Hi all,

 

We quite like the matt/polished concrete look and there are a few concrete-based SLCs available (Screwfix's own has come recommended by several people).

 

Our current plan is to put the SLC down prior to LVT flooring but I was wondering if a concrete-based SLC can be used as a finished floor? If so, is there anything particularly to look out for? 

I'm no expert in tis but the Screwfix (No Nonsense) stuff I've used was (a) a bit too weak and crumbly once it set to use as an actual floor surface and (b) actually quite difficult to get accurately flat.

Oddly enough (luck, not good judgement!) I never had difficulty getting SLC well, level, but it did not last well as a final finish. I used it on my Damp) cellar steps, with sanded bitumen below. It lasted a fair few years but cracked a bit as it went on.

Thanks both. Interesting that you found it “crumbly” and difficult to get flat @Alan Ambrose — was this their standard SLC or the slightly more expensive concrete-based one? I've only seen good reviews of both.

 

@Redbeard Might it have been the bitumen base that contributed to the lack of longevity? Genuinely don't know. We'll be pouring the SLC onto C35 concrete.

I was using this stuff: https://www.screwfix.com/p/no-nonsense-2-part-floor-levelling-compound-12-5kg/27894

 

Maybe it was all my fault ... I might choose the Mapei stuff now just because I've had some good results with their products in the past.

Ah, thanks Alan. I'm looking at this: https://www.screwfix.com/p/no-nonsense-cement-based-levelling-screed-20kg/116hu

 

Good to have your feedback on that one though, thanks.

It can look quite patchy in colour and texture. I'd be surprised if it looks good enough for a finish.

Also it's quite brittle so might crack or lose adhedion if something is dropped on it.

Latex based stuff is more flexible. There used to be 2 part stuff that was great but I havent found any recently.

You can make yourself a little test board from some ply etc with a little lip round it. Maybe try it out with the depth you're planning and see how you feel once it's set?

Thanks both - really helpful suggestions. I will make up a test board as suggested and see what it turns out like.

 

Noted also on latex; this was recommended by a few others to me too. I suspect we'll end up going a latex SLC route with LVT or Karndean/Amtico on top.

On 21/11/2023 at 16:55, Ben Weston said:

Redbeard Might it have been the bitumen base that contributed to the lack of longevity? Genuinely don't know. We'll be pouring the SLC onto C35 concrete.

 

Absolutely. It was plainly not a recommended application, but given that, as a bodge, it was remarkably successful.