Large home
Calculating square footage and cubic footage of a house is important for current and prospective homeowners for many reasons. Finished and unfinished space can make a huge difference on a home’s value and how much square footage you really get for the asking price. Here are a few factors to consider when measuring your home.

How to Calculate Square Footage

To determine square footage simply measure the length of the room and multiply by the width. That’s it.

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Buying & Selling Square Footage

For real estate advertisings and listings, most agents determine square footage by measuring the exterior dimensions of the house.

To calculate square footage in this way, you would measure corner-to-corner or end-to-end. Then take the sum of the exterior length of the house and multiply by the sum of the exterior width. Real estate agents often measure straight corner-to-corner, then deduct non-heated spaces, and add heated spaces whose footprints exceed the end-to-end measurement.

Finished vs. Unfinished

When buying or selling, it’s important to know which rooms count towards the total square footage and value of your house. The standard rule is that any rooms that are finished can count when calculating square footage and cubic footage of your home. Finished spaces are those that are heated and cooled in the way as the rest of the house. This means that, for example, if your enclosed porch is only heated with a space heater when the rest of the house is centrally heated, your porch cannot count towards total square footage. So, if you want to add more value to your home, you may consider adding central heating and cooling to your enclosed porch. This ensures the cost of your home reflects the most finished space possible.

Finished basements have their own set of rules, and even those can be subjective when calculating square footage and cubic footage. Typically, if the basement is heated and cooled in the same manner as the rest of the house, is carpeted or floored in the same way as the rest of the house, and has an entrance to the main floor it can count in your home’s total dimensions. If it doesn’t meet all three criteria, it may still be possible to state your basement square footage separately in a listing. If you’re selling your house and have a basement, it’s wise to consult with a real estate agent to determine if your basement should be included in the home’s total measurements.


Whether or not you like the idea of renovating your house, know it can go a long way toward increasing your home’s total value especially if you have a few unfinished spaces. If you sell, unfinished spaces do not count when calculating square footage and cubic footage of your home. If you want to be reimbursed for those spaces, it can be well worth the cost of finishing them. To qualify as finished, spaces must be carpeted or floored as well as heated and cooled. They must also directly attach to the main house. If you have a finished garage or pool house that is detached from the main living space, they may not count toward total square footage but can be listed separately.

Unfinished spaces are also important points of consideration for buyers. If you’re willing to renovate them, you can dramatically add value to the home when it comes time to sell. Perhaps the house you’re looking at only lists 1100 square feet, calculating square footage and cubic footage only for the main, finished living spaces. You may find when touring the home that it also has an attached, unfinished 800 square-foot basement. If you’re willing to fix up the basement, you can get a great deal on the home. You’ll get all of that space without actually paying for it.

If you have done any past expansions, it’s important to factor in those additions when calculating square footage and cubic footage of your home. Buyers can also consider purchasing a home with smaller dimensions and then, if the property allows, adding on new space later to increase its value.

Growing Families

This may seem obvious; however, it is vastly important to factor in your family size when considering the dimensions of a new home. A two-bedroom house that measures in at 1200 square feet may be sufficient for you, your spouse, and perhaps a guest, but you may find yourself cramped for space if you plan to have children. Calculating square footage and cubic footage is important to ensure your new home allows for room to grow. Again, you may be able to look for homes with some unfinished spaces to make it easier on your wallet at the time of purchase. You can finish those spaces later to accommodate children as your family grows.

Renting Space

Just as it is important to know your home’s square footage if you have a growing family, it’s also important to know if you plan to rent any of your space out to tenants. If you plan to live on the same property with tenants, you’ll need to ensure there is both enough space for you as well as the number of renters you expect to have. Calculating square footage and cubic footage of all of the living space as well as specific rooms in the home is imperative for anyone who is considering housing tenants. Unfinished spaces can come into play again in this situation. You can save money upfront and increase the home’s value over time by adding renovated space to accommodate more tenants.

Other Factors

There are a few other things to consider when comparing dimensions of homes or measuring your own. Furniture and decor are worth consideration because they can take up a large amount of floor and wall space. Calculating square footage and cubic footage is important in this situation to ensure the property doesn’t just sound roomy, but that there really is enough physical floor and wall space to comfortably fit all of your furniture and decorations. For example, you might find a house listed at a spacious 2,000 square feet only to discover that most of that space comes from high walls and ceilings, leaving little floor space for furniture.

Whether you’re buying or selling, these are a few reasons that calculating square footage and cubic footage is so important for current and prospective homeowners. Consult with a real estate agent to ensure you are getting the most value possible for your home.

Carpet Installation

Once you’ve determined the simple square footage of the room you’re carpeting, you will need to add an extra 10 percent to your carpet order for cutting, waste, and staggering the carpet joints. A 10 x 10 room has 100 square feet. You would need to order 10% more or 110 square feet of carpet. Carpet installation generally requires padding that comes in 100 square foot rolls.

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  1. Susie, May 28:

    When I measure length and width to determine the house’s square footage, do I multiply in inches or feet?

  2. bill, June 15:

    Do you include Bay windows to the square footage? For example a Bay window that extends 1 foot out from the and 4 feet wide. Is that another 4 sq. ft.? May seem minimal but we have 3 of them and they would put us over 2000 sq. ft.

  3. John, July 26:

    Bill, the article I just read said you include bay windows if they are supported by foundation. Window seats would not be counted.

  4. Johnny Dowell, September 14:

    I am trying to figure the sq. ft. of a house. I know that the size of house is 31’8″ length & 42′ Wide which I figure is approx. 73 sq. ft. but wasn’t sure how to figure the height which is 10 ft. Are you able to help me?

  5. Shawn Moore, September 16:

    I have a load of hand made flooring. I would like to us it in a large room, but not sure if I have enough. The boards run 3.5 inches by anything from 5 inches to 6 feet. I don’t remember how to figure the square footage on this. I know the room is 245 sq. ft.
    I was doing the (example here) 3.5″ x 46.625″=163.1875 NOW how do I get it to square feet or foot and inches?
    Thanx for the help!

  6. Tom E, October 27:

    When calculating sq in to sq ft divide the sq in by 144 to get sq ft.
    A sq foot is 12in by 12in or 144 sq in.
    So your 1 board example is 1.133 sq foot.
    to find out the entire room add up all the sq in then divide by 144 to give you the total sq ft. Don’t forget to allow for waste, deduct 10 to 20%.

  7. Julie Hellwig, January 18:

    I just cleaned an empty house for $60 dollars it was 1,132 sqft I’m trying to figure out how much I made by sqft I know it wasn’t much. But I have another of his house which is only 1,008 and he wants to charge me way less to clean he said it isn’t as big as last house!

  8. Susan, March 23:

    Why does the square footage on the listing sheet differ from the actual square footage of the house?

  9. jonathan, March 28:

    if I am building a square house, with an open square garden in the middle, do I subtract the square footage of the garden, from the square footage of the house ?

  10. T, April 6:

    Do closets and hallways count toward the total square footage of a home?

  11. elaine, May 13:

    if a room is 12’4″ x 16’8″ how do you figure square feet.

  12. Rajesh, January 20:

    I have booked a apartment with 1591 Swetha feet, but when I did a basic calculation of multiplying L *B of all rooms ( square or rectangle) and then sum it up the total is coming to 1080 so feet.., if this is the carpet area then how do I calculate the total area to arrive at 1591 Sq feet

  13. Dee, July 1:

    I am purchasing a 12×20 wooden storage building to make into a cottage just for me. Was wondering about an estimate and if we need to hang walls 1st there is no loft or attic only me.

  14. Frank, October 19:

    How to I calculate the square footage of my house the main structure is 73’ by 42’ with a HVAC porch that is 10’ 15’ and a breezeway that is 20’ by 39’ and a finished HVAC garage hand guest room that is 30’ 30’ all but the porch have a second floor and the main house has a finished basement.

  15. Alan, November 7:

    Also need cost of wrapping 12 standard Windows extra framing and wrapping house just labor pric

  16. DyAnne Wilkerson, April 8:

    I need to know if I have 52 feet – how many square feet is that ?

  17. Jim Dasher, May 29:

    @Frank, Oct. 19: Main House: 73′ x 42’= 3,066′ x 2 (2nd level) = 6,123′.
    Add: HVAC Porch: 150′. (Your ‘breezeway’ does not count as living space.)

    If your garage is 2-story, and 30′ x 30′ per each level and the top level is your ‘guest room’, add: 900′. (NOTE: ‘Garage areas’ are NOT living space! Guest rooms are.)

    Main House: ……… 6,123 sq. ft. (if two story)
    HVAC Porch: ………… 150 sq. ft.
    Garage ‘guest room’: 900 sq. ft. (If second floor of garage)

    Total square footage based on ‘your’ information: 7,173 sq. ft.

  18. Veronica, August 25:

    What is the square footage for a room that is 13’X 14′ in size?

  19. John, September 29:

    Does the footprint of exterior & interior walls count? The footprint of a walk in fridge? Is the footprint of a stairway plus the footprint of an under stairway storage area add up as two separate entities or Is the footprint of the vertical column measured singularly. I understand garages even if finished don’t count, but do storage closets accessible only via the garage count? If an attic is otherwise finished but not commonly accessible (e.g. via a pull down attic ladder) does it’s area officially contribute to the home’s square footage? Does an elevator’s footprint contribute to a home’s official square footage? I’ve (tried) to read various building codes but only end up more confused.

  20. John, September 29:

    Addendum… Other areas I’m curious about is if walk in pantries, kitchen island area, and the footprints created by counter space & cabinetry, etc. add to a home’s official square footage.

  21. Allen Garrison, December 15:

    They only count livable space in the square footage of the inside.

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