8ft or 9ft fence posts.

Hi all,

Hoping for some advise with fence posts.
I am going to be installing a large number of concrete fence posts soon (over 30) in my garden as I am tired of the current wobbly spiked-down wooden posts that are leaning at various angles...

I have 6ft panels and and was looking at 8ft concrete posts, this seemed reasonable to me, however I was also considering that in the future I might want to add a gravel board to increase the panel lifespan.
Once I do this, there is now 6' 6" above ground and only 1'6" below, would this be okay?

I can get 9ft posts but these are quite a bit more expensive once I consider the total number required. Would I get away with 8ft posts considering that they will be concreted in.

Would adding an X" foundation below the posts when I pour would do just as well as having a longer post, I can suck it up and get the longer ones if people think it is needed - but I'm not sure - hence why I am here.

The other question I have is that for some of the posts both myself and the neighbour have a concrete path running close to the fence, leaving only about a 4" wide gap, this is enough for the posts but does not leave much room to dig (and possibly undercut for the concrete) any advice on digging in a narrow gap?

Finally any general advice for putting in concrete posts, I've heard make the hole 3 times the width or the post and concrete in - would others agree?

use a posthole digger

Why not use godfathers? That way you can have the strength and save costs.

Current plan is to get a posthole digger and a manual auger.

Can't use godfathers due to the parallel paths each side of the fence, only wide enough for one fence post and if I used godfathers it would move the boundary (also the posts are pretty shot and starting to rot in places).

Main issue is on the length to get, I would have 6' 6" overground and either 1'6" or 2'6" below depending on if i go for 8's or 9's.

Ah, okay I see.

Personally, I would think that 2' for an 8' post would be required but I've only ever used wooden posts and godfathers (never used full-size concrete posts)

Therefore, I would wait for one of the fencing experts on here (there are a number of them) to give you a definitive answer.

FWIW, I bought a cheap manual auger last time I did my posts then used the appropriate spade for the holes.

Sorry I cannot assist further.

B

I used 8ft posts, 1ft concrete gravel boards (set slightly below the surface to obstruct weeds and animals); 5ft panels (featheredge is better than lap)

IIRC you are supposed to have planning permission for a fence above 6ft.

If you want, you can use dark chocolate masonry paint for the concrete to make it blend in with the woodstain. Apply before building.

Well I have done some more measuring up of the existing fence.
A small section is concrete already which is why I wanted to go that way, this section is 6' 4" (it has concrete gravel boards that are buried about 2"), so I think my plan is to do the same / similar.

But now I have a 1' 8" under or 2' 8" under dilemma - one seems not enough and the other complete overkill.
I'm almost tempted to dig round one of the current concrete posts to see what size it is as it has been there 20+ years but knowing my luck if it did that it would fall over after...

@JohnD you only need planning for a fence over 2 metres (which is a touch over 6' 6" so I am safe there).

1' 8" will be plenty unless its very exposed. You will find it almost impossible to dig a post hole a proper width without having the full size opening at the top. Trying to undermine a concrete path will be hellish so you may need to cut sections of it out.

Post hole diggers are only usefull for scooping out loose soil at the bottom. Better saving your money and buying a good draining spade instead if its a one off job.

I've lost count of the amount of 6' panels with 6'' GB's that I've installed with 8' posts and I have never had a single failure.