The definition of a Flat roof is 1-10 degrees but can go up to 12.5 degrees. A Pitched / inclined roof is from 12.5 to 85 degrees. Flat roofing products (2 layer bitumen felt systems) can be used in pitched / inclined roof applications as long as the correct application methods are implemented. However pitched roof, products can only be used down to their designed minimum pitch. This information can be found on the Technical Data Sheets for the variety of IKO Systems and Solutions we offer.