How we measure the gross living area of a home is important, but there is little consistency. Different websites may use different numbers for the same home, primarily because they tend to have only one field for square footage.
Below, I’ll write about Fannie Mae’s new rules for measuring homes, but it’s up to each real estate website operator which number it uses for square footage. For example, the web page that we create for each Golden Real Estate listing has only one square footage field, so I choose to display finished square footage. The MLS has fields to distinguish between finished, unfinished, basement, above-grade, and total square feet, as shown below, and all those fields are uploaded to every consumer website, but I haven’t found any consumer website which displays all those fields.
Zillow is an example of a website which features only the total square footage in each listing, even if half that area is unfinished basement space. It doesn’t show the breakdown of finished vs. unfinished space or basement vs. above-grade space unless you click on a link titled “See more facts and features.”
Trulia, which is owned by Zillow, has a link “See all” which lists “finished area” if you scroll down far enough, but that’s all. I find this ironic, because both Trulia and Zillow provide a ton of information not found on the MLS, yet they downplay or omit the most important detail of all — the breakdown of square footage.
Redfin, which, like Trulia and Zillow, gets the full feed from our MLS, also features only the total square feet and has no link that I could find which displays a breakdown. And, like both Trulia and Zillow, Redfin prominently features “price per square foot,” but that figure is based on the total square feet, which can be really misleading.
Golden Real Estate’s website, like those three, gets its active listings from the MLS, but our display is managed by the MLS, and all listings on our website use the finished square footage number, which is, I believe, the most useful single number to use. But, once again, there’s only one field for displaying square footage.
The MLS has its own consumer-facing website, www.REcolorado.com, where you can search for listings. On that site, the total square footage is featured, but scroll down and you see this very thorough breakdown of square footage:
On other websites, you’d only see 3,166 square feet and $271/sq. ft. for the listing in this example.
The numbers displayed on the MLS are entered by the listing agent. Our sole obligation in providing them is to indicate the source. It could be from public records, or it could be from a prior appraisal. We could also measure it ourselves, but that is really unlikely. The only requirement is that we disclose the source. The safest choice is public records, but those numbers could be wrong.
Fun fact: Square footage of a home, by whatever standard, is measured from the outside of the exterior walls, not the inside.
Lenders, of course, want to know that the square footage is accurate and consistent, so recently Fannie Mae mandated that all appraisers follow the ANSI (American National Standards Institute) standard, which can result in appraisals which come up with different numbers than in the MLS listing on which the buyer relied.
The ANSI standards don’t allow for space with ceiling heights under 7’ to be included in the gross living area, and the square footage of staircases can only be counted on the level from which the staircase descends. Also, if even part of a level is below grade, the entire level has to be counted as “basement,” which directly conflicts with MLS rules which say the lower level of a bi-level or tri-level home (which is at least partially below grade) can be counted as above-grade square footage.
Complicating matters, appraisers must measure properties using the ANSI standards, but they have no choice but to rely on MLS measurements for the comps they cite in an appraisal, which were surely not done to ANSI standards. The technical term for this is “apples and oranges…”
There are three different square footage numbers for every MLS listing, and here is a quick tutorial on REcolorado’s rules for measuring square footage.
Above-Grade square footage used to be called “Main” square footage. As the new name suggests, it does not include basement square footage. But that begs the question, “what is a basement?” In a split-level home, the lower level, which is often below grade, is included in the “above-grade” square footage, since there is frequently a basement below that level. In a “raised ranch” home, the lower level is included in “above-grade” square footage for the same reason. (A “raised ranch” is defined as a home where you have to climb a flight of stairs to get to the “main” level. The “main” level is defined as the level containing the kitchen.)
Finished square footage includes all the finished square feet, whether in the basement or above-grade. If the basement is unfinished (or there is no basement), this number will be the same as the “Above Grade” number.
Total square footage is what the name suggests, whether finished or unfinished.
All three of these numbers will be different when a listing has a partially finished basement.
Golden Real Estate's Blog 