Most below grade spaces are not considered in the square footage of the house regardless of whether they are finished or not.

Dear Vikas, C.O. means Certificate of Occupancy and any new additions to the home must have this. It is usually issued by the Town Engineer and title to the home cannot be passed--e.g. the home cannot be sold without a Certificate.
Alice Feldman http://www.alicefeldman.com

What does CO stand for? Can you please let me know

It is my understanding that even if your finished basement is heated and has a C.O., you should not count the square footage if it is actually below ground-level of the house. For example, in a raised ranch, there is an exit from the downstairs to ground level, so it is not considered a basement. However, if you need to go up stairs to get out, then it is below grade, and therefore the sq. footage is not counted.

If you are searching for a home here on Trulia or elsewhere, often in the description of the house you may read, "Additional xxx sq. ft. in the finished basement." This is because this area should not be listed with the sq. footage of the house.

Both Christopher and Alice who answered before me are very knowledgeable, though. Can anyone else confirm what I'm saying?

Usually in the Westchester area , square footage of basement is only included if the basement is finished and is considered living space. Just paint and flooring in a basement would not be considered "finished" and not be included in the square footage.
However, if you are interested in a particular home and feel uncertain about the square footage, your realtor would be most happy to give you an accurate answer.
Thanks and feel free to call me if I can help you in any way with your real estate questions.
Alice Feldman
Houlihan Lawrence Armonk
914-261-4907

Hi, Typically basements should only be calculated in the square footage if they are finished, heated, living space and also have a CO. The same goes for attic space. Now that doesn't mean the information you are reading follows that rule so you may have to inquire with the agent that posted it.

Sincerely,

Christopher Pagli
Associate Broker
Legends Realty Group
914.406.9023