How Will You Measure The Area Of A Triangular Roof?

How Will You Measure The Area Of A Triangular Roof
Download Article A simple guide to taking roof measurements and how to transfer them to a diagram Download Article Measuring your roof is the first step in a successful re-roofing project. You can actually get an estimate of your roof’s measurements from the ground if you’d rather not climb a ladder and get up on the roof yourself. Otherwise, you can climb up onto your roof to take more accurate measurements.

  • Measure the length, width, and pitch from the ground with a tape measure. Use a pitch multiplier and calculator to figure out square footage.
  • Get up on the roof to take and record precise measurements.
  • Draw the diagram using the precise measurements and break the diagram into smaller sections.
  1. 1 Find the length and width of the building’s exterior walls. Stretch your tape measure along the walls from end to end in both directions. Record these measurements in your notebook. Along with the roof’s pitch, you’ll use these 2 dimensions to calculate the roof’s overall square footage.
    • Once you’ve measured the building’s walls, estimate the length of the overhangs on either side (if your roof has them). The easiest way to do this is to simply eyeball them and approximate how long each one is in feet. Add these figures to your recorded measurements to account for the additional area.
    • Estimating the area from ground level is less precise than measuring each side individually, but it can make a quick, easy, and safe alternative when redoing a square or rectangular roof. To measure an irregularly-shaped roof, you’ll need to get on top.
  2. 2 Calculate the pitch of the roof. The pitch is the steepness of the roof. To find the pitch of your roof, you’ll first need to set up a ladder tall enough to reach it. Place a level against the rooftop a few feet in from the edge and angle it so that the floating bubble is centered, then measure the distance from the end of the level to the surface of the roof.
    • Pitch is expressed as “X-in-12 (inches)”. If you’re using a 1 ft (0.30 m) level, the pitch is the distance between the edge of the level and the roof’s surface. A distance of 7 inches (18 cm), for example, would mean your roof has a pitch of 7-in-12.
    • If you’re using a 2 ft (0.61 m) level, divide the distance between the level and the roof by 2 to get the true pitch. A 14 in (36 cm) difference, for example, indicates a pitch of 7 in (18 cm).
    • The terms “pitch” and “slope” are sometimes used interchangeably when describing roofing projects.


  3. 3 Use a pitch multiplier table to determine what figure to use. Pitch multiplier tables make it easy to use a particular pitch to estimate a roof’s square footage. Run a search for “pitch multiplier table” and look for the measurement of your roof’s pitch in inches on the left side of the table. Write down the corresponding pitch multiplier for use in your following calculations.
    • For example, a roof with a rise of 3-in-12 will have a pitch multiplier of 1.031, while one with a rise of 8 in 12 will use a multiplier of 1.202.
    • You should be able to pull up a number of reliable pitch multiplier tables with a quick Internet search.
  4. 4 Multiply the area by the pitch multiplier to get the roof’s square footage. First, multiply the length by the width. Then, take the product of these two dimensions and multiply it by your pitch multiplier. The number you get will be an accurate estimate of how much area you have to cover for your roofing project.
    • If your roof measures 48 feet (15 m) x 24 feet (7.3 m), multiplying its length by its width would give you a square footage of 1,152 square feet (107.0 m 2 ). If its pitch is 6-in-12 (a pitch multiplier of 1.12), multiplying 1,152 sq ft (107.0 m 2 ) by 1.12 would give you an overall square footage of 1,290 square feet (120 m 2 ).
  5. 5 Divide your estimated square footage by 100 to estimate your materials. Roofing materials are bundled in “squares” that contain enough shingles to cover 100 square feet (9.3 m 2 ). Dividing 1,290 sq ft (120 m 2 ) by 100, for example, will tell you that you need to order at least 13 squares to get the job done.
    • Always order 10% more materials than you think you need to account for waste, and round up to make sure you don’t come up short. In the above example, you’d need 15 squares.
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  1. 1 Find a safe way onto the roof. In order to be able to take precise measurements of your roof, you’ll need to actually be on it. If you have an interior window that provides roof access, use it to step out onto a secure section. Otherwise, it will be necessary to set up an extension ladder and climb onto the roof carefully.
    • Bring a tape measure, pen or pencil, and notebook or pad of paper with you. You’ll need these items to record your roof’s measurements.
    • Make sure your ladder is resting on a flat, stable patch of ground. If possible, have a helper hold it for you to stabilize it as you climb.
  2. 2 Measure each side of the main section of the roof. Extend your tape measure along the outer edges of the roof to find its length and width in feet. For square or rectangular roofs, you’ll only need to record the length and width. For sloped sectional roofs, write down the dimensions of each individual plane.
    • Complete one side at a time before moving on to other areas. You’re just looking for the outer perimeter at this stage.
    • In this context, a “plane” is defined as each flat, continuous section of the roof.
  3. 3 Measure any additional structures separately. If your roof features any architectural elements like hip ridges, valleys, or dormers, don’t forget to find the length and width of these areas, as well. These measurements will factor into your calculations and, therefore, the amount of materials you’ll need to buy.
    • Ridges and valleys are the top and bottom contours where smaller hip sections join the main part of the roof.
    • Dormers are separate protruding structures that house windows in the upper floors of the house. They’re ordinarily roofed separately.
    • There’s no need to account for chimneys, pipes, or other irregularities. You or your roofing contractor will work around these areas once the project is actually underway.
  4. 4 Record your measurements precisely. As you take your measurements, jot them down in your notebook or on a separate sheet of paper. You’ll be using these numbers to calculate the total square footage of the roof later on. Write out each measurement exactly as it appeared on your tape measure to the nearest 1 ⁄ 2 inch (1.3 cm).
    • Don’t round your roof measurements up or down. This will be done once it’s time to determine the number of shingles you need. Rounding before you begin multiplying and adding may throw off the accuracy of your final estimate.
  5. 5 Draw a diagram of your roof on a large piece of paper. Make a rough top-down sketch of your roof. Pencil in the outlying shape, then flesh out your diagram with details like ridge lines, hips, valleys, and dormers until you have a rough representation of your roof’s basic layout.
    • Your diagram doesn’t need to be perfect. All that matters is that you have a visual aid to keep up with the various dimensions you’ll be using to make your final calculations.
    • Use a pencil rather than a pen. That way, you’ll be able to make corrections and revisions as needed while you work.
  6. 6 Use the measurements you took to label your diagram. Write down the length and width of each corresponding section of the roof, starting with the outer edges where the eaves are. Then, put down the length of the ridge lines on each peak, hip, and valley.
    • The idea is to reduce your roof to a series of lines in order to simplify your subsequent calculations.
  7. 7 Divide the roof up into simple geometrical sections. At this point, you may notice that many of your roof’s planes are irregular. The easiest way to get around this problem is to draw a few extra lines to turn complex shapes into simple ones. For example, drawing a line across the tapered end of a gabled roof will create a long rectangle connected to a small triangle.
    • Keep lining off the different parts of your roof until each section is a square, rectangle, or triangle.
    • Breaking your diagram up into smaller sections may seem unnecessarily complicated, but it will actually make your final calculations much faster and easier (unless you want to figure out how to find the area of a trapezoid).
  8. 8 Multiply the length by the width to find the area of rectangular sections. Determining the square footage of these sections is easy. Just multiply the length and width dimensions. Make a note of the square footage of each square or rectangular section on your diagram.
    • If a section is 120 feet (37 m) x 100 feet (30 m), its total square footage would be 12,000 square feet (1,100 m 2 ).
    • Be sure to find the area of any dormers on your roof, as well.
  9. 9 Work out the area of the remaining triangular sections. This isn’t as difficult as you might think. First, use a ruler to draw a line from the center of the longest side of the triangle (the eave) to the point (the roof’s peak). Then, multiply the length of the longest side by the length of this central line. Divide this number by 2 to get the square footage of the triangle.
    • The basic formula for finding the area of a triangle is ½ the base times the height (in this case, the distance between the base and the peak). If you have a roof section that’s 30 feet (9.1 m) long and 12 feet (3.7 m) high, multiplying those dimensions would give you an area of 180 square feet (17 m 2 ).
    • Measure and mark the square footage of each triangular section carefully, as these tend to differ in size.
  10. 10 Add up the areas of each section to get your total square footage. Punch each of the area measurements you deduced into a calculator one by one. The sum of these numbers is the overall square footage of your roof, which you can then use to work out how much material you’ll need for your project.
    • Together, two 750 sq ft (70 m 2 ) rectangular planes and four 135 sq ft (12.5 m 2 ) triangular planes would give you a total area of 2,040 square feet (190 m 2 ).
    • Add up the numbers a few times to ensure that the final figure you get is correct.
    • Take your time and work carefully to prevent mistakes. Even a small miscalculation could end up costing you time or money.
  11. 11 Divide your square footage by 100 to estimate your materials. Roofing materials are typically packaged in “squares,” each of which is the equivalent of 100 square feet (9.3 m 2 ) of roof space. Dividing the total area of your roof by 100 will therefore help you figure out how many squares worth of shingles to order,
    • For a 12,000 sq ft (1,100 m 2 ) roof, you’ll need a minimum of 120 squares.
    • It’s a good idea to add an extra 10% to your estimated material requirements to account for waste and ensure that you have enough shingles to cover your roof when it’s all said and done. Using the above example, that would be 132 squares.
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  • Question Can you measure a roof from the ground? David Bitan Roofing Contractor & Maintenance Professional 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. Roofing Contractor & Maintenance Professional Expert Answer Support wikiHow by unlocking this expert answer. One easy way is to use a roof measurement website that utilizes satellite imagery. This way, you don’t have to climb on your roof at all. However, if you feel you can safely go up on your roof, measure each section starting at the top of the ridge and going down to the bottom of the slope. The combination of these sections will give your the square footage of your roof.
  • Question How do you calculate the area of a rectangle? David Bitan Roofing Contractor & Maintenance Professional 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. Roofing Contractor & Maintenance Professional Expert Answer

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  • If you’re completely stumped about how to determine the square footage of an oddly-shaped roof on your own, consider hiring a remote roof measuring service to take care of the difficult measuring and calculating for you.
  • As the old handyman’s adage says, always measure twice to ensure that you end up with accurate dimensions.
  • Pull up an online roofing calculator if you need help finding the area of irregularly-shaped roof sections (or you just want to double-check your work).

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Reshingling a roof is a complex and expensive project, one that’s usually best left to the professionals.


  • Ladder
  • Tape measure
  • Level
  • Straight edge or ruler
  • Notebook or pad of paper
  • Pencil or pen
  • Calculator
  • Tape measure
  • Notebook or pad of paper
  • Pencil or pen
  • Calculator
  • Online pitch multiplier table

Article Summary X To measure a roof, start by measuring the length and width of the building’s exterior walls and multiplying them to get the area. Then, calculate the pitch of the roof by placing a level against it, angling the level so the bubble is centered, and measuring the distance between the end of the level and the roof.

How do you find the area of a triangle roof?

Triangles. Recall that the formula for the area of a triangle is A = 1 2 b h, where is the length of the base, and is the height of the triangle. Remember, that the height of a triangle is also called the altitude, and goes from the vertex at the top of the triangle to the base and is perpendicular.

How do you measure the area of a roof?

To calculate your roof area, simply multiply your roof length by your roof slope height, and multiply this by two. This should give you the total area of your roof, not accounting for a chimney or other sections of your roof not covered by tiles.

What is the triangular roof?

Gable – This is one of the most often used roof shapes. It’s likely you have at least one of these on your home, shed or garage. The gable refers to the classic triangular wall shape where 2 sloping roof sides meet at a peak. The two sides of the roof are connected along the top ridge and each slope downward. The end walls will look like a triangle.

How do you use a triangle roof?

Construction – Unlike the Stone Triangle Ceiling, the Stone Triangle Roof is slightly inclined. Once the first Stone Triangle Roof is placed, subsequent Stone Triangle Roofs can snap into place along the first one, allowing them to line up, provided that there is adequate room to do so. A roof requires support from a nearby foundation or pillar in order to be placed.

Why is the roof a triangular shape?

Protection against enviromental hazards – Pitched roofs are built to withstand snow, ice, water and wind. Shaped as a triangle, they are stable, stronger and ensure perfect water drainage. Some roofing tiles, like natural slate, are extremely tough, waterproof and fire-resistant.

What tool is used to measure a triangle?

A protractor is one of the most common tools to measure angles.

How much is the measure of a triangle?

The sum of the three angles of any triangle is equal to 180 degrees.

What are the triangle roof supports called?

What is a Roof Truss? – You might be wondering, “What is a trussed roof?” And you also may be wondering how trusses differ from rafters. A roof truss is best described as a structural framework of timbers that’s designed to provide support for a roof.

They’re also used to bridge the space above a room. They typically occur at regular intervals, and they’re linked by horizontal beams known as purlins. One of the main differences between truss roofs vs. rafters is the fact that trusses are prefabricated wooden structures while rafters are usually built on-site.

For trusses, the triangular webbing of structural pieces not only provide support for the roof, but they also tie the outside walls of the home together. Find qualified roofers near you Another key difference between the two is that trusses mainly use 2x4s instead of wider dimensional boards.

  1. Since the materials aren’t as strong, more material ends up being used.
  2. Trusses have become increasingly popular over the past half-century.
  3. In the next sections, we’ll discuss the pros and cons to help you determine if they’re the right fit for your home.
  4. Once you know the advantages and disadvantages of each, you’ll have a better idea of which one would be right for you.

Let’s get started by reviewing the pros.

What is the triangular roof structure that supports the roofing?

King post – A king post is a central, vertical post used to provide support for the principal rafters and has struts that extend up and out from them. When you look at older buildings with exposed roof beams, the king post is in the centre of the triangular shape that forms the roof’s shape.

Which word means a triangle shaped end of a building roof?

Ga·​ble ˈgā-bəl. : the vertical triangular end of a building from cornice or eaves to ridge. : the similar end of a gambrel roof.

Why is triangular shape used in trusses?

Triangle – The triangle is a polygon, because all of its sides have straight lines. It has three corners and three sides the type of triangle I am talking about is equilateral. The angles of a triangle add up to one hundred and eighty degrees. It is one of the geometric shapes.

All triangles are two dimensional. It is studied in geometry. Geometry is the study of property and relationships of points, lines, angles surfaces and solids. Some important facts about triangles, they have three sides. They have three points, corners or angles. All three sides connect and are straight.

A triangle is a rigid strong shape because of its stability. The triangles make up the truss design. They are in an assembly of triangles made from a series of straight bars. The triangle is used because of its strength and stability. The truss is also identified by the shapes of the triangle in its design.

  • The extremely strong triangle is the only geometric form that can not be bent out of shape.
  • From as far back as ancient times the triangle has been held in high esteem.
  • For the Egyptian, they were very sacred in the form of the pyramids.
  • The pyramid has four triangles as sides and a square base.
  • A modern extension of the triangle and the pyramid is the geodesic dome which combines triangles and pyramids.

To get ready for this lesson I will read The Shape of Things. The first strategy is knowledge. The students will recognize a triangle and distinguish it from other shapes. This will be through identifying it among other shapes. While drawing some of the pictures, they will be able to use the triangle.

The comprehension will take place when comparing them to other shapes while doing a puzzle and completing a truss making exercise. The truss bridge will help with comprehending what this shape looks like. Application will be when the Popsicle triangles will be made. The students will be using triangles to make this type of bridge.

The analysis will come when the distinguishing of the shape will be done. This will also be evident through when they do the actual making of the triangles. The triangle has equal sides and that has to be understood. One of the characteristics that make it so unique is the equal sides.

  • They will create designs using triangles.
  • They will label their shape.
  • How the student will be using evaluation of the knowledge of a triangle is through choosing the correct form to make triangles.
  • To further explore the strength of a triangle you must remember that two dimensional shapes are flat.
  • I would hope to build a tetrahedron.

A regular tetrahedron is a three dimensional form created by four equilateral triangles with all edges connected. It is just a four sided triangle. Each will build one and take it home. Also a learning center will be set up to let the students’ build three dimensional objects from flat shapes.

What is triangular structure?

Geometry and architecture are two disciplines that are fundamentally linked. One of the most recognized geometric shapes is the triangle. Triangles are identified by the three angles that are linked through line segments to form a three-sided shape. The two most common triangular forms used in architecture are equilateral and isosceles.

What is the purpose of triangular?

Triangular function Not to be confused with or, Tent function, often used in signal processing triangular function A triangular function (also known as a triangle function, hat function, or tent function ) is a function whose graph takes the shape of a triangle.

Often this is an of height 1 and base 2 in which case it is referred to as the triangular function. Triangular functions are useful in and communication systems engineering as representations of idealized signals, and the triangular function specifically as an kernel function from which more realistic signals can be derived, for example in,

It also has applications in as a pulse shape for transmitting and as a for receiving the signals. It is also used to define the triangular window sometimes called the,

What is the shape of a roof called?

Roof shapes include flat (or shed ), gabled, hipped, arched, domed, and a wide variety of other configurations detailed below, Roof angles are an integral component of roof shape, and vary from almost flat to steeply pitched, Roof shapes differ greatly from region to region, depending on the climate, materials available, customs, and many other considerations,

How do you find the area of a triangle with all three sides?

Area of triangle = √, where s is the semi-perimeter of the triangle, and a, b, c are lengths of the three sides of the triangle.

What is a formula for a triangular prism?

Volume of Triangular Prism – The volume of a triangular prism is equal to the product of the triangular base area and the height of the prism. The formula to find the volume of triangular prism is given by:

Volume = Area of the Base × Height of prism


  • Since, the base is in triangular shape, therefore,
  • Area = ½ b h
  • Hence,
  • Volume of Triangular Prism = ½ × b × h × l

    Where b is the base length, h is the height of the triangle and l is the length between the triangular bases.

    What is the formula of heights of triangle?

    Altitudes of a Triangles Formulas

    Triangle Type Altitude Formula
    Equilateral Triangle h = (½) × √3 × s
    Isosceles Triangle h =√(a 2 −b 2 /4)
    Right Triangle h =√(xy)

    What is Heron’s formula for area of triangle?

    Heron’s formula, formula credited to Heron of Alexandria (c.62 ce) for finding the area of a triangle in terms of the lengths of its sides. In symbols, if a, b, and c are the lengths of the sides: Area = Square root of√s(s – a)(s – b)(s – c) where s is half the perimeter, or (a + b + c)/2.