I mean, yes, there are standards, but the standards are sometimes shit. As an example - my friend just bought a very expensive brand new house, fancy insulation, but.....all radiators are like 2 feet wide? Even for the living room where intuitively, that cannot be the correct size of a radiator for that. But apparently(having complained) nope, these are regulation size etc. Now he spends 2x as much on heating for a house the same size as his old one built 20 years ago, because predictably, the rooms never get hot enough in winter with those crappy undersized radiators.

Again, that's just anecdote, feel free to ignore it.