Drying/curing time for screed

[silverhornet]

Ok, I'm about to embark on levelling a concrete floor with BAL Multibase after filling in some 50mm holes with 4:1 screed (1 hole was 1.5m X .5m and the other was 2.5m X .9m).

I am desperate to get the finally part of the levelling done but I have two queries/concerns:

1) some of the new screed appears powdery to the touch (this could be because I tried to smooth it out with a float practically straight away). Do I need to apply some stabilising solution prior to Multibase or will the PVA I'll be using for a primer be sufficient? It isn't that bad, I mean the dust comes off whilst brushing it and then only a small amount.

2) how long do I need to leave the screed before I can use the self levelling compound? Does the screed really take 2-3weeks and do I need to wait that long before I can apply the SLC? How long do I need to leave it before I can walk on it safely?


Any advice greatly appreciated as always

 

[Jasonb]

I'd give the screed 14days to dry out then brush off and vacuunm up any dust, coat the floor with BAL Bond SBR (not PVA) then apply the Multibase.

You can walk on the multibase after approx 3hrs buy I would leave it 24hrs before tiling assuming you are going to tile.

If you were in a hurry you should have used BAL Quickset cement for your screed then you could have selfleveled the next day, you'll know next time

Jason

 

[silverhornet]

Thanks Jason,

As long as I'll learn I'll make mistakes....

Can BAL Bond SBR be used over the remains of bitumen?

Ian

 

[Jasonb]

In that case I would use the SBR on the repaired areas to stop any dusting and just go straight onto the old adhesive residue with the Multibase.

More details of the products here

Jason