The house we're buying has a conservatory (around 15 years old) off the kitchen, with a normal internal glass door between it and the kitchen. It has underfloor heating.
From what I understand, it should have had building control sign-off given that the door isn't an external one. But the sellers haven't got any details on that (previous owners did it).
Does this matter, given the length of time it's been there? Or is there no time limit? Funds permitting, and if we're there long enough, we'd like to convert it into a proper room, but if we don't, are we going to have problems later on when we sell? What's the solution?