An agent's buyer measured the rooms on our listing. Below are the measurements they reported with their calculation of the square footage:

Living Room 16x12 = 192

Kitchen 10x8 = 80

Bedroom 2 10x10 = 100

Master Bedroom 12x11 = 132

192+80+100+132 = 504

The problem is they are only adding the sizes of the rooms but left out closets, the bathroom, and halls. Architects and appraisers often calculate square footage by using exterior walls. When the entire floor plan is measured including the walls, the square footage is 800 sf.  

So what areas of a home should be left out? Unfinished areas such as garages, balconies, decks, and basements (even if they are finished). Finished attics are included if they have at least a 7-foot clearance from the floor to the roof pitch. 

A property's square footage can be a general guide to use in comparing properties against each other but cannot account for location, floor level, natural light, ceiling height or condition.