When homeowners need to repair their roofs, it is important to ensure that they obtain the right number of shingles to complete the project. No one wants to come up short once the work is already underway, but purchasing significantly more shingles than needed can be an expensive mistake.
Although square footage and shingle calculators may help, if the roof is measured incorrectly, the measurements that are input into these calculators could lead to inaccurate results.
Outlined below are seven steps for how to measure a roof for shingles accurately.
1. Draw A Diagram
Before heading onto the roof to take measurements, take some time to sketch an overhead view of the roof’s shape in a notepad so that each measurement can be jotted down on the right plane.
It is not necessary to draw this diagram to scale, but you should use distinct and clear two-dimensional shapes such as squares and rectangles to represent each plane of the roof.
2. Set Up For Taking Safe Measurements
Before heading up to the roof, ensure the ladder is set up on level ground. The base should extend at least three feet out from the roof’s edge to create a stable support. Be sure to enlist the help of another person to hold the ladder steady while standing on the ground. This person should also be responsible for contacting emergency services should an accident occur.
Before heading up to the roof, use fall arrest equipment such as shock absorption lanyards, braided rope lifelines or harnesses to prevent trips, falls and slips. Place your notepad, tape measure and pencil securely in your pocket while climbing the ladder and remember that you must always keep three points of contact while climbing. Closed-toe footwear featuring a solid grip can provide better traction while up on the roof.
3. Obtain The Measurements Of Each Plane
Head to the peak of the roof to confirm the sketch is correct and orient it to your current position so that each plane is labeled accurately. Begin with one section and lay the measuring tape out along the plane’s length, then write the measurement in the corresponding location in the sketch.
Then, place the tape along the width of the same plane and jot down that measurement. When measuring from the roof’s peak, plant your feet on one side of the roof and then feed the measuring tape downward to the roof’s bottom edge.
Then, measure from the edge to the peak. When measuring parallel to the peak, begin with the tape measure at the edge of the roof on one side of the peak and run it across the length of the peak to the other edge of the plane.
4. Do The Math
After safely descending the ladder while a partner holds it steady, use the measurements to calculate the square footage of each plane. If you have planes that are not square or rectangular, such as a trapezoid or triangle, you can look up the formula for calculating the surface area online.
After calculating the area of every plane on the roof, add it together to determine the roof’s total square footage.
5. Calculate The Roofing Squares
Once you have obtained the total square footage of the roof, it needs to be converted into roofing squares. Shingle bundles will typically cover about 1/3 of a square; a square of shingles in roofing is 100 square feet. This means that you can divide the total square footage by 100 to obtain roofing squares.
A roof that measures 1,842 square feet equals 18.42 squares, which would need to be rounded up to 19 when purchasing. Alternatively, a square calculator for roofing can convert your roof square footage to roofing squares.
6. Determine The Shingle Bundles
Next, you will need to determine the number of shingle bundles that must be obtained. A bundle of shingles typically contains material to cover 1/3 of a roofing square. Therefore, multiplying the number of roofing squares obtained in the previous step by three will tell you how many bundles of shingles you must purchase. In our example, 19 x 3 is 57, so you will need 57 bundles of shingles.
7. Round Up By 15%
Many roofs have odd angles that require shingles to be altered to fill the gap. In addition, some shingles may arrive bent or cracked and cannot be used. Therefore, experts recommend purchasing 15% more material than the calculations show in order to account for such issues.
If, for example, you determined that you need 57 bundles of shingles, multiply that by 1.15 to get 65.55 bundles, then round this up to the nearest whole number. In this case, you will need 66 bundles of shingles.
Reach Out To The Northern Virginia Roofing Professionals
Although many home improvement jobs can be carried out as DIY projects, roofing is one task that is best left to the professionals as climbing up on the roof, even just to take measurements, is extremely risky.
Ensure the job is done safely and correctly by trusting the job to the roofing team at Adelphia Exteriors. Contact us today for more information about our residential roofing replacement and installation services.