EPDM stands for ethylene propylene diene terpolymer. It is a synthetic rubber roofing material that can be used on both residential and commercial structures with low slopes. The material is comprised of two main ingredients, propylene and ethylene, both of which are derived from natural gas and oil. EPDM roofing can be installed in either white or black, as well as in a variety of widths between 7.5 to 50 feet. EPDM roofing is available in three thicknesses of 45, 65, and 90 mils, and can be attached through ballasting, adhesives, or mechanical attachment. Regardless of the installation method, the seams of the rubber roofing structure are sealed with a liquid adhesive, or in some cases, a specially formulated tape will be used for sealing purposes.