A roof shingles estimate helps us to estimate the number of shingles to order when laying a new roof. Either a professional roofing estimator or a contractor will let you know the number and quantity of roofing shingles that you need for a given job after taking relevant measurements of your roof. There are several methods to do this. Here we will explore the more common methods.
First, let’s understand how the shingles are packaged and sold. Shingles are sold in bundles. For example take the 3-tab shingles packed in bundles. Three of these bundles will generally cover one roofing square. Roofing Square is the term used in roofing industry to denote 100 square feet. The shingles are packaged in plastic or paper and can easily be transported by one person. The shingles that weigh more may be packed with less shingles per roofing square. So, you will need more bundles per roof square.
The roof shingles estimate will help us to find out how many of the shingles or bundles you need to cover the roofing area. You could use two methods to do this. The measurement method is one and the other is the sheet-count method. In the measurement method either you or someone else has to climb the roof and measure every plane where the roofing shingles will go. Suppose you have a rectangular roof then it is easy to measure the length and width and just multiply both to get the required area.
For sloping roofs and other shapes it is a little more difficult to arrive at the area in straightforward way. You need to adopt indirect estimation methods. First measure the floor area making suitable provision for overhang. Next, for slopes you have different area multipliers. These numbers when multiplied with the floor area gives an estimate of the roofing area. There are 3 different slope multipliers depending on whether your roof is low, medium or a steep roof.
The sheet count method on the other hand uses a simpler technique than actual roof measurement. It uses sheet panels which are of standard 4 * 8 measures. The roof is simply sheathed with these sheets and then you count the number of sheets needed to cover the roof. In some parts of the roof the panels will have to be cut to accommodate the shape of the roof. To arrive at the roof area, add up the full panels and what’s remaining after the cuts on the remaining panels. This is much quicker and simpler method to arrive at the area of an irregular roof.
Also, with the sheet method, all you have to do count the number of panels and you can order the bundles of shingles based on that number of panels. This is a simple and easy way to arrive at the area. It may be a crude method but is very effective and fast.
Another method that has been frequently used and works for homes with old roofs is to simply count the number of shingles on your roof. Just count the number of rows from eaves to ridge. Also, count the number of tabs from edges to eaves. Each tab is one foot in length. The exposed area of each course is 5 inches. Multiplying the numbers gives you the area of shingles needed.