There is little concensus on how square footage should be calculated. Is it possible there is a legitimate reason for the discrepancy? The generally accepted way to calculate squate footage in our area is to measure the OUTSIDE of the living space (heated, finished, not porches, not garage, not attic unless finished, not basement even if finished, etc.), then subtractions are made for two story spaces that are material. They generally don't subtract for foyers that are two story, but would subtract for a room that had a ceiling going to the second floor level. Subtractions are not made for space within the living envelope that is not livable (insides of walls, etc.).

My house is somewhere between 3798 (my calculation) and 4300 square feet (tax assessor). There appraiser said it was somewhere in between. That's a pretty big difference, IMO. If I was going to sell I guess I could use the higher square footage and get away with it.

The square footage could be off because of the software a builder designer uses. We ran into that when the GC was finalizing our plans. We'd fought to get the square footage down, then when he gave us the plans for final approval, they were back over 3000 sq. ft. All the porches and the carport had been added in twice. Turns out that with many programs, if those areas are not properly designated as exterior spaces, they are counted in the square footage for interior space.

Since I had been using a design program to come up with preliminary plans and had run into this problem before it was easy to figure it out.

Somebody better figure out a way to standardize it if they are going to propose something like is proposed in the linked article below. (Which I would hope has no chance of passing).

Here is a link that might be useful: Bill to bar tax credit on big houses

Thanx for the feedback, you guys are so helpful!! I have been poking around here for several months and just started posting questions recently I gotta say this site has greatly increased my knoledge and awareness of the home building process, I wish I found it a few months sooner. I stay up for hours reading thread after thread. I break ground this week YEEEE HAWWWW!!!. My GC sais the house is 3700 SF. Counting the foyer twice I still come up 100 SF short. I measured out my current home which is 30 years old and it came up a solid 100 SF short also (Based on town) ! I guess this is not only common but been going on for a while!

I see Congressman Dingell has also given the official definition of "McMansion": any private home of more than 3,000 sf. (It's so reassuring that there's no question or problem our elected minders don't have an answer to.)

Very curiose how large a home Congressman Dingell lives in,Probably an 720 SF apartment LOL. Hipocrate.

Not to hijack your thread but we wondered how square footage is calculated as well. We submitted our plan to the county and it clearly states on the blueprints 4292 Sq. ft. Yet, the tax website has us at 4377. I know it's not a huge difference but since we pay per sq. ft it bugs us. How does the tax assessor get his numbers? I assumed it was right off the plans we submitted. Anyone know?

Lindy