If you’re looking into replacing your roof, you’ve probably come across the term “square.” It’s a common roofing term used by roofing professionals to determine how much roofing material they will need in order to cover your roof. So, what is a square in roofing? A square in roofing is used for everything from shingles (or tiles, shakes or any other exterior roofing material you choose) to underlayment and decking.
Using this unit of measurement makes it easier for a roofer to calculate the square footage of your roof. Roofing professionals think of your roof as a series of planes, or surfaces. On a typical home, you’ll have a “plane” on the back side of your home and one on the front. Homes with dormers and other architectural features may have more than just two planes. These planes are divided into squares, which roofers use to determine the square footage of your roof.
How many square feet in a roofing square?
A square in roofing measures 100 square feet. It represents a 10-foot by 10-foot section of your roof. So if a roofer tells you your roof is 20 squares, you would multiply 20 by 100 (the square footage of a square) to determine that your roof is 2,000 square feet. Likewise, if you know your roof is 2,000 square feet, you can divide that number by 100 to determine that your roof has 20 squares.
How does a roof’s pitch affect square footage?
Calculating the exact square footage of your roof can get a bit complicated when you consider your roof’s pitch. The steeper the pitch (which is a ratio of how many inches the roof rises per foot), the more square footage you’ll need to cover. That means you may need to purchase an extra bundle or so in order to accommodate for your roof’s steeper pitch.
You can use Instant Roofer’s handy roof pitch calculator to quickly determine the exact pitch of your roof using AI-powered map technology. But if you like to kick it old school, and you know your roof’s pitch, this table will help you calculate a pitch-adjusted square footage on your own using a multiplier. Once you calculate your roof’s flat square footage, simply multiply that number by the multiplier shown here
| Pitch | Multiplier |
| 1/12 | 1.0035 |
| 2/12 | 1.0138 |
| 3/12 | 1.0308 |
| 4/12 | 1.0541 |
| 5/12 | 1.0833 |
| 6/12 | 1.1180 |
| 7/12 | 1.1577 |
| 8/12 | 1.2019 |
| 9/12 | 1.2500 |
| 10/12 | 1.3017 |
| 11/12 | 1.3566 |
| 12/12 | 1.4142 |
How to Determine the Amount of Roofing Material to Buy
Shingles are sold in bundles. Bundles of shingles are long, flat packs of tightly wrapped shingles that make it easier for your roofing contractor to lift them onto your roof in a safe and secure manner. They’ll use a crane to lift the bundles onto your roof either the morning of or the day before your roof is replaced. If you’re wondering what is a square in roofing, this crucial measurement will inform how many bundles will sufficiently cover your home. You can also use our free and accurate roofing calculator to estimate the bundles, felt, and rolls you’ll need for your next project too.
How many bundles of shingles in a square?
The number of bundles of shingles you’ll need for each square depends on the size and type of shingles, as well as the particular way the manufacturer bundles them.
How many shingles are in a bundle?
In our research, we found that there are most often between 20 and 40 shingles in each bundle. And most of the time, three bundles equals one roofing square.
So using the 2,000-square foot roof in the above example, you would need 60 bundles of shingles to cover your roof: that’s 20 squares multiplied by 3 bundles per square (20 x 3 = 60).
Average Price Per Square For Roofing
By now, you know the answer to the question, what is a square in roofing? And you probably even have a rough idea of how many squares you might need for your roofing project. But in order to get a rough estimate for your total roofing expenses, you’ll need to know the average price per square for roofing. Here’s a table that outlines the average price for different types of roofing materials.
| Roofing Material | Price Per Square |
| Three-tab asphalt shingles | $80 to $130 |
| Dimensional shingles | $100 to $250 |
| Aluminum | $300 to $900 |
| Copper | $900 to $2,000 |
| Stainless steel | $500 to $1,300 |
| Zinc | $500 to $1,000 |
| Tile | $300 to $2,500 |
| Wood shake | $200 to $900 |
| Slate | $600 to $1,600 |
As you can see, the price per square for roofing varies greatly depending on the type of material you choose for your home. When replacing your roof, you’ll also have to factor in additional expenses for things like labor, underlayment, decking, nails and other fasteners, flashing, removal of your existing materials, and other expenses as well. So knowing the average price per square is only a small part of your total expense.
How To Measure a Roof Accurately
If you’d like to perform your own calculation for comparison, follow these steps to determine the square footage of your roof.
- Identify each of your roof’s planes. A plane is basically an individual surface of your roof such that flat roofs have one plane, a gable roof has two planes, and a roof with dormers will likely have four or more planes.
- For each plane, measure length and width. Multiply these numbers to get the square footage of the plane.
- Add the square footage amounts of each plane to get the total square footage for your home.
- Divide this number by 100 to get a rough estimate of the number of roofing squares.
- Use your roof’s pitch to determine how much extra material you will need.
It’s critically important to call a roofing professional if you do not feel safe accessing your roof. A lack of experience can lead to a devastating accident, which is why most roofing jobs should not be attempted by anyone but a professional. Instant Roofer can help you find a roofer in your area who can help you measure and install a new roof on your home.
Fact checked by Christin Perry – 3/8/2024