Self Levelling Compound on top of new concrete

[nohope17]

Hi. First time poster here.

I've repaired a section of floor which use to be an old shower. I put down a base of concrete and plan to finish off with a layer of latex self leveling compound to bring it up to the level of the existing floor.

How long do I need to leave the concrete to cure before adding the leveling compound to the top of it?

Is there any other prep I need to carry out. I read about applying a layer of PVA?

I can see anything on the packaging, or on the web.

Thanks!

 

[noseall]

In warm dry well ventilated conditions 100mm of concrete should dry out in about three weeks. Probably double that in the winter!

No need for pva.

 

[xdave]

Place a piece of clingfilm on the floor, weigh it down around the edges and leave it overnight. It will show as a damp patch on the floor if there is still water evaporating out of it.

Even though the area sounds small enough to level in one pour I would still seal it to stop the concrete from sucking the water out of the compound too quickly. Otherwise, like any cement-based product, it could leave a very weak and crumbly finish. It seems to be more of an issue with formulas containing latex which end up being as soft as a sponge if the water is lost before the cement has a chance to form its chains. Any synthetic floor primer would do - acrylic ones are cheaper than quality PVA and do a much better job.

It is important to spike latex compounds to remove trapped air. If you don't have a roller, and can't justify the £40 cost to buy one for such a small area, use a hairbrush with solid combs approximately every 5mm and tap from above. It will wash off.

 

[nohope17]

Thanks chaps.

I put bin bags over the top of it and kept it moist for 3 days, I've now allowed it to dry out.

This is the before and after

Untitled

• nohope17
• 31 Jul 2014
• 1

Untitled

• nohope17
• 31 Jul 2014
• 1

I pulled out the old blue shower tray, and the shower tray that was on top of that!!

I need to to be fairly strong as the washing machine will go in there