My friend Abe is correct. Even though a room with a window unit won't have the same per square foot value as the rest of the house (providing the entire house isn't heated with window units) it does indeed have value. The rule of thumb is the sunroom would have 50% to 75% of the value of the rest of the house.
Regards, David Wilson
Keller Williams - Greenville, SC
No, a room with just a window unit is not considered heated living space, unless of course the entire home is heated and cooled by these units, which is highly unlikely. Heated square footages are based upon rooms heated with a permanent heat source.
Hope this helps!
Keller Williams Greenville
If it is permanent, the answer is usually going to be Yes; however, as Gerard wrote, check local customs and get a realtors advice. A Realtor will be able to evaluate the room and determine if it is going to be additional square footage. I hope you are able to find the home you are looking for!
A removable unit - may not qualify.
How long have you owned the home? Was the sunroom considered part of the square footage when you purchased the home? Does your tax assessment include the sq footage of the room? Was this room a patio that was converted into a sunroom? These are a lot of questions - but this isn't a yes or no answer without answering these questions and more. I agree with earlier responses - to check with your local housing/building authority for exact value.
I hope this helps.