Can I have electric underfloor heating in a bathroom without burying it in screed?

[K_L]

I'm doing a bathroom and would like to put one of those thin electric heating mats under the floor. The floor is going to be vinyl with integrated underlay (William Stone Silver SPC from Wickes) on a concrete slab. I don't want to increase the floor level compared to the other rooms much, so I was hoping to get away without burying the mats in screed of any sort. Ideally just a DPC, thin insulation (5 mm Diall polystyrene?), the heating mat, and the floor (6mm including the underlay). Is that going to work? Can I put the heating straight on top of the PS underlay? Can I put the vinyl floor straight on top of the heating?

Wherever I look on the internet, I find bathroom heating always in a layer of self-levelling compound or under tile adhesive. I know the vinyl flooring isn't exactly mainstream, but I can't believe nobody has done this before... Thanks in advance!

 

[stem]

You can buy ufh for use with vinyl flooring

 

[K_L]

Well, the problem with that is that I'd need to have 6 mm board plus some adhesive below, plus tour another 10 mm of levelling on top, so I'm at some 18 mm higher than the other room, which is a noticeable step...

In the instructions to the one you posted (Option 3) they put it directly on top of the Pro-Foam board, which is good, so how about if I put the vinyl floor directly on top of it without the boards? Would that warp or otherwise hurt the flooring?

 

[Murdochcat]

Insulated tiles first are a good idea on the ground floor

 

[foxhole]

Well, the problem with that is that I'd need to have 6 mm board plus some adhesive below, plus tour another 10 mm of levelling on top, so I'm at some 18 mm higher than the other room, which is a noticeable step...

In the instructions to the one you posted (Option 3) they put it directly on top of the Pro-Foam board, which is good, so how about if I put the vinyl floor directly on top of it without the boards? Would that warp or otherwise hurt the flooring?

18mm threshold isn’t a problem.

 

[sparkymarka]

Or

 

[K_L]

In the end I went with this: https://www.theunderfloorheatingcompany.co.uk/product/varme-carbon-film-electric-underfloor-heating/

Negligible thickness, just 6 mm underfloor insulation below and 6 mm vinyl tiles above, should be about the same height as the next room, let's hope it's all going to work out