I've just laid self-levelling compound (Wickes Master Latex) ranging in thickness from 3mm to about 8mm. This was laid to encapsulate a heated floor element and to level the floor surface.

The SLC is on top of a 12.5mm layer of Aquapanel, which is laid with a 3mm bed of waterproof tile adhesive and screws onto a 21mm water resistant chipboard floor.

I'm going to lay 450x300mm tiles onto the SLC using Bal Rapidset Flexible, and have a few questions:

1. How long should I leave the SLC before I can tile? It's been down 24 hours now.

2. I have a 20mm solid bed trowel - will this be suitable for the adhesive and tiles I have?

3. Should I prime the SLC? The tile factsheet seems to suggest no need to prime sand based screed, but it doesn't specifically list SLC as a substrate. I have some Bal APD to hand.

Thanks!

I would prime the slc

It should say on the bag how long before coverings can be laid, but 24 hrs should be fine ..

As for priming.. if no dust is present then it doesn't really need it as long as you apply addy correctly making sure of coverage.

i usually don't prime the SLC either,it should be well dry by now too.

It is a little dusty, maybe like bare plaster. Do you maybe think a quick vacuum will be ok to prep it for tiling?

That is the reason I prime the slc, it can be very dry and absorbant IMO

Originally Posted by whitebeam

That is the reason I prime the slc, it can be very dry and absorbant IMO

Would you dilute the Bal APD or use it neat?

Dilute 3-1, just to kill some of the suction IMO

I'm not sure whether to use it neat or dilute 1 to 1.

I guess diluting 2 (APD) to 1 (water) would be a good compromise.

Can't do any harm priming I assume - just to be safe...

Allways good to read the instruction on the bottle

Bottle doesn't list SLC unfortunately. Only:

USE UNDILUTED ON:

-plaster walls/plasterboard when using a BAL cementitious powder adhesive
-tongue & groove floorboards
-anhydrite screed floors

USE DILUTED 1:1 with clean water on:

-dusty/porous plaster walls when using a BAL ready-mixed adhesive
-cement: sand screed/concrete floors