Updated February 26th, 2019

There is certainly a lot to consider when selling or purchasing a home. One of the most critical factors that a buyer should understand when evaluating properties is the property’s square footage.

Because there is no exact science to measuring square footage, an accurate assessment is even more important, as square footage can be one of the leading factors that drive the value of a home. We highly recommend the assistance of an experienced real estate agent for this step in the sale or purchase of your home.

The Math Behind Square Footage

To begin with, a good framework for buyers and sellers alike is to think of each room in your house as a rectangle. Assuming you have a rectangular area will allow you to use the square footage calculation, length x width = (ft2). If you have an oddly shaped area, such as an L-shape, split it into square or rectangular sections and treat them as two separate areas.

Here is a simple, five-step process for measuring the square footage of your home:

  • Measure the length of the room
  • Measure the width of the room
  • Round up to the nearest .5 linear foot
  • Multiply each space’s length by its width.
  • Add up the measured sum of each room to find the total square footage. Be sure to round off to the nearest foot.

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Know Which Rooms to Measure

After you understand the math behind square footage, you then must understand which areas are included in the overall calculation. Do not include garages, patios, porches, external staircases, or other rooms without first knowing the specific requirements for each of them to be included. Another good resource any buyer or seller must use to determine the exact square footage can be found in a home’s building plans. For this information, contact your local permit agency or records office.

Here is a list of rooms that can add to a home’s square footage:


Depending on the circumstances, a home’s basement may or may not be considered when calculating the livable square footage of a home. As a general rule, any structure below grade, or underground, should not be included in the total area. These standards will vary by stage along with the definition of “below grade.” Additionally, the only allowable space for walkout basements is the above ground square footage.

Whether a basement is finished or not has little to do with its inclusion in the home’s square footage. Basements can still add value to the home and are often showcased online. On average, finished spaces are in higher demand than a space that needs renovation.


To include an attic in a home’s square footage count, it needs to be finished and include at least seven feet of clearance space. Buyers will commonly find attics advertised in the home listing even when the space is not considered livable.


If a porch is covered and enclosed, sellers can include them into the square footage count. Heating and cooling systems on porches must also be the same as on the rest of the home. A good example of a covered, enclosed porch is found in a sunroom.

Outbuildings and Extras

Garages, outbuildings, pool houses, and external guest rooms can also boost a home’s value. Despite this, these areas should not be included in the square footage calculation unless a connection exists with the main house. As a buyer, consider these as “bonus” rooms.

Ask for Guidance from a Real Estate Expert

Considering the importance of square footage, first-time home buyers should not be afraid to reach out for help. There are appraisers that specialize in valuing homes in most areas.

For sellers without an agent (commonly known as FSBOs), a well-qualified appraiser is essential for accurately advertising the property. Additionally, seasoned real estate agents are generally familiar with a home’s spacing and can often estimate square footage without a tape measurement.

A final source of information can be found in the city’s building department, where home builders must submit square footage in their documentation for plans and permits.

Be Honest

No matter which method you use to determine the square footage of your home, remember to be as accurate and honest as possible. The size of a home is a key factor for home buyers, and a large discrepancy could hinder or lose your sale. As a seller, it is up to you to make sure that your house is being represented correctly.

Have Questions?

Clever has knowledgeable and experienced full-service agents all over the country that would be happy to help answer your questions. Best of all they can sell your home for a flat $3,000 or 1% over $350,000. Say goodbye to traditional real estate commissions and contact us today!