A Metal Roof Must Have Linear Feet
1 foot is the same as 2 feet if 24 inches and 12 inches are divided by 12 inches, a further 6 foot will be formed if 36 inches are divided by 12 inches. It would be a good idea to calculate the volume twice. 266 squares are multiplied by 533 square feet. The distance in linear feet is five thousand five hundred ninetyeight degrees. In order to produce 177, you need to repeat this process with the 3foot material. It measures 66 linear feet in length.
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.
Squares Rectangles And Triangles
Nearly every roof, no matter how simple or complicated, can be broken down into squares, rectangles or triangles. You can draw lines on your diagram from the ridge to the eaves to make triangles out of the hips. This will leave you with four triangles for the hips, two rectangles for the rest of the hip roof, and another rectangle for the leanto roof.
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Two: Split Tricky Shapes Into Squares And Rectangles
Once you have these figures, return to the safety of your home. Notice in the image above, the hip roof is made of two triangles and two trapezoids. Trapezoids are tricky to get the area measurement of, so were going to split each of them into two triangles and a rectangle:
We know enough about the overall measurements of the roof to fill in the missing values. Lets fill the figures in now:
How To Calculate Your Roof Area
Knowing how to calculate your roof area can be a beneficial first step in estimating the cost of a new metal roof. In roofing we call the calculation of roofing materials needed a takeoff.
A good roofing contractor will take the time make sure that the takeoff is accurate. Proper measurements and attention to roof details ensure that material shortages are avoided and prevent overages .
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So What Is A Roofing Square
A roofing square is a measurement, but it has nothing to do with square feet, meters, yards, or miles. A roofing square is commonly used by roofing companies and is roughly equivalent to 100 square feet. This measurement does not change whether it is a square of shingles or a square of tarp. This is because roofing squares are used to make calculating the cost of materials and labor easier than if you had to use square feet or yards.
Estimating Materials Based On Actual Measurements
Measuring each roof plane requires you to actually go onto your roof. If your roof has a number of planes and numerous hips, ridges and valleys, this is the most accurate way to calculate the materials needed. Take a metal tape measure and a pen and paper. Measure each planes length and width. Record your measurements. Once you are safely on the ground, use your measurements to determine the square footage.
For rectangular areas, multiply the length by the width. For example, if a plane measures 30 feet by 100 feet, this would be 3,000 square feet. For triangular areas, you may need to dust off your geometry book. If the area forms a right triangle, you can make use of the Pythagorean theorem. Otherwise, you might want to look up how to calculate the semiperimeter and then use Herons formula to find the area. Be sure to add extra for valleys, hips and ridges.
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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 upandover, 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.
How To Measure Your Roofs 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 homes square footage.
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Figuring Out The Square Footage Of Your Roof
While it may seem difficult at first, you can divide your roof into 10 x 10 roofing squares, a standard unit of measurement used by roofers.
But first, some terminology you’ll need to know:
 Ridge – Where two sloped roof areas meet
 Valley – Where two sloped roof areas meet , often with a metal channel running along the fold
 Hip Roof – Type of roof where all sides slope downwards to the walls
 Hip End – The triangle shaped end of a hip roof
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Straight To The Answer
Divide your roof pitch by 12. Roof pitch is given as the number of inches in height change over the distance of one foot. Dividing by 12 gives the ratio of inches in rise per distance. For example, a standard roof pitch is likely to be about 4. So for a pitch angle of 4, divide by 12 and get 1/3.
Square the result of Step 1. So keeping with our roof pitch of 4 this gives us 1/9.
Add 1, then take the square root. Adding 1 gives us 1 + 1/9 = 10/9, then taking the square root gives us about 1.0541.
Multiply by the square footage of a single floor of your house. So continuing our example, if you’ve got a two story house with a total square footage of 2,700 square feet, with each floor having 1,350 square feet, multiply 1,350 by 1.0541 to get 1,423 square feet. So you’d need 1,423 square feet of roofing.
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Square footage of your house

Pitch of your roof
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Calculate Roof Pitch From The Ground In Three Quick Steps
Roof pitch is one of those things that middle school math and geometry instructors can easily point to, and say, See? Learning how to work with rise over run is fun and useful, right? If at any moment you start having PTSD flashbacks to algebra or geometry class, take a deep breath. Well walk you through this slowly in three simple steps. All you need is a tape measure, and possibly a helper to hold it.
Step One: Grab that tape measure, notepad, and pencil and head outside. Find the slope of your roof youd like to measure, and start measuring the distance from the outer edge of the eave to the point at which the plane of the roof slope is barely visible to your eye. Write that number down in both inches. This figure is the horizontal run.
Step Two: Stand directly underneath the gutter or edge of the roof plane you want to calculate the slope for. Measure the distance from your eye to the top of the drip edge of your roof overhang. Write that number down in inches, too. This figure is the roof rise.
Step Three: Take the roof rise figure in Step Two and divide it by the horizontal run from Step One. In the example above, the rise is 60 inches and the run is 120 inches. This reduces down to a roof pitch of 6/12. Well use this figure in just a bit, so keep it handy.
How Many Rolls Of Felt Will You Need
Roofing felt is sold by the roll. The average roll of 15pound roofing felt covers about 400 ft2, or 4 squares, while the average roll of 30pound roofing felt covers about 200 ft2, or 2 squares.
Rolls of felt are 36 wide x 144 long for 15# and 72 long for 30#. Consider other underlayment options as needed, such as rubber or tar products.
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How Do You Figure Out How Much Underlayment To Use On A Roof
Divide the total footage by 100 to find the number of squares in the roof. Determine the number of rolls of underlayment needed. The #15 type is most commonly used, and one roll of #15 underlayment covers 4 squares. If youre using #15 underlayment and your roof slope is greater than 4:12, use 1 layer.
How Do I Calculate My Roofs Square Footage
The number of roofing squares that your roof is will have a significant impact on the amount you pay for materials and labor. Before you get an estimate from a trusted roofing expert, you may be interested in getting a rough calculation of the cost per square on your own. We have three easy steps that any homeowner can do that will help you calculate your roofs square footage.
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Figure Out Your Homes Footprint
If you use the square footage of your home, youll only get a vague idea of what the square footage of your roof is. Thats why you have to figure out your homes footprint.
A person of average height will have a stride somewhere between 2 to 2.5 feet. To figure out your homes footprint, you can step off 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, youll multiply the two numbers to get your homes 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 homes footprint. Keep in mind, square footage of a house does not equal the square footage of a roof.
Calculate The Roof Area
Now that you have all of your roof measurements, you can calculate its surface area. Simply multiply the length and width of each rectangular plane, and then add the combined area of the hips. Then multiply this number by the roofs slope factor, and then multiply this final result by 1.10 to allow for error.
In this example, our imaginary home’s hip roof would cover a surface area of + , while the leanto roof would be equal to . This gives you a total surface area of 935 square feet. Multiplying this by the slope factor of 1.03 equals 963.05 square feet. Multiply this by 1.10 to obtain 1059.4, which is a good estimate of your roofs surface area.
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How Many Nails Will You Need
Nails will also be required for any roofing project. The average 3tab shingle needs four nails per shingle. High wind areas and other types of shingles may need more. 320 nails will be needed to install a square of standard 3tab shingles, assuming four nails per shingle and 80 shingles per square.
Roofing Squares: A Way To Measure Your Roof
So youve decided to reshingle your roof, youve called the contractor and all seems well until the contractor comes down and you hear a term youre not familiar with, roofing square
What? you ask yourself, wondering what exactly the person you hired just said to you, did they mean a square foot, a panel, something else entirely? Dont worry, youre not alone. Its a question we at Rennison Roofing get all the time!
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How Do You Calculate Square Footage For A Roof
Related Articles
When a roof needs to be replaced, one of the first steps you may perform is figuring out the roof area. Both the roof area and pitch contribute to the cost of a roofing job. Calculate square footage for a roof by measuring and by performing some basic math equations. With the area measurement, you can learn the approximate cost of a new roof. Use this information if you are purchasing a home that needs a new roof or if your current home needs one.
Measure the ground dimensions of the house using a tape measure, and write down these dimensions. Multiply the length by the width to arrive at the ground area of the house. If the house has an irregular shape, measure each part separately, figure the separate areas and add them together.
Convert the area to roofing squares. Because each 100 square feet of roof is one roofing square, divide the total area from Step 1 by 100. The answer is the number of roofing squares for the roof.
Estimate the pitch of the roof. Roofs have one of three pitches: low, medium or high. A low pitch rises 3 inches every 12 inches of base horizontal length. A medium pitch rises 6 to 9 inches every 12 inches of base horizontal length. A high pitch roof rises more than 9 inches for every 12 inches of base horizontal length. Estimate the roof pitch by sight or calculate it with a level in the next step.
Things You Will Need
Why Is Roofing So Expensive
Tile and Asphalt are the most used materials for roofing, and theyre manufactured with the usage of concrete, clay or oil. The rise of oil prices can directly impacted asphalt shingles to become more costly. Furthermore, the cost of disposing old and damaged materials has also increased in the recent years.
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How Do You Calculate The Base Width Of A Roof
Our roof calculator uses base length and base width to find the estimated area. The base width is the distance from one corner of your roof to the other, at its base, on the short side of your house. The base length is simply the distance from the second corner to the third corner, on the houses long side.
How To Calculate A Roofing Square
Before beginning, make sure you can safely access your roofif you can’t, contact a roofing professional for help.
Grab your measuring tape, level, pen and paper, roof safety equipment, and your ladder. With these in hand, you can measure your roof in five simple steps.
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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.
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
 Payroll and payroll taxes
 Taxes
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.
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