Harold:
210.52 includes 'sunrooms' within the text. Quite a few in my town have heat and ac, and zoning refers to then as 'sunrooms'. So, they are treated the same as any other room in a dwelling.
I had a 'gazeebo' last week, which actually looked like a structure at a scout camp, that conformed to 210.52 from the factory. (pre-fab unit)
