Roofing is a complex industry filled with confusing terminology. One such term that often arises is the “square.” Understanding what a “square” means in roofing is crucial when evaluating roof replacement bids.

This article will delve deeper into two commonly used roofing terms: “square” and “bundle of shingles.”


What is a Square in Roofing?

When it comes to roofing, a “square” is a unit of measurement that refers to an area of 100 square feet. This measurement is crucial for roofers to help us accurately calculate the size of a roof. We can estimate the materials needed for the project by determining the number of squares.

Imagine you are planning to replace your roof and hire a roofing contractor. First, they will measure the roof’s dimensions to determine the number of squares. For instance, if your roof measures 1,500 square feet, it would be considered a 15-square roof (1,500 divided by 100). This information is vital for the contractor to provide you with an accurate estimate and ensure they have enough materials to complete the job.

Additionally, understanding the concept of squares can help homeowners make informed decisions when discussing their roofing needs with contractors. By knowing the size of their roof in squares, homeowners can better understand the cost of materials and labor involved in the project.

Defining a Bundle of Shingles

Another important term in roofing is the “bundle of shingles.” A bundle refers to a package that contains a specific quantity of shingles. The number of shingles in a bundle can vary depending on the type and brand used.

When purchasing shingles for your roof, it is crucial to consult the manufacturer’s specifications to determine the bundle count. Different manufacturers may have different bundle counts based on shingle size, weight, and packaging efficiency.

For example, let’s say you have chosen a brand of shingles that comes in bundles of 30. This means that each bundle contains 30 individual shingles. However, it is essential to note that not all shingles will cover the same area. Some shingles may be larger or smaller, resulting in variations in coverage per bundle.

By familiarizing yourself with these roofing terms, you can have more meaningful conversations with your roofer, make informed decisions, and ensure the success of your roofing project.

The Relationship Between Shingles and Squares

Calculating the Number of Bundles Per Square

Consider the shingle’s exposure to determine the number of bundles needed for a square.

You will need approximately three bundles per square for a standard three-tab asphalt shingle, which typically has a 5-inch exposure. On the other hand, architectural shingles, which have a larger dimensional appearance, typically require four bundles per square due to their larger size.

When it comes to calculating the number of bundles per square, it’s important to take into account the shingle’s exposure. The exposure refers to the portion of the shingle that is visible once installed. This measurement is crucial in determining how many shingles are needed to cover a specific area.

For example, a standard three-tab asphalt shingle usually has a 5-inch exposure. Each shingle will cover 5 inches of the roof’s surface. To calculate the number of bundles needed for a square, you would divide the total area of the roof by the area covered by a single shingle. You would need approximately three bundles per square for a three-tab shingle with a 5-inch exposure.

On the other hand, architectural shingles have a larger dimensional appearance than three-tab shingles. These shingles are designed to mimic the look of natural materials, such as wood or slate. Due to their larger size, architectural shingles typically require four bundles per square. Each shingle covers a larger area than a standard three-tab shingle.

Factors Influencing the Number of Bundles

Several factors can influence the number of bundles needed for a roof. These include the roof’s pitch, the design’s complexity, and the presence of dormers or skylights. Higher-pitched roofs, for example, can require additional shingles, thus increasing the number of bundles needed.

When calculating the number of bundles needed for a roof, it’s important to consider the pitch of the roof. The pitch refers to the steepness or slope of the roof. A higher-pitched roof will require more shingles compared to a roof with a lower pitch. This is because the steeper angle of the roof means that more shingles are needed to cover the same area.

In addition to the pitch, the complexity of the roof’s design can also impact the number of bundles needed. Roofs with multiple angles, valleys, or dormers may require additional shingles to ensure proper coverage and protection. The more intricate the design, the more shingles will be needed to account for the various angles and corners.

Furthermore, dormers or skylights can also affect the number of bundles needed. These features create additional areas that need to be covered with shingles, increasing the overall surface area of the roof. It’s important to carefully measure and calculate the shingles needed for these specific areas to ensure a proper and seamless installation.

Types of Roof Shingles and Their Bundle Count

Asphalt Shingles

Asphalt shingles are the most common type of roofing material. They come in various styles and colors and are known for their affordability and durability. Most asphalt shingles are sold in bundles containing approximately 26 to 42 shingles, depending on their size and weight.

Architectural Shingles

Architectural shingles, laminated or dimensional shingles, are a premium roofing option. They offer a more textured appearance and longer lifespan than traditional three-tab shingles. Bundles of architectural shingles typically contain around 20 to 22 shingles.

Importance of Accurate Shingle Calculation

Avoiding Material Waste

Calculating the correct number of shingles is crucial to avoid unnecessary material waste. Ordering excessive bundles can lead to unnecessary expenses and environmental impact. You can save money and reduce waste by accurately calculating the number of bundles needed.

Ensuring Adequate Coverage

On the other hand, failing to order enough shingles can result in inadequate coverage, leaving your roof vulnerable to leaks and other damage. By accurately estimating the required number of bundles, you can ensure proper shingle coverage and protect your investment in your home.

Common Mistakes in Shingle Calculation

Misunderstanding Roofing Measurements

One common mistake in shingle calculation is misunderstanding roofing measurements. It is important to accurately measure the dimensions of your roof’s surface area to calculate the number of squares needed. Failing to do so can lead to inaccurate estimations and potential delays in your roofing project.

Overlooking Shingle Overlap

Another common oversight is failing to account for shingle overlap. Overlapping is necessary to create a watertight seal on your roof. When calculating the number of bundles needed, it is crucial to consider the additional shingles required for proper overlap, especially at the eaves and ridges.


When estimating the number of bundles of shingles required for your roofing project, understanding the relationship between shingles and squares is vital. By familiarizing yourself with roofing terminology, considering factors that influence bundle count, and being aware of common mistakes, you can ensure accurate calculations and a successful roof installation.

Whether you’re looking for a high-quality roof installation, repair, or new gutters and siding, AIC is here to help. We believe in and practice the best customer service possible, including showing up on time, following through on what we say we’ll do, and treating people with common decency and respect.

Our in-home consultations are free, informative, and low-pressure. Please contact us by texting, calling, or filling out our contact form.

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