Fence post concrete : mix ratio & amount

[InfAddict]

Hi, after the windy weather I'm in the process of replacing 6 fence posts and several panels. So far I have done the hard part in digging out and removing existing damaged/rotten fence posts and the concrete at their bases. I've dug down 2' and the holes are about 1.5' square.

What mix do you recommend for a standard 6 foot high panelled overlap fence? The local BM is telling me equal measures of cement, sharp, gravel, but I thought something like a 1 cement, 3 sharp, 3 gravel would have been adequate.

Also, to fill these six holes how much do you reckon I need in total?

Thanks in advance for any advice.

[lee]

hi ya Infaddict

for an 8ft post being sunk into the ground 2ft, I would normally use a 4:1 mix of 14mm to dust : cement
I purchase the 14mm to dust in 40k bags, cement comes in 20k bags
1 bag of 14mm to dust mixed with 1/2 a bag of cement will cover 1 post

The width you are digging i estimate you will probably need 2 bags of 14mm to dust and 1 bag of cement.

so you would be looking at 12 bags of 14mm to dust and 6 bags of cement
Please note, the bags i buy are 40 kilo....most bm's now have to sell the bags at 25k i think.... health and saftey brought the weight down!

cost wise 3 quid a bag of 14mm to dust and cement has risen recently due to new additives mixed in...should be around the 4 quid mark.

hope this helps

[Tool]

Well i 600mm or 2 ft is a nice depth for your posts, well the mix you want is 4 parts gravel 2 parts sharp sand and 1 part cement so basically it is a 1 in 6 mix.

You can go 3 parts gravel 3 parts sand if you are wanting to rub it up nice but the 4, 2 ,1 mix is what i use for my fence posts and never had one blow over yet.

i priced up a few fences in the past week or 2 and because they were put up by john wayne and the rest of his posse what a mess to sort out i come across guys not putting them in deep enough and chopping the tops dow so they look like they are in 2 ft.

i was always told to bury 1/3 of the post in the ground the old boys had the right idea

[InfAddict]

Thx for all the replies guys.

I've bought the cement, sharp and gravel now. Would you believe that Wickes was cheaper than all the local BM's.

Also got 9' posts as they will be 2' under and will be against the neighbours garden which is raised about 1' also.

Dunno if there's a better way to do it, but I'm gonna run a string line from the first to last existing posts and then use that as a guide for my new posts. I will attach temp supports to each new post to keep them upright whilst the concrete goes off. I'm guessing the hardest part is getting exactly 6' between the posts so that the panels fit nice and snug.

Thx again for the advice :;): .

[James C]

The easiest way is to fit the panels as you go. First drill the battens on both ends of the panel to prevent the fixings from splitting them, then fix it to the first post, level top of panel and locate your next post on the other end. Plumb up each post and prop. Carry on like this down your garden. James

[dig dug dan]

Best of all guys, use a 6" timber gravel board under the panels. Attach the gravel board to some wooden cleats (1 1/2" x 2") then attach on the the post. this will not only give you the spacing, but will stop the panel rotting at the bottom.It also means the panels can slot in later when the concrete has set, so if it is windy, it wont move the posts. This way you dont have to prop up the fence to keep it upright.
Using a gravel board is the proper way to fence. and by the way, dont use 3" posts above 4' fence height. The fence will not last more than 4 years.Dont forget post caps either, and use galvanised nails. stops rust marks!

[InfAddict]

Some great ideas there lads . Sadly dan, I've just put up 6 posts which are 3x3 and supporting 6' panels... hopefully they won't fall down anytime soon.

I ended up using a mix of 1 cement to 3 sharp + 3 gravel and it has worked fine. However, it took a lot more than I thought to fill the 6 holes. Back breaking work mixing it all up on a board (for someone not used to hard graft) !!!

[Tool]

Well done m8 i remember when i just left school and i was working at a large mansion house with the head gardener and he had me mixing of the board and i know what it is like.

Now and then i mix small batches by hand if i cannot be bothered getting me mixer mucky for a small amount.

i will tell you what is harder, try mixing skim coat plaster in a bucket with a plunger, now that is hard going.