Jump to content

Stargazers Lounge Uses Cookies

Like most websites, SGL uses cookies in order to deliver a secure, personalised service, to provide social media functions and to analyse our traffic. Continued use of SGL indicates your acceptance of our cookie policy.

blinky

How many bags of cement & ballast etc do I need for Pier?

Recommended Posts

I'm gonna be building a pier at the weekend, I am reckoning about 0.25 m3 of concrete in total. the foundations will be about 0.5m deep by 0.5m length and breadth, roughly, depending on how easy my ground is to work with!  I am also building a square tube out of decking for the pier itself. So... Around 0.25m3 in total  - now a website I found said that a 1:8 mix is for foundations, and I think this is closest to what I am building? I cant work out how many bags of ballast and cement I need, all the online calculators seem to be using a different mix!

Share this post


Link to post
Share on other sites

I'm gonna be building a pier at the weekend, I am reckoning about 0.25 m3 of concrete in total. the foundations will be about 0.5m deep by 0.5m length and breadth, roughly, depending on how easy my ground is to work with!  I am also building a square tube out of decking for the pier itself. So... Around 0.25m3 in total  - now a website I found said that a 1:8 mix is for foundations, and I think this is closest to what I am building? I cant work out how many bags of ballast and cement I need, all the online calculators seem to be using a different mix!

Hi Blinkey, See my build thread New Obsey in Norfolk UK. I used 2 bulk bags from Wickes and 12 bags of cement at 4:1 (ish)

Regards

Mike

Share this post


Link to post
Share on other sites

Your pier slab looks massive!!!  I don't think mine will be that size, maybe around half of that...

Share this post


Link to post
Share on other sites

I used rather less than that for pier and six support pads for the obsy framework.  I did order two bulk bags of ballast and accompanying bags of cement but didn't use anywhere near all of it - more than one big bag of ballast used though.

Some of the rest came in handy for other concreting jobs around the property and still some left.

Edited by Gina

Share this post


Link to post
Share on other sites

I've tended to use 5:1. I can't comment on UK ready mixed ballast but here in France it tends to be short on sand and gives a rough, gravelly finish, so I always add a bit more sand.

Olly

Share this post


Link to post
Share on other sites

I've just done a 6m x 2.5m slab aound 100mm to 150mm deep for my brewery and engine shed.  I reckon a bulk bag of aggregate (mine are quoted as 850kg minimum weight)  is just under half a cubic metre and I used five bags of cement per bulk bag of aggregate.  In the end I used all of four bulk bags of aggregate and twenty bags of cement for what worked out at around two cubic metres of concrete.

If you want a quarter of a cubic metre I'd probably suggest getting a bulk bag anyhow.  Getting on for 500kg in small bags is going to be expensive, and with the bulk bag you'll have a bit of margin for error.

Do not underestimate the hard work involved in shovelling the stuff from place to place though.  I shifted all of the four tonnes or thereabouts of materials for my slab into the trailer at the front of the house and then from the trailer to the mixer at the back.  I ached for days :)

James

Share this post


Link to post
Share on other sites

Im hiring a cement mixer, and already have a wheelbarrow so hopefully it should not be too dificult

Share this post


Link to post
Share on other sites

I was so unwilling to move the stuff for a third time after it was mixed that I actually stood the mixer in the area that was to be the pad and just dumped each load out on the ground after each mix :)

James

Share this post


Link to post
Share on other sites

That suggests you'd use around six bags of cement per bulk bag of ballast, by the looks of it.  More than I've ever done, certainly.  And nothing I've built has fallen down in the last ten years :)

James

Share this post


Link to post
Share on other sites

just finished mine its 2ft x 2ft x 2.7ft deep with rebar and took 12bags of 20mm stone 8 bags of sharp sand and 4 cement. The pier i used for a 8.5" x 8.5" x 900mm high 2 bags of 10mm stone and 1 bag sand half cement with four rebars 

It takes more to fill than it looks, so if your hole is 2ft cube trying to estimate how many bags will fit in the hole would be actually require more, because once everything has been mixed it's more compact. The gaps between the stones would be filled with the sand and the gaps between the sand will be filled with cement.  

I would get more than you think and just take back what you don't use. If you get thoses 25 kg bags that is.

Share this post


Link to post
Share on other sites

I use mastercrete at whatever mix it says on the bag. About 1:4 cement:all-in-ballast I think.

I'm sure you could get away with less cement, but it's less than a fiver a bag and you only do it once.

Share this post


Link to post
Share on other sites

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.

Guest
Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.


  • Recently Browsing   0 members

    No registered users viewing this page.

×
×
  • Create New...

Important Information

By using this site, you agree to our Terms of Use.