Height of external door?

[elm]

We have a really, really nasty swirly frosted glass and alluminium front door which we are looking forward to replacing. The glazing in the door is the only source of daylight in the hallway. The doorway itself is quite tall - I think originally there would have been a solid door with glazed lights above and that's what we'd like to replace the existing door with. I'm just wondering if anyone can tell me whether there any regulations that dictate a minimum height that an external door has to be?

Many thanks