Even if your clients do not have a list of specific needs and wishes for the home they are seeking, they likely have a general idea of what they are looking for. This might include such factors as the number of bedrooms, a ranch or two-story, or the age of the home. One item that is often important to homebuyers is the square footage of a house. But what does that include?

Measuring the square footage of a home is more than a simple mathematical formula. In other words, you can’t simply stretch your tape measure through all the rooms and add up the numbers. Newer homes should have this information available from the builder, but for older homes, you might have to provide an estimate for your clients. It’s a good idea to learn as much as you can about measuring the square footage of a building so you can give your clients an estimate that’s as accurate as possible.

When is a room not a room?

Each state has its own criteria for what you can include in the measurement of a home’s square footage. In general, a room should have a floor, walls, and a ceiling, and you must be able to inhabit it all year long. That means it needs windows that close and a source of heat. This may automatically exclude many screened-in porches, basements or attics that have not been completely finished to be living spaces.

You can calculate the square footage of any space that meets these standards by measuring the length and width of each qualifying room, multiplying those two numbers to get the square footage of each room, and adding together the totals for all those rooms. Remember that a space with walls, ceiling, floor and heat could qualify as part of the square footage, so check pantries, closets and stairwells for these features.

Getting the numbers right

You might be working in a region that separates above-ground living space from below-ground. Some states do not count below-ground space at all even if it is completely functional. This can make your calculations quite complicated, especially if a seller has a finished, walk-out basement. Additionally, a second floor or attic with low or sloped ceilings, such as in a Cape Cod, must have ceilings at least seven feet high for at least 50% of the room to be included in your measurements.

The region where you work is likely to have other specifications for calculating square footage. This number is important for your clients not just for figuring out how to arrange their furniture, but it also determines the value of the house at appraisal and the cost of insurance for the homeowner.