Screeded floor, sealing with cement/pva mix

hi guys

Just screeded a 16m sq room last weekend and just covered it up to help slow the drying. I had also sprinkled it with water to help slow it down

I also read about sealing it with cement/pva slurry to keep the dust down. Is this something anyone recommends? If so, is this a good time to do it or wait for it to dry more first?

The end result of the will be laminate flooring put on top. With kitchen units around the sides directly on top of the screed. I’m planning to do this in 2/3 weeks time. So that would be roughly 4 weeks of total drying time for an averages 75 - 90mm screed.

iwanttodiy, good evening.

If the screed was a cement / aggregate [Concrete] type then it is said that the best way to allow Concrete type screeds to "Cure" is to submerse in water, OK that simply cannot happen in the real world.

As for sealing, use PVA suggest you do not use cement, the very thin cement film drying out will tend to crack and craze.

As for drying time for the screed? The screed will dry out at about 20. mm / Month?

Suggest you consider testing the new screed by completely sealing down on to the screed surface some cling film, if moisture forms on the underside of the film it is damp / wet?

Ken

The screed has been laid for a week now.

When I first had a clear polythene sheet over it, there was moisture on the underside of the sheet. That was in day 1 and 2. I took the sheet off, sprinkled with water, and put the sheet back. The sheet has been dry since (last 4 days).

I didn’t seal it tight. But I’ve placed lengths of wood around the perimeter where I can to keep the sheet down.

I think I would like to lift the sheet again and seal with a layer of PVA, or I could put down a layer of SBR. Considering PVA and SBR are roughly the same price, seems SBR would be a more appropriate product?

I remember reading that building regulations require 1mm per day, so for 90mm you may need a bit of patience and allow 3 months or preferably a bit longer before it is fully dry . Diluted PVA would stop the dust which will appear when the screed is swept and fully dry. SBR is usually used for other purposes. When installing laminate make sure the floor is very flat or inconsistencies (high spots) could make some boards eventually slightly come apart from each other in the long run. Hope that helps.