Roofing materials may be used to protect metal, tiled or asphalt, and are often required to resist weathering, repel dirt and provide durability.  Plastics are also used as roofing materials - see the building plastics page for more information on this product type.

Some roofing and coatings and membranes available contain highly persistent PFAS chemicals.  Some polymer-based membranes have been found to contain halogenated flame retardants, which are persistent, bioaccumulative and/or toxic.