We know enough about the overall measurements of the roof to fill in the missing values. Trapezoids are tricky to get the area measurement of, so were going to split each of them into two triangles and a rectangle: Notice in the image above that the hip roof is made of two triangles and two trapezoids. Once you have these figures, return to the safety of your home.

Roof area = base area / cos Two: Split Tricky Shapes Into Squares And Rectangles Then, use the following equation to find the total area of the roof: Begin by converting the roof pitch to an angle expressed in degrees, using the following formulas: Once you know these values, you will be able to calculate the roof area. You can input it either in degrees, as a percentage or as a ratio of x:12. If you donât know how to calculate it, head to our roof pitch calculator. Roof pitch is the slope created by the rafters. ĭetermine the roof pitch of your house.If the shape of your house is more complex, simply enter the total area into the appropriate box. If your house is rectangular, all you need to do is multiply the length and width of the building. īegin with calculating the area of your house in a plane parallel to the ground.

Therefore, the total area of the roof plan above is 1200 sqft + 800 sqft + 400 sgft = 2400 sqftĮxample 1.2 How Do You Calculate The Roof Area