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How To Calculate Roofing Materials

Roofing Calculators Online: Truss System Area Pitch All Materials

How to Estimate Roofing Materials for Gable Roofs Construction Math

Every architect and professional construction company have a program to calculate a roof.

However, this program will be helpful for land owners, who decided to build their houses themselves and who need the roof calculator. Moreover, steadiness of the roof structure, its appearance and facade depend on accuracy of calculating.

Each roof calculator online tool at our website gives user an opportunity to calculate accurately the amount of materials required for construction of selected roof type, as well as to verify the correctness of calculated rafter roof system and other construction elements.

At the moment it’s possible to calculate pent roof, gable roof, mansard roof and hip roof, as well as rafters and wood trusses. The calculation of pavilion roof construction will be possible shortly.

How Do I Estimate The Cost Of A New Roof

To estimate the cost of installing a new roof, one of the first things you need to know is the size of the roof. The average roofing company uses the term squares when referring to the size of a roof. A square is a 100-square foot area.

Next, you need to multiply the number of squares by the cost of materials. Its crucial to have up-to-date information and price lists as prices can change at any given moment based on supply chain issues.

You also need to know the:

• Amount of time it will take to complete the job.
• Number of people needed on the job.
• Hourly wage of each employee.

Finally, you will have to add other costs like transportation and special equipment.

The information above is an overview of what you need to estimate the cost of a roof and create a roofing estimate template. Keep reading to learn how to calculate these costs and create an estimate that matches your customers price in the end.

Consider All The Roofing Materials Needed

Once you have the surface area of the roof, you multiply it by the roofing material costs. Many vendors of roofing materials sell them by the square, so this is a good measurement to use when ordering materials.

These are common materials used:

• Shingles the most common shingles come packaged as three bundles per square.
• Vents and flashing/boots for plumbing and other ventilation pipes.
• Nails like drywallers, roofers go through a lot of nails and/or screws. Shingle manufacturers generally recommend using 4-5 nails per shingle, depending on the row and how windy it is in your climate. This comes up to about 320-480 nails per square.
• Underlayment and ice and water shield underlayment packages usually tell you how many squares the package will cover. Ice and water shield is used on a roofs valleys and other vulnerable areas.
• Protective tarps much like painters, roofers tarp the lawn and items in the attic while they work. You also need to tarp the roof when it starts raining in the middle of a job, and other times you leave the jobsite before the roof is finished.

Regardless of the type of material, you want to add 10-15% to the amount you need, so you dont foot the bill for any supplies that become scrap.

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Now that you have an idea of what to expect, gathering and evaluating roofing estimates will be much less overwhelming. But even with this background knowledge, dont be shy about asking your roofing candidates any questions you haveno matter how nitty gritty. Roof repairs arent cheap, so clarify anything youre unsure of before you sign on that dotted line.

Eager to get your feet back on the ground? Check out our DIY section for projects you can safely handle yourself.

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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Measuring Or Calculating Gable And Hip Lengths

The slope factor is also used to determine gable lengths when the run length is known. For example, in Figure 4 the bottom left gable measures 16 across from eave to eave and therefore has a run of 8. When this is multiplied by 1.202 the gable distance is 98 . Note that this run can also be multiplied by the hip/valley factor of 1.563 to get a valley length of 126.

Record all your calculations on your drawing as seen in Figure 5 below.

Figure 5. Completed Roof Plan Drawing

Pro Tip: A Note About Waste Factor

Once you have figured out your roof area, you will need to also calculate how much room you need to allow for waste. For metal roofing products on a medium complex roof a waste factor of 15% is advisable. In other words for the 2468 ft2 roof in our example you should multiply by 1.15 giving you 2838.2 ft2 roofing material needed.

Important Note: Most metal roofing products are packaged and sold by the square so for our example roof the number of squares or boxes to purchase is 29.

Weight Of Roof Systems

Note that roof systems typically include more than one type of material.

A built-up roof, for example, will typically include the built-up membrane itself, with or without gravel, as well as some kind of insulation and cover board, which will vary in thickness from roof to roof.

When it comes to estimating the weight of roofing materials for an existing roof, field verification of the in-place construction is necessary in order to see what is actually on the roof. There may be more than one roof system in place.

Dont forget to add all roof assembly materials when calculating total roof weight. Depending on what you are using this information for, this can include the roof deck and the supporting structure as well as the roof system itself.

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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.

Measure The Base Area Of Your Property

How To Calculate Materials for Roofing

Now, use that tape measure again and take the distance from the edge of one of the eaves to the other edge along the same wall. Record that figure in feet. That will be the roof base width.

Then, measure the distance of the other side of the structure from the edge of the eave to the other. That will be the roof base length.

Multiply those figures together to get an estimate of the base area for the roof structure. For example, if your roof base width is 35 feet and your roof base length is 60 feet, the total base area would be 2,100 square feet.

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How Long Does A Roofing Estimate Take

A roofing estimate can take anywhere from 1 to 3 days. When you first meet a customer, you will likely:

• Discuss what needs to be done, the type of roofing material options, and the pros and cons of each.
• Ask the customer about the age of the roof and if theyve noticed any leaks.
• Agree on a timeline for the job.
• Inspect the roof to get its exact measurements, pitch, and locations of unusual roof features like solar panels, skylights, or satellite dishes.

When you have the specifics of a roofing job, you may need a day or two to source material prices, special equipment, and check the availability of your roofing team.

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 take-off.

A good roofing contractor will take the time make sure that the take-off is accurate. Proper measurements and attention to roof details ensure that material shortages are avoided and prevent overages .

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Now you need to find the costs of your other materials as well as labor and overhead. When you first learned how to bid a roofing job, its likely that you neglected several key costs, including a portion of rental costs or insurance costs. This list will help you find those missing costs.

First, before you start calculating your materials and labor, refamiliarize yourself with any relevant building codes, because they can significantly impact your calculations. For example, some municipalities require you to use more than four nails to secure shingles. Others require an ice and water protector. It all depends on the location of the home.

Once youre ready, calculate each material youll need:

• Nails: If youre using IKOs Cambridge® shingles, youll use approximately 240 nails per square, or 360 nails per square when installing by the High Wind Application Procedure. Our shingles are larger than many brands, and along with their larger exposure, theyll need fewer nails than most others, which is a great way to cut costs. If youre using another shingle with a smaller size and exposure, and consequently less coverage, youll likely need to use more nails. You can keep track of how many nail boxes you use on each unique job, which will help you come up with more exact estimates for your future bids.
• Vents: For some jobs, you can keep the vents as is, or reuse them, but not always.
• Determine How Many Barges You Need

Similar to the above, only with the slope length instead of the roof width, divide your length by the cover width of the barges:

Not only do you just rounded up this time, but you also double that figure to account for both the left- and right-hand sides of your roof. This means you would need 4 left hand barges and 4 right hand.

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What Do I Need In My Roofing Estimate Template

A roofing estimate template makes it faster and easier for you to give estimates to customers. By creating a document or spreadsheet with standard fields, all you have to do is enter the specific information of a job.

Your roofing estimate template should then calculate an accurate price for your roofing bid.

Besides costs, timelines, and a description of the work to be done, your roofing estimate template should include:

• An estimate number.
• Date of the estimate and an expiry date in case prices change.
• Payment information including details about deposits, the payment schedule, and accepted forms of payment.

Some roofers also provide a warranty to their customers. If your business does this, its best to include a roofing guarantee template in your estimates or invoices.

Now lets take a closer look at three of the major factors that affect the cost of installing a new roof and, therefore, are an essential part of a roofing estimate template.

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.

HOVER Roofing Calculator

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Roof Calculator Estimate Local Roofing Prices For 2021

\$4,200-6,600\$9,500 – 16,000Calculate your roof cost now:

Our calculator is based on the US roof market, and prices are calculated in USD. While Canadian market is very similar, due to currency fluctuations, you should also use the current exchange rate to get a more accurate number.Number of roofing projects estimated by RoofCalc.org since 2012:

How To Estimate Roofing Materials

Construction Master Plus EZ Roofing Materials Estimating How To

This article was co-authored by David Bitan. David Bitan is a roofing professional, licensed contractor, and the owner and founder of Bumble Roofing based in Southern California. With over 12 years of construction industry experience, David specializes in restoring, repairing, and maintaining residential, commercial, and industrial roofs. With over 60 years of combined experience, Bumble Roofing provides easy, friendly services to structures including residential, commercial, industrial, multi-family, and government buildings along with hospitals, hotels, and churches. This article has been viewed 697,513 times.

Knowing how to estimate roofing materials is important. Not only will it help eliminate waste, but it will also ensure that you buy just enough for the roofing job. Youll have to calculate your roof area, or the overall size of your roof, to determine the amount of materials youll need. This wikiHow will show you how to estimate roofing materials for your next project.

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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.

Final Thoughts On Measuring Your Roof

If youre looking for a simple ballpark estimate of your roofing materials needs, Google Earth really does a great job of quickly allowing you to measure the square footage youll need to cover. While its technology sure is surreal, it has drawbacks in its ability to precisely measure distances represented in 3D. Therefore, it can be helpful to gauge estimates of your materials costs by measuring from the ground and on top of your structure. As always, if youre feeling confused, dont hesitate to get in touch with a local roofing contractor to help you out. Many will provide estimates for free. Simply ask how many squares of material they estimate youll need, and compare that to the results you got from using any of the methods we outlined above.

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
• 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.

Table Of Roofing Material Weights

Note: The values in the table are for the installed weight of roofing materials. Shingles, tiles, and panels overlap the weights for these materials will be higher per square foot than for the uninstalled weights of the same materials.

Weight of Roofing Materials
These are the weights of typical actual products the weights of other actual products of the same type may vary.
Roofing Material

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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.

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