it with a long drill bit to break it up, then fill the hole with water to make the bits of wood float to the top so you can get rid of them.

[Notreallymeeither]

Gary C said:

Is there still some of the post in the hole preventing full insertion ?

If not, just put it in, then hammer some wedges in between the post and the hole.

If there is and you just cant really get enough of the post into the hole, then its concrete digging out time

Thanks. I think I’ve got most of the old post out but suspect there is some soil etc at the bottom. Might have to put my daughter to work getting her hand down the hole.

But yes I suspect it is concrete digging time.....

[Jaska]

Could you set the old post on fire, let it all burn up?

[Notreallymeeither]

Thanks all for the replies. Looks like concrete digging out time (I want the fence to be really strong and not wobbly)

Looks like time for the old Titan SDS and my angle grinder.

[KTMsm]

FiL was a fencer - he made short work of similar in my garden

He used a 6' steel spike to crack the conc in half (surprisingly easy) then re concreted using the suitable sized chunks in the mix

He was 70 at the time

[Notreallymeeither]

KTMsm said:

FiL was a fencer - he made short work of similar in my garden

He used a 6' steel spike to crack the conc in half (surprisingly easy) then re concreted using the suitable sized chunks in the mix

He was 70 at the time

Thanks. Did he use the 6’ spike as a lever to break up half of the hole (or did he just whack the concrete with the spike until it broke up?)

[KTMsm]

Notreallymeeither said:

Thanks. Did he use the 6’ spike as a lever to break up half of the hole (or did he just whack the concrete with the spike until it broke up?)

Hit it, you could do the same with a pick axe but the spike it great for breaking up bits lower in the ground and levering them up

[bristoltype603]

KTMsm said:

FiL was a fencer - he made short work of similar in my garden

He used a 6' steel spike to crack the conc in half (surprisingly easy) then re concreted using the suitable sized chunks in the mix

He was 70 at the time

Was this the item in question?

https://www.fourseasonsfencing.co.uk/shop/product/...

or possibly this?

https://tate-fencing.co.uk/product/roughneck-posth...

[_Hoppers]

If it’s not too late get some of these for the posts https://www.postsaver.com/?gclid=Cj0KCQjw6-SDBhCMA...

[Kinkell]

Posts fail just above ground and leave a root of solid wood in perfect concrete. Removing that root requires my ingenious solution of driving 2 off 10 inch coach bolts into the good wood with a link of steel between the bolt heads. Next step is to lever the link upwards using a pinch bar or 2 jacks and a straight bar between them. Root removed, chap the new post in and podger with a postcrete slurry till firm. Job done. Forty years assisting folks with all sorts of st in their gardens, my legacy.

[UnclePat]

Not helpful for the scenario in your photo above (because you’ve already removed the post), but if you have any other wooden posts that are not yet in danger of snapping completely and just a bit rickety, then consider using these Post Buddy bars: https://postbuddysystem.co.uk/

They hammer down between the post and the surrounding concrete, then you screw the exposed part to the lower part of the post. Needs two per post to be effective. Effectively they ‘knit’ the solid below & above ground parts of a post, strengthening the weak junction at ground level.

Not beautiful, or as good as a full replacement, and I was sceptical, but they vastly firmed-up (even if not absolutely, immovably rock solid).

Saved me digging out concrete in one particular area (exactly as you have pictured) and making a mess. Had already replaced neighbouring posts in soil with postcrete, properly.

Might offer quick & easy reinforcement in areas, as opposed to replacing every single post.

[Evoluzione]

The image shows nothing.
A measurement would be very helpful though. The number of posts you need to do and how big the post is compared to the old one.

[skilly1]

UnclePat said:

Not helpful for the scenario in your photo above (because you’ve already removed the post), but if you have any other wooden posts that are not yet in danger of snapping completely and just a bit rickety, then consider using these Post Buddy bars: https://postbuddysystem.co.uk/

They hammer down between the post and the surrounding concrete, then you screw the exposed part to the lower part of the post. Needs two per post to be effective. Effectively they ‘knit’ the solid below & above ground parts of a post, strengthening the weak junction at ground level.

Not beautiful, or as good as a full replacement, and I was sceptical, but they vastly firmed-up (even if not absolutely, immovably rock solid).

Saved me digging out concrete in one particular area (exactly as you have pictured) and making a mess. Had already replaced neighbouring posts in soil with postcrete, properly.

Might offer quick & easy reinforcement in areas, as opposed to replacing every single post.

I recently found and used these on 2 posts and they work great.

[Clifford Chambers]

Something bodgetastic that should work.

Concrete a metpost into the hole.

[PAUL500]

I had to replace a few posts recently that had been set in solid concrete and had rotted out at ground level, the post above the rot was still solid, as was the timber about 2 inches down in the hole and was going no where despite all attempts to drill it out.

The solution I came up with was 1" angle, spiked at one end then driven into each corner of the hole for a depth of about 12 inches, with another 12 inches left exposed. I then cut off the rotted base of the post back to sound timber (only about an inch lost) flipped it upside down then shaved a few mm off each corner of the existing post with a plane to allow for the thickness of the angle, slid it down into the 4 corners of the angle in the ground, drilled a few holes each side of each angle and inserted green coated screws. Stronger than the original posts! capped the top off and stained, job done.

In the OPs case he could do the same but attach the angle to the post first, fill the hole with liquid postcrete and set the angle down into that then just shorten the post at the top to match the top of the panels.

[steveo3002]

torch light down the hole to see whats stopping it ? if you still cant get it in id whack the concrete and crack it a bit ...wiggle the post in and use a bit of postcrete in the new gaps you made

[PAUL500]

Its likely the original post was simply sawn a few mm narrower at the mill than the new post, or the new ones are wet and have expanded slightly so wont quite slide into that hole. A good tap from above may well drive it in anyway or you could shave the 4 sides of the post down a bit, also maybe oil/grease up the first foot of the post then drive it in. The new post might also be slightly twisted/warped, try the other end or another post.