TRV's and room stats

[PlumbersMate]

I thought didn't even need to be public, every new build I've been on has them on bath at least

 

[mfgs]

All new builds have them on the bath, infact any new bath fitted should have one. But basins etc don't need them in domestic, I don't usually get involved in anything outside domestic houses so I am a little unsure on whats required.