## Why Is It Important

A roofing square is an important measurement for roofers. It is the most common way to measure a roofs size. Roofers use this measurement to calculate the amount of material they will need to cover a roof. This measurement is also used to price a new roof. A roofing square is equal to 100 square feet.

Roofers will measure the length and width of a roof and divide it by 100. This will give them the roofs square footage. Most roofs are not perfect squares, therefore this measurement may be difficult to calculate without a roofing square ruler or tool such as a credit card that is 100-square inches long.

## How Big Is A Square Of Shingles

If you are just starting out in roofing and construction, or youre undertaking a DIY roofing project on your home, then youll need to get to grips with the jargon and specialist units of measurement used in this industry.

One term you may have come across already is the common measurement of squares. This is a widely used term to describe how big a roof is and calculate how many shingles you will need to cover the roof. A roofer might refer to this as a roofing square, a square of shingles, or simply a square. Here, we explain the basics of roofing squares, why they are used, and how to calculate a square.

In This Article

## Whats Your Roof Slope

You will also need to know the slope of your deck.

To determine this, measure the vertical rise of your deck in inches over a 12 horizontal distance.

If this rise is 4, then your roof slope is 4 in 12.

Roof slopes are always expressed with the vertical rise mentioned first and the horizontal run mentioned second.

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## 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 of your home by.**

For example:

**For an easy up-and-over, walkable gable roof, youll 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.**

## Why Should I Measure My Own Roof

If you plan on re-roofing your own home then you will need to calculate materials so you wont waste your own time and money. If youre like most people, youll need to hire a professional.

Knowing your numbers will help you figure out what roofing materials are within your budget and having your square footage handy is a great way to protect yourself from inflated quotes.

**Recommended Reading: Roof Overhang Extension **

## S To Measuring Roof Square Footage

## Once You Have Your Roofs Pitch Divide The Number By 12

**How to measure a roof square**. Multiply this number by your most recent result to get the estimated square footage of your roof. Wear shoes with proper traction to avoid slipping. It is often compared to slope, but is not exactly the same.

Once you have your roofs pitch, divide the number by 12. Knowing your square footage and the 3 other cost factors lays the groundwork for learning the size of your roof investment. The square footage is found by multiplying the number of squares by the roof pitch.

If you ever came across the term roofing square and wondered whether it means squared feet or square yards, we hope this article cleared all your doubts. In our example, the roof pitch was 6/12. In order to determine the amount of shingles you need for your roof, youll need to know the square footage of your roofs surface.

To find how many squares are on your roof, divide the total square footage of all your planes by 100. So if you divide your answer of a product of length times. Need roof measurements to compare to a contractor’s or for yourself to.

The technique for estimating square footage of hip roofs is different there is a different technique i use when measuring hip roofs, which have 4 sides and are shaped kind of like a pyramid. 1 roof square = 100 square feet Use a tape measure to note the length and width of your roof, including dormers.

How to measure your total roof area. (for example, if your roofs pitch is 4 in 12, you would divide 4 by 12.

**Recommended Reading: New Roof Cost California **

## Builder Mike Guertin Explains 3 Ways To Calculate The Quantity Of Shingles You’ll Need For Your Next Roofing Job

One of the biggest challenges for experienced builder and novices alike is accurately estimating materials for a construction projectespecially for roofs, because they can be **difficult to access** for taking measurements.

But dont fretIn this excerpt from my book **Roofing with Asphalt Shingles**, I describe three reliable methods for determining the area of a roof, plus Ive included tips for estimating the number of extra shingles youll need for waste, overlaps, and starter shingles.

**Note:** be sure to take your time and double-check your numbers when calculating the quantity of shingles, underlayment, flashings, and other materials needed for your**roofing project**. The more accurate your estimates, the less time youll waste waiting for material deliveries during the project.

## S To Calculate Your Roofs Square Footage

You just learned what a roofing square is. The number of roof squares has a huge impact on the cost factors, such as the amount of materials used, labor, and time.

Before investing in a new roof, wouldnt it be great to know how much itll cost per square?

**If you answered yes, we have a great way to roughly calculate your roofs square footage to give you an idea of the cost of your new roof.** 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.

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## How Shingle Quantities Are Measured

Roof shingles are sold by both the bundle and by the square. A square of shingles is the quantity needed to cover 100 sq. ft. of roof. Shingles are packaged in paper- or plastic-wrapped bundles designed to be light enough for a person to carry, so heavier shingles require more bundles per square. Three bundles to a square is most common, which applies to most **three-tab strip shingles** and some lightweight laminated shingles. Heavier three-tabbed shingles and laminated shingles require four, or sometimes five, bundles to cover a square. When shingles come three bundles to the square, there are 29 standard-sized shingles in each bundle.

Figuring out the roof area is the first step to determine how many bundles youll need to order. There are two ways to size up a new or freshly stripped roof: the measurement method and the sheet-count method. Theres a third method for calculating bundles when youll be laying new shingles over old or if the old roof is still in place.

Once you have a bundle or square count for the main roof area, youll add additional shingles to account for waste, starter shingles, and extra shingles for hip and ridge caps.

## How To Measure A Roof

Getting accurate roof measurements can be difficult but with this roofing calculator, youll be well prepared to take measurements of any roof. Whether youre a contractor looking to train a new employee or a homeowner looking to do some renovations, youll find this guide helpful for any roofing project. Use the step-by-step guide below to accurately measure your roof and estimate roofing costs.

#### Step 1: How to Calculate Your Roof Square Footage

First, measure the length and width of each surface on the roof, then multiply these values to get the square footage of that surface. Make sure to document the number of chimneys, skylights or other obstructions and include dormers in your measurements. Youll also be recording the length of your house throughout this first step in order to calculate your total area.

Add up the square footage for each surface to get the total square footage of your roof. For example:

#### Step 2: How to Determine Your Roof Pitch

The next step is to measure the pitch of the roof deck. Youll need to figure out the vertical distance over a 12 horizontal segment . Record these values as roof rise over run, with the vertical measurement listed first and the horizontal second.

Its important to keep in mind that the roof pitch will be dramatically different for homes with a flat roof than homes with a steep roof.

#### Step 3: Calculating Roof Squares

#### HOVER Roofing Calculator

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## Roofing Pitch For Square Roof Area

Finally, the more complex part, measuring your roofs pitch.

*.*

Low Pitch: 1.07 x Roofing SquaresMedium Pitch: 1.185 x Roofing SquaresHigh Pitch: 1.36 x Roofing Squares

**NOTE:**We understand a roofs pitch makes this process somewhat tricky. Enjoy Home Advisors free roofing square calculator right here.

## What About The Waste Factor Should I Order Extra Roofing Materials

You want to order extra material to account for waste. Waste factors vary.

10%-15% is a good rule of thumb, but your results may be different. More complicated roofs will have a higher waste factor because there are usually more cut shingles around corners, walls, and edges.

It is okay to have a few shingles left over. They can be saved in case there is roof damage later or if repairs need to be done in the future.

So for the 24 square roof example, you would want to add 2.4 squares which equal about 7 or 8 more bundles.

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## How Much Roofing Underlayment

Up till now, we were discussing **how to measure roofing shingles** for re-roofing. When talking about a new roof, the same amount of square footage is required for the underlayment.

You will find underlayment in rolls of four squares each. In order to determine how many rolls of underlayment you would need, you need to divide the number of squares for 2 planes by rolls of one square.

**Rolls of underlayment required: 280 sq. ÷ 4 = 70 rolls**

If you are applying the shingles over an asphalt roof, then you dont need underlayment.

Pro Tip: In order to avoid any delays in installment due to shortage of shingles, add 10% to the total material requirement for trim allowance.

## How To Estimate The Size Of A Roof

If youre replacing a roof, the first consideration needs to be the roofs size so you can accurately estimate project materials.

In the U.S., roofs are measured in square footage, and roofing contractors typically quote projects based on the size of the roof in squares. Consequently, gathering the size of the roof in squares and square footage is the first step.

**Get Free Project Estimates**

Find Qualified Roofing Professionals in Your Area

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## Calculate The Complex Roof Areas

Most roofs in Canada would be considered on the complex side. Multiple adjacent pitches, dormers, and turrets are common. Keep in mind that an experienced metal roofing contractor will need to factor in extended labour time for areas of your roof that will require precision metalworking skills.

Start by finding the footprint area and multiply by the correct slope factor determined by pitch . In **Figure 4** below, the dashed blue lines give a simplified view of the footprint. Multiply L x W to calculate the area for each rectangular section. Note the area of 77ft2 that needs to be subtracted for the recessed area.

Once the footprint including overhang areas have been determined for each area, find the appropriate slope or pitch factor in the chart below. For example, a roof area with an 8/12 pitch has a slope factor of 1.202 so 2053ft2 x 1.202 = 2468ft2 total roof area.

*A Note about complex roofs: *Complex roofs need more accessories and trims thaneasy roofs resulting in a slightly higher total cost/square foot.

Figure 4. Calculating Complex Roof Area

## How Many Nails Required

After you are done calculating the total square footage, you need to determine the number of nails you will need.

**Usually 4 nails are used per shingle**. As mentioned earlier, shingles come in three tabs, which means you would need around **1,120 nails/sq.**

If you live in a high windy area, then you will need **6 nails per shingle**, which brings the count to **1,680 nails/sq.**

This calculation is based on **280 shingle squares**, according to the gable roof measurement. For the right nailing pattern, refer to the instructions that comes with the shingles.

And this is how you measure your roof area and the number of shingles and nails needed. If you are looking for more informatory articles such as this, then visit Epic Home Ideas.

**Recommended Reading: How Often Does The Roof Need To Be Replaced **

## Calculating The Area Of A Complex Roof

Areas of complex roofs with multiple hips and valleys take the most time to calculate. Start by making a rough sketch of the roof. To simplify the calculation, break down the sketch into rectangles and right triangles , then take as many measurements of the roof as you can to match the sides of the rectangles and triangles on the sketch.

Use visual cues from the existing roof shingles or roof sheathing to determine square lines off eaves edges or ridges. These cues will help you measure the lengths of the sides of the rectangles and triangles. For instance, the cutout slots on shingled roofs run perpendicular to the eaves, and nail rows in sheathing are pretty close to square also. It is difficult sometimes to get accurate measurements. Dont get too concerned though just round lengths to the nearest 6 in.

With the sketch filled in with measurements, you can determine the size of the roof area. The area of a rectangle is length multiplied by width, whereas the area of a right triangle is the length of the two sides that meet at the 90-degree corner multiplied together and divided by two .

Tally the square footages of all the rectangles and triangles, which will give you the total square footage for the roof. The example here shows the calculation for a roof with two hips.

## How Do You Calculate The Square Footage Of Your Roof

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

If so, youre 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. Thats why were going to break down how to measure your roofs 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.

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## Finding The Size Of The Roof In Squares

Roofing contractors estimate projects and materials by the square, so it is crucial to find this measurement to estimate the amount of material needed accurately. A square simply refers to a 10 x 10 square of roofing. This is simply 100 square feet of roof.

To find the squares, divide the overall roof area by 100 and then round up. For instance, if the roof is 1550 square feet, then it is 16 squares.

## What If You Have A Steep Roof

To measure a steep roof, use one of the following alternate methods:

#### Method 1

Calculate the roof length by measuring the exterior walls plus the overhang for the length of the house parallel to the ridge.

Next, throw a rope over the ridge and mark it where it meets each eave. This will give the width dimension to use in figuring your area. This should be done on each roof section containing a horizontal ridge.

#### Method 2

Determine the roof area by using a mathematical formula that accounts for the** roof length, total span, and roof pitch**:

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