LVT over a cemfloor liquid screed with UFH

[iMCaan]

 

 

We are installing epoxy flooring on the Cemfloor screeded ground floor with wet UFH.

However, due to cost we are considering fitting ~200m2 of LVT (loose-lay (preferred) or glue-down) on the first floor, which is also Cemfloor screeded with wet UFH. 

My understanding is Cemfloor, which is cement based, doesn't need sanding. It just needs a good clean and a primer. Furthermore, it should already be level so it doesn't need a self levelling compound or does it?

 

Thanks

 

 

Edited October 2 by iMCaan

[Conor]

We laid ours on 2mm foam underlay. Great job. No messing around. All I had to do was give the cemfloor a Scape to get rid of blobs of plaster etc.

[iMCaan]

Thanks

 

I take it you used LVT panels that click together?

[Conor]

Yep, click fit stuff.

[Kelvin]

You need to make sure it’s completely flat and smooth. The builder badly installed LVT at our previous place and you could see all the floor imperfections under the LVT. They had to lift it and fix the floor and relay.
 

It’s also better to fit LVT that isn’t shiny and has some kind of texture especially if you have a large floor length window opposite it. The first type that went down was a shiny smooth wood effect type and showed every tiny surface scratch. The second type was more matt textured wood effect. The difference was night and day. Both were Amtico. 
 

I also wouldn’t assume it’s level without checking. We had one room where it wasn’t in that it was slightly higher than the hallway. This was due to the hardboard crack inducers across the doorway. No issue for us as we were tiling over a decoupling mat. 

[iMCaan]

Thanks for sharing your experience. Good to know about LVT shiny/matt textured finishes.

 

I can go round and scrape off all the blobs of plaster using a metal scraper and vacuum the floor after. Would it need to be more smoother than that. If so, then the floor would need need lightly sanding?

 

 

[Kelvin]

How thin is the LVT you’re using? The click LVT stuff is generally thicker than say the Amtico stick down stuff. Some folk also lay it on a foam underlay. The thicker it is the more forgiving it is I expect but you still want it scrupulously clean. 

[iMCaan]

I was considering going for loose-lay LVT, which is about 5mm thick. The glue-down LVT is about 3mm.

[Kelvin]

Still quite thin. Imagine a small stone under that. 

[MikeGrahamT21]

Consider SPC LVT rather than the normal stuff, it’s a lot stronger and tends to have integrated underlay, this is what I used in bathroom recently and it was good stuff to work with

[Chanmenie]

I considered using click LVT or SPC but for a bathroom the need for expansion gaps made me decide to go down the glue down route.

My subfloor was 22mm caberdeck so I screwed down 9mm plywood.

For a concrete floor you really need laytex / sell levelling compound as it needs to be really smooth and flat.

For our downstairs we are having glue down LVT installed, the installers are going to grind the concrete and screed with self levelling compound.