First determine the area of the roof plan by multiplying the length of the roof by the width. Calculating an area of a triangle when estimating a roof. (1,200 x 1.05 = 1,260 square feet. At first glance, calculating the area of a triangular, sloped surface seems like an extremely tricky task. The do it yourself resource for homeowners from home improvement professionals. I decided to use the pitched roof simply because it is one of the most easiest to analyse. However if you have a PDF file/drawing of the roof plan, it is very easy to get the roof area. (Be sure to include overhangs. Roof A and B can be calculated separately or together. We include on-roof measurements, roof measurements or estimates that can be made from ground level, and several neat tricks using a folding ruler to measure roof angle or slope. Here, our roofing installation experts share two ways for how to calculate roof area: To calculate the area of your roof, first you’ll need to calculate the pitch of it: If you don’t want to do a lot of measuring, you can use your pitch calculation to get an estimated square footage of your roof: If you want to get the exact area measurement for your roof, you can follow these steps: Check out our reviews and let us know how we’re doing. See the image below for more explanation on rise, run and pitch. (For example, if your rise is 4 inches, your roof’s pitch is 4 in 12. Once you have these measurements, you can calculate your roof area as follows: Roof width (m) x rafter length (m) = half roof area (m²) The above calculation estimates the area of half of your roof so you will need to double this to get a final estimate of the full roof area. Every 100 square feet of roof area is referred to as a square, regardless of the type of roofing material. ), Multiply your house length by your house width to get the area. Slope factor is hypothenuse divided by 12: Surface of the roof = house surface x slope factor: Posts are reviewed by an admin beofore showing on the website. To accurately calculate the area of your roof, you must first determine its slope, or pitch. Make light lines on the plan with a pencil. It’s all done on-screen automatically; no manual calculations needed. The informations provided by our website are generic and they should not be used for purchasing construction materials - for that please consult a specialist. To measure the roof, start off by squaring every section of the roof off. 21 Industrial Blvd How about pitch?