Agree with kudzu9, In my area we market the interior sq footage (living area). There is a field for total building area, but comparisons are made on the living area and not the total building area. Your appraiser will use more than just square footage to select comps.

Thank you for your comments, your information was helpful.

A little puzzled, as my understanding is - sqft of a house is counted finished, livable space but determined by exterior measurement.

If two houses have same exterior sqft. House A has more interior walls to make more, but smaller size rooms, House B one only has a few large size rooms (with less interior walls), which house is bigger?

azmom-

I should have stated that my answer above is based on what I understand to be the standard in my area: square footage is livable interior space. However, I am sure standard practice in other areas might be based on exterior measurements, which has the advantage of being easy as you don't have to add up the areas of all the interior spaces. However, that is a less precise and less reliable method that can allow manipulation. Another reason to use interior space is because it leads to fair comparisons between, a house and, say, a condo in a multi-unit building with shared walls. In any case, it's important to confirm what the square footage is based on for any homes you are looking at to make sure that you are comparing apples to apples.

azmom

Appraisers do measure the outside and make the appropriate calculations for square footage. It is much more accurate to measure the outside and deduct for non-living area space than to try to get there by adding interior dimensions. An appraiser also measures room sizes, but the sq footage is determined from the exterior measurements.

Total square footage is larger than living area. Total square footage includes building area that is not living area, for example garage spaces, portico spaces and patio spaces. If two homes have the same square footage it doesn't matter if house A has more walls unless the floorplan becomes non-functional (in your example).

Appraisers only compare to the same property type - they would not cross compare a condo of the same size with a fee simple single family home to determine value.

To the OP I hope you were able to show the builder that total area is not the same as living area:)

Here's how it was listed on my plans. The total square footage is considerably more than the actual livable square footage.

"I've heard it defined as the heated (and cooled, if appropriate) space."

= "Conditioned" Space

As an appraiser, I start with exterior measurements of the subject property. I use this type of measurement to compare against similar exterior measurements of recent sales that I am considering for comparable sales. I also measure additional spaces, basements, garages, porches, patios and out buildings. An unfinished, unconditioned space would not be included in the calculation of finished space. It would be treated separately. I would find a unit of comparison that is similar in utility for comparison.

If a property has a vaulted foyer or series of rooms with large vaulted spaces that take up the entire second floor, I'm going to reduce vaulted space in my final square footage calculation by 50%. Attic spaces are not generally included in calculations. There are exceptions to this. From the original post, it doesn't apply in this situation.

The builder has to pay for attic space and vaulted ceiling. Boards, drywall and roofing shingles cost money. That's why they want to include it in their marketing. I won't get into cost analysis. That's another subject for another day.