Fencing

[I'lltryanything]

I have taken on a relatively straight forward DIY job. I have a narrow garden requiring replacement fencing. I have 3 panels and 5 fence posts (concrete). I decided to use Rugby Cement Post Mix. I had to make one hole pretty big as the post was going next to an older post set in its own concrete. to cut a long story short the hole was very big and so I filled some of the 2 foot hole with ballast round the bottom of the post.

Can someone confirm, do I have to put hardcore or such like under the post (my ground is very much clay!) Also do I have to put any other hardcore in the hole or can I simply poor in the postmix. The other question is they say a bag a post, well even if I'd dug a normal hole when it has to be 2 ft deep one bag won't do it. Am I doing something wrong?

How long does it take to go solid as the post still has some movement and the mix does not seem that dry after 5-6 hours.

Whats the best way to dig 12" by 12" holes in clay as a normal post augur is not enough and a drill thing would make it to narrow.

Any help suggestions or advice gratefully received.

 

[masona]

Can someone confirm, do I have to put hardcore or such like under the post (my ground is very much clay!) Also do I have to put any other hardcore in the hole or can I simply poor in the postmix.

Hardcore is idealy to mix with ballast and not postmix

The other question is they say a bag a post, well even if I'd dug a normal hole when it has to be 2 ft deep one bag won't do it. Am I doing something wrong?

No you not, I have even use 3 bags per post !

How long does it take to go solid as the post still has some movement and the mix does not seem that dry after 5-6 hours.

Maybe the post movement is causing by the wind if the post is not supported correctly and when concrete dried you have a movement, if that's the case then make some cement grout (cement & water) and pour it into the gap. Make sure the post is well supported

Whats the best way to dig 12" by 12" holes in clay as a normal post augur is not enough and a drill thing would make it to narrow.

A very long narrow spade or this.

 

[oilman]

Ideally, post holes should be bigger at the bottom than at the top, not easy, but that's the way it is.

 

[I'lltryanything]

Thanks for this, just about finished. Rugby Cement Postmix is not great stuff I have found and I have done the rest of my posts with Blue Circle POstcrete. All the posts are pretty much solid now and I have stopped the concrete a few inches short of the path they are up[ against, have then laid soil over that and will add gravel once the gravel board is in. I think it took 2 1/2 bags per post. Just hope I got all the bubble out otherwise could have trouble later but it seemed ok. At the bottom of the holes I added some bricks to stop initial movement, added a few inches of hardcore around that lot and then added the postcrete on top of that...hey presto seems good at the moment. Will let you know if problem start.

Main thing is they are concrete posts so at least they won't rot, they'll just fall over