calculate roof square footage 17

https://fast-wiki.win/index.php/How_to_Calculate_Roof_Square_Footage_for_Accurate_Material_Estimates

To calculate roof square footage, you'll need to measure the length and width of each roof plane, including overhangs, then multiply them together for the area. For gable roofs, measure from ridge to eave and from gable end to gable end; for hips, break into rectangles and triangles. Add the areas of all planes, adjusting for pitch by multiplying by a slope factor—use a pitch multiplier table or the Pythagorean theorem to get accurate material estimates.