concrete base

[markyyyyyy]

I'm building a concrete base that will have 75-100mm concrete depth

The area is 9 square metres

Is this too much of an area to mix using a cement mixer rather than getting ready mixed delivered?

How long will concrete last in terms of being able to manipulate it so that i can tamp it down level

Any tips to get a perfectly level base other than shuttering with timber and using a timber edge?

 

[Ian H]

I just did one 2.4 x 2.4, 125-150mm thick with a mixer. 2 bulk bags worth of ballast, 6:1 mix, no problems with it starting to set and I levelled it with timber dragged over a timber frame.

 

[Mobo_14]

I’d price getting concrete delivered and barrowed round if possible.

Sometimes cheaper, quicker and saves you mixing it.

 

[markyyyyyy]

I just did one 2.4 x 2.4, 125-150mm thick with a mixer. 2 bulk bags worth of ballast, 6:1 mix, no problems with it starting to set and I levelled it with timber dragged over a timber frame.

Great cheers. Did you find that the concrete was perfectly level with no rough spots?

Did you have to trowel any parts to get smooth?

How long did you leave timber shuttering in before removing it?

 

[Ian H]

Perfectly level but a few slight indents where the wood caught stone.

I trowelled all I could reach once I finished levelling it.

The timber is still in there, it took over 24 hours to cure, to be honest I was ****ting it because I thought the frost killed it but it’s rock solid today.

 

[Ian H]

That’s before I went over with the trowel.

 

[domdee]

Your looking at 0.9m3 if you go 100mm deep. The cost of ready mix will quite expensive as its a small qty. I have found recently due to doing similar my self that they often charge you for empty space in the mixing wagon.

I'd do it myself if i was you. You'll probably need 2 bulk bags of ballast (2ton - £40 ish each) and a mix of 5:1 with cement (16 bags of 25kg cement - £5 ish each).

£160 and a mornings graft.

 

[Ian H]

A place near me does volumetric at £150+ vat for the first cube then £100+ vat for each extra cube.

 

[Mobo_14]

A place near me does volumetric at £150+ vat for the first cube then £100+ vat for each extra cube.

To me that’s a no brainer then get it delivered with probably 1 or 2 guys bringing it round for you (whilst you hold the rake obviously) with zero mixing required.

 

[markyyyyyy]

Perfectly level but a few slight indents where the wood caught stone.

I trowelled all I could reach once I finished levelling it.

The timber is still in there, it took over 24 hours to cure, to be honest I was ****ting it because I thought the frost killed it but it’s rock solid today.

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Looks a good job you've done there.

Are you keeping the timber in?

When you levelled the concrete by using the timber, did you just run it over or did you use a sawing action with the timber while sliding along?

 

[Ian H]

Yes, going to leave the timber in it will be under fake grass.

I first tamped it in an up/down motion then sawed it across twice, first time was hard because I had too much stuff in. I scraped the excess off with a trowel. Second time was easy and got it really flat.

That was on Sunday and I walked on it for the first time today.

 

[^woody^]

Perfectly level but a few slight indents where the wood caught stone.

I trowelled all I could reach once I finished levelling it.

The timber is still in there, it took over 24 hours to cure, to be honest I was ****ting it because I thought the frost killed it but it’s rock solid today.

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Is that building sand?

 

[Ian H]

Is that building sand?

No, it’s a really red grit and more random sized stone than the normal stuff I get from Travis Perkins. I got it from a place in Manchester called Cheaper Building Materials and I wouldn’t use them again.

 

[John D v2.0]

When they put cheap in the name of the company you have to be a bit suspicious!

 

[Ian H]

When they put cheap in the name of the company you have to be a bit suspicious!

Yes, lesson learnt. How hard can it be to put sand and stone in a bag? Too hard for them.