what's the best way to seal off our sunroom so we don't pay to cool it? It's really humid AND hot in MS this time of year (avg 90+ F). We have a very "open" house, with a large dining room connected to the sunroom by one normal "door hole" AND one "double door hole", but the openings are...well, openings. There's nothing at all there. The sunroom doesn't have a/c, and only has single pane windows...about 10-15 of them, floor to ceiling. It's a round room with practically no wall except between the windows.
Solutions? -door(s)? -curtain(s)? -"magnet" curtain(s)? -blanket(s)?
We rent the house, so major reconstruction isn't a reality. Nor a desire...
edit: infrequent access is still necessary to the room.