My bathtub, or rather the Styrofoam holder, lies on the concrete. This makes getting in very comfortable. And because of the Styrofoam holder, the tub is not cold either.
Quite pragmatically considered, nothing. But you won’t find anyone who will build it for you with a warranty like that.
I’ve also heard that you can’t install underfloor heating under a flat shower tray. Because it can then expand/work and the heating engineer wouldn’t do that.
The heating engineer would only lay the underfloor heating under the shower if you make a tiled, level-access shower.... that’s what you mean with warranty, right?
Delivery surface, it is not about getting a warm tub but warming the screed. If nothing is installed under the tub, the warming is done by the loops next to it.
I also heard that you can't install underfloor heating under a shallow shower tray. Because it can expand/work, and the heating engineer wouldn't do it.
The heating engineer would only lay the underfloor heating beneath the shower if you make a walk-in tiled shower.... is that what you mean by warranty?
If the heating pipes are not embedded in the screed, they naturally have no protection and could be damaged. Therefore, my statement is that no one will do that with a warranty, even if it might certainly be possible and sensible.