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How to Calculate Roof Square Footage

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You may know the square footage of your home, but do you know the square footage of your roof? It’s a helpful number to have when working on roof renovations and repairs. Learn how to calculate roof square footage before you start your next roofing project.

Figuring Out Your Roof’s Size

The odds are good that you don’t think much about the square footage of your roof. However, if you’re ever in a situation where you need to get that information quickly, you’ll be glad you know how to calculate roof square footage. When do you need to know the square footage of your roof, and how can you quickly figure it out?

Why Would I Need My Roof’s Square Footage?

If it’s never occurred to you to figure out the square footage of your roof, you’ve probably never needed to deal with roof repairs and renovations. Most of the time, it’s not a number you’ll use very often. However, if your roof needs maintenance, the square footage you’ll be working with is an important figure to know:

  • Knowing the square footage of your roof is essential for getting all the materials you need for a roof replacement. You can’t cover the entire roof unless you know how much area you must cover.
  • A roof’s square footage can also help you work with roofing professionals on necessary repairs and renovations. For example, if you’re working with a contractor, they’ll be able to give you a more accurate estimate if they know the square footage a roofing project needs to cover.
  • Finally, knowing your roof’s square footage can help you plan for future maintenance and other home improvement projects. For example, if you know your roof’s square footage when you’re shopping for solar panels, you can purchase all of the materials you need with confidence!

How Can I Find My Roof’s Square Footage?

Clearly, a roof’s square footage can be a handy figure to have in a number of situations. But how can you get it without crawling up on the roof with a tape measure? Don’t worry, there’s a simple formula to figure out your roof’s square footage without a ladder and a risky climb:

  • Start with the square footage of your home. If you don’t have that figure available, you can find it by measuring the length and width of your home and multiplying them. If your home is not a perfect rectangle, break it up into rectangles and find the square footage of each, and then add them together.
  • Next, find the pitch of your roof. This figure is the vertical rise of your roof divided by the horizontal length of the roof. You can typically find it on blueprints or building plans. If you can’t find it there, working with a roofing professional is strongly recommended to find an accurate number for your roof.
  • Use the slope to find the pitch modifier for your roof. This number helps add accuracy to the total by accounting for roof complexity. This is most easily done with an online calculator.
  • Once you know the square footage of your home and the pitch multiplier you need, multiply them together. The final number will represent the square footage of your roof.


If you have all the information you need, it’s easy to find the square footage of your roof. If you need a little extra help, reach out to the professionals at Taylor-Made Roofing today.

If you live in southwest Missouri, contact Taylor-Made Roofing for help with everything roof-related. With over 20 years of experience in residential and commercial roofing, Taylor-Made Roofing is a company you can trust with all your roofing needs. Our family-owned business offers quality services, a reassuring warranty, and free estimates. For more information, please call us at 417-326-8778 or contact us online. We look forward to hearing from you!

P.S. You might also be interested in our blog post How to Measure a Roof for Shingles.

Fully licensed and insured, Taylor-Made Roofing is ready to take care of your roof.
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