Self Levelling Compound Mixing

[nibblitz]

Well, the father inlaws concreting job for my conservatory floor is more up and down than the Brecon Beacons, so I need to level it off... I know the normal way is to mix in a big bucket with a paddle on a drill, but my question is this.. As Im probably gonna have to do at least a couple of mixes, and that I have a cement mixer sitting here doing nothing, could I mix the whole lot of levelling compound in the cement mixer instead of mixing individual bags in a bucket? I just see it as being a bit easier to mix and pour the whole lot in one go.. Or am I daft for thinking I could use the cement mixer?

[daithi]

no mate ya can just make sure the cement mixer is clean beforehand dont want any stones etc in the mix

[gizmo.1484]

Well, the father inlaws concreting job for my conservatory floor is more up and down than the Brecon Beacons, so I need to level it off... I know the normal way is to mix in a big bucket with a paddle on a drill, but my question is this.. As Im probably gonna have to do at least a couple of mixes, and that I have a cement mixer sitting here doing nothing, could I mix the whole lot of levelling compound in the cement mixer instead of mixing individual bags in a bucket? I just see it as being a bit easier to mix and pour the whole lot in one go.. Or am I daft for thinking I could use the cement mixer?

Mixing in a cement mixer will be fine... just make sure you don't over mix it, or you will struggle to lay it.

[nibblitz]

Many thanks guys, Im not so moody about the uneven floor now. Being able to mix it all in the cement mixer is gonna make the job a hell of a lot easier... Yayyyy...
:)

[nibblitz]

Oh dear, It now seems I need quite a few bags of this levelling compound, and it aint cheap, arrrrgggg... Ive bought a few bags of Wickes deep base compound, but am worried I might even need more.. Considering this is just to flatten the floor ready for laminate flooring, could I bulk out the compound mixture with sharp sand to make it go further? Say like, 2x 20kg bags of levelling compound with 1x 25kg bag of sharp sand in the mix?

[gizmo.1484]

If the floor is that uneven you would be better off screeding it, using cement and sharp sand to a ratio of 1:3 or 1:4.5 depending what going on top.

You can't mix compound and sharp sand together as it will just crack when it starts drying.

[nibblitz]

I thought about screeding but then thought it might not be a good idea, the thickest low areas will only be 20mm, with most low spot areas being like from 5mm to 10mm.. I imagine screed would just crack from being too thin..

Oh well, I'll just have to buy more bags of compound if I need it... What an annoyance, this is a prime example of how a bad job makes twice as much work..

[gizmo.1484]

Yes a 5mm screed will crack...So it looks like you will have to stick with the levelling compound, but at about ?10 a 20kg bag it's not going to be cheap.

The person who laid the concrete slab should have used a power float to get a level surface. Or left it a little lower if doing it by hand so they could finish it with a screed...