Sheet Vinyl In Basement - Underlayment?

[JerryInMaine]

Would like to put "loose-lay" sheet vinyl in our basement. Slab has a vapor barrier and insulating foam underneath and has always been dry. The issue is that there used to be a hot tub in one area, and the surface of the slab floor has sections that were painted with a non-slip coating which is a bit rough - like sandpaper. To avoid having to sand this off and to provide a smooth surface is there anything I can put under the floor as an underlayment to cover the rough areas?

 

[Floorist]

Not really.

 

[Tile Tom]

Skim coat the rough areas with ardex feather finish. Knock down the high spots with a chisel or scraper first

 

[Incognito]

I'd have to see to confirm but I don't think it needs to be sanded or skim coated. Probably fine to lay over as is. But if i were worried a skim coat is a real easy fix............at least for me.