Self Levelling Compound issue (pictures) - TilersForums.com

[JordanLincs]

So it's morning time and everything seems okay i think. However, the top layer is soft-ish (sratches with a screw driver). To be fair its about 5c° so I think it's a combination is a weak-ish mix and very cold temps as to why the top layer is a bit soft? It feels like one more day and it will be rock hard

Secondly is not as flat as I'd like. I was planning on fixing a batten to the door and putting down another layer. I need to wait and see if it gets more solid. Do I need to prime again?

 

[hmtiling]

So it's morning time and everything seems okay i think. However, the top layer is soft-ish (sratches with a screw driver). To be fair its about 5c° so I think it's a combination is a weak-ish mix and very cold temps as to why the top layer is a bit soft? It feels like one more day and it will be rock hard

Secondly is not as flat as I'd like. I was planning on fixing a batten to the door and putting down another layer. I need to wait and see if it gets more solid. Do I need to prime again?

Definitely prime and you can use expanding foam as a dam.

 

[JordanLincs]

Definitely prime and you can use expanding foam as a dam.

Good idea, thanks!

 

[Qwerty]

Thats about normal for next day

 

[JordanLincs]

Thats about normal for next day

Is it ok to lay more self-levelling compound even though there is a thin crumbly layer on the top?

 

[Waluigi]

Is it crumbly? It looks fine to me.

Get a straight edge on it to check how flat it is and crack on.

 

[Time's Ran Out]

Is it ok to lay more self-levelling compound even though there is a thin crumbly layer on the top?

For me I’d only do the self leveller once. If it’s crumbly then it’ll have to be rubbed down and primed or your adhesive won’t stick.

 

[Old Mod]

As above, if there’s what appears to be a crumbly top skim, then it has to be removed, scraped back and primed.
Otherwise at some point if you try stick to it, it will release and floor will lift.
Are you sure it’s still not drying?
If it’s slightly overwatered and cold, it may not have fully dried.
Whichever way, only fix or add extra latex to a solid surface.
Pointless otherwise.

 

[JordanLincs]

As above, if there’s what appears to be a crumbly top skim, then it has to be removed, scraped back and primed.
Otherwise at some point if you try stick to it, it will release and floor will lift.
Are you sure it’s still not drying?
If it’s slightly overwatered and cold, it may not have fully dried.
Whichever way, only fix or add extra latex to a solid surface.
Pointless otherwise.

Yeah because it's very cold and was a watery mix it might still be drying. I'm gonna leave it another day and see what happens. If it's still got a crumbly top skim then I will remove and crack on.

Most of the area is flat, however it's not flat in some areas near the door, more than 3mm. When coming to the end of pouring the SLC I notice some sludge/thicker SLC which has not spread in some areas and created to higher points

 

[Old Mod]

If you have a rubbing block, or @Dan’s favourite a brick, you can rub down any high spots if it’s slightly soft, just go steady.
Only if you can reach from outside.
You’ll know if it can take it the moment you touch it.