What is The Size of a Square of Roofing Shingles?

How big is a roofing square? This is one question that most homeowners usually ask when installing a new roof on a newly built house or replacing an existing roof. Knowing the roof’s area will help you determine the correct quantity of roofing shingles needed.

When you’ve settled on asphalt shingles, you’ll need a professional roofing contractor to help you install them. But before you hire anyone, you can estimate the size of shingles your roof needs. That will be easier when you know how big a roofing square is.

How Big is a Square of Roofing Shingles?

Simply put, a roofing square of roofing shingles is 100 square feet. This measurement unit is often applicable in the roofing and construction industries. However, you can use it to determine the cost and the number of shingles you should buy for your house.

To determine the number of roofing squares on your roof, you first calculate the roof’s total square footage. That means you have to take the planes’ measurements on the rooftop and calculate the whole area. You’ll then divide the figure by 100.

The most challenging part of determining a roof’s total square footage is taking accurate measurements. You’ll need to know the roof’s slope and the size of all planes on the roof. It might also be tricky to access the roof, especially when the design is complex.

Calculating the square of roofing shingles doesn’t have to be tricky. You can hire an expert roof contractor to help you do the job. Even if you have all it takes to determine the number of roofing shingles required, there are steps you must follow before that.

How to Calculate the Number of Shingle Bundles for Your House

Determining the number of roofing shingles required by your house can be easy when using a proper method. You also have to consider the number of extra shingles you need for overlaps and waste. So, how do you calculate the number of roofing shingles?

Here is a step-by-step guide to help you find the number of roofing shingles you need.

  1. Calculate your roof’s total square footage
  2. Determine the number of roofing squares on the roof
  3. Measure the pitch of the roof
  4. Calculate the number of shingle bundles your roof needs

Step 1: Calculate Your Roof’s Total Square Footage

To calculate the roof’s total square footage, you have to go to the rooftop and measure the lengths and widths of the roof planes. But before doing that, you have to prepare adequately by assembling all the necessary tools and equipment.

Secure a stable ladder and wear essential safety gear, including work boots with improved traction. Don’t forget to carry a tape measure to help you take accurate measurements. Get a pen and a notebook for recording the measurements.

In order to calculate the total square footage of the roof:

  1. Measure the length and width of every plane (if rectangle) of the rooftop, then multiply the length by width.
  2. If the roof has a complex design, look for the formula for calculating the area of the roof configuration.
  3. To get the total square footage, add the square footage of all the planes.

Pro Tip: As you take measurements, note the number of skylights, chimneys, and other obstructions on the roof. Such features may increase the number of planes on your roof.

Step 2: Determine the Number of Roofing Squares on the Roof

After calculating your roof’s total square footage, you have to convert the figure into roofing squares. It’s the easiest part of the calculation process. You need to divide the overall square footage by 100 to get the number of roofing squares.

For instance, if the total square footage of a roof is 1,800 square feet, consider dividing it by 100 to get 18, the number of roofing squares on the rooftop. 

Step 3: Measure the Roof Pitch

When estimating the number of roof shingles, you’ll also need to consider the roof pitch. The higher the pitch, the more shingles you will need to cover the whole roof.

Here is how to calculate the pitch of a roof.

  1. Assess the roof and estimate if the pitch is high, medium, or low.
  2. Carry a two-food level and climb the roof to the peak.
  3. Hold the level outward the peak and ensure the bubble is at the center of the indicator glass.
  4. Measure the distance between the midpoint of the level and the roof.
  5. Multiply the total roofing squares by the following digits.
  • High-Pitched Roof: 1.36
  • Medium Pitched Roof: 1.185
  • Low-Pitched Roof: 1.07

Step 4: Calculate the Amount of Shingle Bundles Your Roof Needs

A bundle of shingles is a package of roofing shingles, and the number of shingles in a bundle can vary, depending on the shingle size and brand. For instance, Brand X can have 26 shingles in a package while Brand Y 20. It could mean that the Brand X bundle covers more area.

So, it would help if you focused on the area that each bundle can cover. You can find this information on the wrapper of the shingle bundles. For instance, if the package is labeled “four bundles per square,” it will be easier to calculate the number of bundles.

Here is an example:

Suppose a gable roof has an area of 2,000 square foot gable, and you are investing in shingles with packages labeled as “four bundles per square.” You will need 80 bundles of shingles (20 squares x 4 bundles per square = 80 bundles).

Final Words

Now that you know the number of shingle bundles required on the roof, you realize that there are other roofing requirements to consider. While the shingle measurements are always in “square feet,” many roofing accessory products are measured in “linear feet.”

A professional roofing contractor will take note of additional roof dimensions and factor them into the calculations. They include the total lengths of valleys, eaves, ridges, and hips. That helps them determine the supplemental roofing materials for the entire work.

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