Pier Build Advice Please

[joselin]

As its a bank holiday weekend what better to spend it than building my pier, i have everything ready to go except for buying the cement, sand and coarse aggregate.

This is where i require some direction i will be digging a 2' by 2' by 2' hole and filling a 160mm by 1.5m (ish) pipe, how much do i need to complete the job and what mix shall i use ?

C15P 1 cement, 2 sand or very fine aggregate, and 6 coarse aggregate ?

C20P 1 x cement, 2 x fine aggregate (sand) and 4 x coarse aggregate

C35P 1 cement, 1 stone and 2 sand or 1 cement to 3 ready mixed aggregate.

Cheers

J

[johnrt]

I used cement and ready mix balast from Wickes. I used a 1:4 ratio to fill a 2x2x2 hole and similar sized pipe. It took 2 and a bit bags of cement and 10 bags of all in balast.

Hope that helps.

[johnrt]

The hardest part is the digging. Oh my poor delicate hands

[joselin]

I used cement and ready mix balast from Wickes. I used a 1:4 ratio to fill a 2x2x2 hole and similar sized pipe. It took 2 and a bit bags of cement and 10 bags of all in balast.

Hope that helps.

Thanks, do you remember the weight per bag ?

[johnrt]

They were these ones 25kg.

Ballast - Sand & Ballast - Aggregates -Building Materials - Wickes

[Bizibilder]

I used a dozen ballast and three cement for my same size i.e. 2x2x2 hole! Ballast is only a couple of quid a bag so buy more than you need! You cannot (easily) "add a bit more" with concrete - it doesn't bond too well. You are bound to need a bit of concrete around the place if you have a bag or two too much.

By the way a local builders merchant is almost certainly going to be cheaper than Wickes, B&Q etc (NEVER shop at Homebase - the prices are ridiculous!!!) they may also deliver for not much more - ballast is HEAVY!!

I also used a mixing tray - about 4' by4' from the builders merchant - very useful. For hand mixing I did 3 bags of ballast at a time - that was quite enough for someone who doesn't normally do that kind of work. Always try to mix next to where you are going to put the stuff - its HEAVY to move it around!! (unless you are a builder and then you would know that!)

That pipe will take over two whole bags on its own to fill!

Hope this helps.

Oops! I forgot - when you make the pier allow the base block to "set" for a while before filling the pipe! If you don't the concrete in the pipe may drop and find its way out of the bottom!! - not a major problem but if your mix is too wet be careful!

Which reminds me - don't make the mix too wet! If you take a shovel full of mix, at the right consistency, it should just retain its shape on the shovel. It should NOT run off!! The other test is the pile of mix on the ground should NOT collapse into a "cow pat".

[Kai]

When i did mine a couple of years ago i hired a mixer for the weekend i didnt cost that much and saved my back.

[TopHouse]

The normal ratio for 'standard' concrete, ie house bases etc is 123 thats 1 cement, 2 sand, 3 stone. You want concreting sand not builders sand, some call it sharp sand, others call it grit sand and others call it 'river sand. But if you tell builders it's for concrete, they'll know what you mean.

the 1 2 3 can be shovels, buckets, or whatever else you have to hand (I've always used shovels) renting a mixer is best advised as if you're not used to hand mixing it's a chore!

Measure ingredients first, then dry mix THOROUGHLY before adding water, advice re consistency above is good. Now when you have your hole full, get a stick that will go all the way to the bottom and keep pushing it in and out as you work around the hole, this agitates the concrete and removes bubbles.

Then level it up and leave, if it looks like rain, sheet over it, no danger of frost this time of year so no worries there.

[joselin]

Thanks for all the advice.