Is it time for a roof replacement? Are you trying to figure out how much you’ll have to invest in your new roof? 

If so, you’re probably overwhelmed trying to learn everything that goes into the cost of your roof replacement. To help you understand the size of your roof investment, you first need to know the size of your roof. That’s why we’re going to break down how to measure your roof’s square footage. 

The team at Bill Ragan Roofing has been repairing and replacing roofs in Nashville and surrounding areas since 1990. We take extreme pride in everything we do, especially our workmanship. 

By the end of this article, you'll learn how to calculate your roof's square footage and 3 more things that impact the cost of your roof. 

How to measure your roof’s square footage 

The square footage of your roof has a huge impact on the cost of your replacement. It affects a number of cost factors, including the amount of materials used, labor, and time. 

Be aware, the only way to get a 100 percent accurate measurement is to have a local roofing contractor come out to professionally measure your roof and give you a quote. However, I can give you the calculations to get a rough measurement of your home’s square footage.

Figure out your home’s footprint

If you use the square footage of your home, you’ll only get a vague idea of what the square footage of your roof is. That’s why you have to figure out your home’s footprint. 

A person of average height will have a stride somewhere between 2 to 2.5 feet. To figure out your home’s footprint, you can step off (you can also use a measuring tape) the dimensions of your roof by counting the steps you take to get the length of your home. You will then step off the width of your home. 

After stepping off the length and width of your home, you’ll multiply the two numbers to get your home’s footprint. 

Length x width = your home's footprint

Your calculations are going to be off, but measuring this way can give you a basic idea of your home’s footprint. Keep in mind, square footage of a house does not equal the square footage of a roof.

Keep the slope and complexity of your roof in mind

You have to keep in mind the makeup of your roof when doing the calculation for the square footage. The steepness and complexity will change the number you multiply the footprint by. 

For example:

For an easy up and over, walkable gable roof, you’ll multiply the footprint of the roof by 1.3 to get the square footage of your roof. 

For a hip roof with a low slope, you'll multiply the footprint of the roof by 1.4 to get the square footage of your roof. 

For a steep and complex roof, you'll multiply the footprint of the roof by 1.6 to get the square footage of your roof.

Calculate the square footage of your roof 

Now that you thought about the slope and complexity of your roof, you’re ready to learn how to calculate the square footage of your roof. 

To get a rough estimate for your roof’s square footage, you’ll use this equation:

(length of home) x (width of home) = (footprint of your home) 

(footprint of your home) x (slope and complexity) = (square feet of roof area)

For example, if you have an easy up and over, walkable gable roof and a house that measures 56 feet lengthwise and 28 feet widthwise, your calculation will look like this:

  56' (length)

x 28' (width)

1,568' = (footprint of your home)

x 1.3  (for an easy up and over, walkable gable roof)

2,038 = square feet of roof area

Using this equation won’t be 100% accurate, but knowing your roof’s square footage is a great jumping-off point to learn how much you’ll have to invest in your replacement.

3 more factors that impact the cost of your replacement 

Square footage has a huge impact on the cost of your new roof. However, there are more factors that impact the cost of a roof replacement.  

1. The type of roof you want

The type of roof you want will have a big impact on the cost of your roof replacement. There are a variety of different types of roofs for you to choose from based on your budget and the look you want. 

If you’re on a tight budget and looking for an affordable roof, an asphalt shingle roof might be right for you. But if you’re looking to upgrade to a longer-lasting and sharp looking roof, there’s the standing seam metal roof. 

Asphalt and metal are two of the most commonly seen roof types, but there are also premium shingle roofs that come at a premium price. These roofs give you a unique look that really stands out. These premium roofs include cedar shake, slate, and tile. 

The premium shingle roofs can get expensive quickly and be more than triple the cost of an asphalt shingle roof.

2. The labor and time to complete the job

Labor and time are two of the main factors a roofing contractor considers when calculating the price of your new roof. If anything takes time and labor, it will show up in the final cost of your roof replacement. 

The labor cost of each man on a crew is based on their skill level, experience, and how much they can get done in a day. The labor cost will vary from contractor to contractor. 

The time it takes to complete the job is also a factor. The more time a roofer has to spend on your roof and property will always affect the price of a new roof.

If the roof is complex and hard to access, it take longer and more labor to complete. From tearing off your old roof to cleaning up your property after the job is done, if it takes manpower and time, it’s going to impact the cost of your new roof. 

3. The operating cost of your roofing contractor

Every roofing contractor has operating expenses to keep their business going. These operating costs will always factor into the price of any roof work that needs to be done. 

Some common operating costs are:

  • Building cost and utilities, shop and truck yard
  • Advertising and promotions
  • Vehicles (fuel and insurance)
  • General liability insurance
  • Workers compensation insurance
  • Licenses and bonds
  • Training 
  • Payroll and payroll taxes
  • Taxes (Federal and local government)

These are just some of the fixed operating costs that it takes to run a business. No matter if a roofing company does a simple repair or replaces 10 roofs, these are the costs that have to be paid every day. No matter what work you get done or what service you need, operating expenses will always factor into an estimate or final cost.  

What else impacts the cost of your new roof?

Now you know how to roughly calculate your roof’s square footage and 3 more factors that impact the cost. Remember, the only way to get a 100 percent accurate measurement is to have a local roofing contractor come out to professionally measure your roof.

Knowing your square footage and the 3 other cost factors lays the groundwork for learning the size of your roof investment. However, there are even more factors that impact the cost of your new roof besides what’s listed in this article. 

To understand where your hard-earned money is going when you invest in a new roof, we broke down the 9 factors that affect the cost of your new roof. 

The team at Bill Ragan Roofing has provided high-quality roofing services in the Nashville area since 1990. We give you an experience rare in the roofing industry with our workmanship and customer service. That’s why we’re proud to offer you a lifetime warranty. 

To learn what affects the cost of your replacement, check out 9 Factors That Impact the Cost of Your New Roof.

roof cost calculator