One might think that measuring the square footage of a house for an appraisal is pretty simple and methodologically basic. Many of us think that measuring the square footage is all about taking out a measuring tape, perhaps dividing the building area into measurable square partitions, then measuring those partitions and finally adding those partitions- voila, you now have a square footage measurement!
Unfortunately that is not how it is done. In fact, measuring the square footage reminds us of an old joke about an accountant being asked in his interview as to what is the answer for 2 + 2. He quickly says, “How do you want it to be?” and then he aces the interview. Measuring the square footage is just like this. There is no one-size-fits-all type of methodology and it usually varies depending on who calculates the measurement and for what purpose of the measurement is to be used.
For condominiums and other commercial type homes, measuring the square footage is pretty much straight forward. It is generally accurate hence the records from county taxing authorities are not often questioned. However, when it comes to detached homes, there are many ways of measuring living area. Single family measurements are less likely to be revised by the county so if there have been renovations or layout changes they may not be accounted for on official documents.
Appraisers tend to use one common measurement type when it comes to measuring the square footage. They measure the Gross Living Area of your home. For condominiums, they generally just measure the interior meaning only the inside area of your unit. Some may add 6 inches to the measurement for the wall thickness. For residential homes however, they generally tend to measure the whole area of your house externally – including the walls.
How Do Realtors Measure Square Footage?
The truth is that Realtors don’t measure the square footage of your house or unit. They will likely take the values from county records. However, right now the MLS requires all agents to indicate where they obtained living area values. However, the form still allows them to indicate whether it is “estimated” or there were “other sources”.