How to Properly Calculate Square Footage

Understanding your home’s square footage is essential whether you already own one, are looking to buy one, or wish to have one built. Calculating a home’s square footage indicates its size and whether or not it’s the ideal match for you and your family, albeit it does require some number-crunching.

calculate square footage

Importance of Understanding Square Footage Calculation

One of the most significant reasons why knowing how to calculate the square footage of a home is to make sure a house is big enough for you, your family, and your lifestyle, but there are others. Additional reasons for understanding a property’s square footage include the following:


• It contributes to how much a house is worth. The fair market value of a house can be calculated using the square footage.

• It aids in obtaining a mortgage. Most mortgage lenders demand an appraisal to approve a loan. A square footage difference could impact the value of the residence. In some circumstances, it can imply that the house isn’t worth what is asked. Thus, the mortgage could be rejected by the lender.

• It might affect real estate taxes. A home’s assessed value directly correlates to its square footage. The assessed value then influences the property taxes a homeowner must pay.

How to Determine Square Footage: What's Included?

Generally speaking, the gross living area (GLA), sometimes referred to as the usable space in your home, is what you would factor into your square footage calculation. The following characteristics often need to be present for an area to qualify as “livable space” when figuring out how to calculate the square feet of a house:


• Wallcoverings

• Ceiling

• Heating and cooling

Most frequently, you might list spaces like

• Living room

• Bedrooms (closets, too)

• Bathrooms

• Kitchen

• Dining area

A house’s overall square footage may include a finished basement. But it relies on a few things:

• Where you reside in a state

• It satisfies the criteria above for habitable space

• It has an entrance and exit (such as a door or windows)

What Gets Removed?

You should know what you shouldn’t count toward your measurement when figuring out a house’s square footage. Generally, the following are to be avoided:

• Unfinished basement

• Unfinished attic

• Patio, deck, or porch

• Garage

• Pool House

• Detached storage buildings or sheds

• Guest house or separate in-law apartment

A few exceptions apply in this case. For instance, you ordinarily wouldn’t factor in a porch when calculating square footage. You will, though, if it’s a “four-season” porch. These porches include a constant heat source and numerous windows that provide a clear view of the surrounding environment.

Finished VS. Unfinished Areas of Your Home

finished vs unfinished

Square footage may occasionally be divided into two categories, finished and unfinished. Any building section with a roof, floor, and walls is included in the finished square footage of a house. That means you cannot view the underlying framework of the walls or ceiling and the pipes and electrical wiring running throughout the house.

There must be a covered subfloor in finished areas for the floors. Oriented strand board, a material that resembles plywood, is commonly used as the base layer on the main level of a house. The basement’s base floor is typically made of concrete. Finished space must have flooring, such as hardwood, tile, or carpet, over the foundation material, regardless of what it is.

On the other hand, unfinished space is what its name suggests. It’s an unfinished room inside the house. Because the beams are not covered by drywall or plaster in the walls, the wiring or pipes are also visible. Alternatively, the room may have uncovered flooring or a ceiling. Heating and cooling probably need to be blown into finished places too. It is not “livable,” to put it another way.

One option is to calculate the square footage of a home’s finished and unfinished areas and divide it into the appropriate categories. It can help you distinguish between workable (but unlivable) space and actual habitable space.


Above vs. Below Ground (Gradient), Square Footage

Above gradient and below gradient are two more words you could hear about square footage. The ground is referred to as the “gradient.” Your above gradient square footage includes the entire building from the ground up. Everything underground is included in the square footage below the gradient.

Calculating Square Footage

square footage

Let’s now examine how to determine a home’s square footage. The procedure is rather simple. A measuring tape or a laser measure, a calculator, a pen or pencil, and some paper or a notebook should all be ready before you start.

You can start once you have all the necessary materials. As you measure the length and width of each room, proceed. The square footage of the space can then be calculated by multiplying the numbers by one another. For instance, multiplying 12 by 10 would give you 120 square feet if your room is 12 feet by 10 feet.

Your property’s total finished square footage can be calculated by adding up all of the finished spaces. You can even calculate the value of unfinished rooms or your basement and retain those as separate categories.

Calculating a Room's Square Footage with Uneven Dimensions

What if your rooms are all different sizes? There will be a few extra steps you must do, but overall, the job you presently perform will stay the same.

Let’s assume, for illustration, that your bedroom measures 14 feet 7 inches by 12 feet 6 inches. Look at the inches on the measuring tape rather than the foot side. Therefore, your dimensions would be 175 inches (14 feet 7 inches) x 150 inches (12 feet 6 inches). What you should do next is as follows:

  • Divide each figure by 12 (175 divided by 12 and 150 divided by 12) to get 14.58 and 12.5, respectively
  • Multiply the two figures together (14.58 x 12.5)

In this case, the room would have square footage of 182.25 ft.

Calculating the Square Footage of Circular Rooms

Circular rooms are rare in some households, although they do exist. You need to approach this situation a little differently. It would help if you first ascertained the room’s radius. The distance between the wall and the room’s center is that. Alternatively, you can divide the circle of the room—the distance from one wall to the opposite—in half.

Multiply the radius by itself once you get it. For instance, if your room has a radius of 10 feet, you will multiply 10 by 10 to get 100. Then multiply that result by pi (3.14). Your circular room has a 314 square foot square area.

Standards for Calculating a Home's Square Footage

home's square footage

Here are a few more ideas to consider that can make figuring out a home’s square footage simpler:

Having a visual can be helpful for some people. A rudimentary design of the house can make it simpler to combine the rooms—you don’t have to go fancy with it. Additionally, it can ensure that you don’t overlook any of the rooms.

• SELECT THE ROOMS YOU WANT TO MEASURE. Select the rooms you want to measure after you have your floor plan. Usually, those are the parts of the house that have been finished. If you want to know how big the unfinished spaces are, you can also measure them. Make sure to record those dimensions in a different category if you measure the unfinished portions of the house, such as the basement, garage, patio, or detached constructions.

• ALWAYS MEASURE YOUR STAIRS. The stairs are a frequently forgotten factor when calculating square footage. If your house has (or will have) a staircase, count the number of steps by multiplying the depth and width of each step. That amount should increase the home’s total square footage (completed).

Does Square Footage Affect Your Plans to Build a Home?

It is simple to determine a home’s square footage, which reveals how much usable room there is. The value of a property and the amount of property taxes you have to pay are affected by that number.

Even if a home’s average square footage affects some factors, you shouldn’t obsess over it, especially if you’re planning to hire a builder to create a brand-new house. The price per square foot can differ significantly from one builder to the next.

Things become a little more difficult when you’re building a house, but we’re here to assist you in making wise decisions and navigating the financing process with a little less suffering. It can be challenging to obtain a construction loan to construct a new house on your property. However, Builder Loans will be there for you at each stage of the financing procedure. 

Even if your credit isn’t good enough to purchase a new home, Builder Loans will connect you to incredible financial experts that can aid you in taking the necessary financial action. Your dream is to build a home on your property, and Builder Loans is prepared to serve as your guide to alleviate some of the stress that comes with organizing your finances.

A construction loan is helpful when building a new home since costs are prone to change, and unanticipated expenses may appear at any time. For additional information, visit