ᐅ Underfloor heating in the bathroom not possible – can that be true?

What always works is an electric underfloor heating system in the bathrooms. It’s not particularly efficient but is hardly ever used anyway. Placing the mat under the tiles shouldn’t disrupt the construction. I’d like to see how heating with radiators using an air source heat pump at -5°C (23°F) can be efficient. Why not just use a gas boiler?

We want an air source heat pump; a colleague has one and it works well! We don’t want gas, it would only have been an option if we had a natural gas connection.

It’s definitely possible, no question.
However, an air source heat pump is designed for low flow temperatures and therefore best suited for underfloor heating systems.
The general contractor will likely offer suitable radiators, hopefully. Still, using radiators will generally be less efficient, especially at low outdoor temperatures.
I was assuming natural gas supplied through a pipeline; I wouldn’t want a propane tank either.
Having underfloor heating everywhere would be better overall, although I understand your wife’s preference—I also don’t like warm floors.
Is a horizontal ground heat exchanger or deep geothermal drilling not an option? Those are less affected by cold temperatures.

If I remember correctly, a user mentioned a few weeks ago that his wife had the same issues. He installed a ceiling heating system.

It’s just not something for the standard general contractor.

Why not pellet heating and radiators?

We have a prefabricated house with a screed floor in the bathroom and a level floor finish; why shouldn’t that be possible?