Asphalt Shingles

Roofing Types

Asphalt Shingles in Los Angeles

Originally, metal roofs were made of corrugated galvanized steel: a wrought iron–steel sheet was coated with zinc and then roll-formed into corrugated sheets. Another approach is to blend zinc, aluminum, and silicon-coated steel. These products are sold under various trade names like “Zincalume” or “Galvalume”. The surface may display the raw zinc finish, or it may be used as a base metal under factory-coated colors. Another metal roofing product comes in a rolled form of various widths of so-called standing seam metal. The material is “seamed” together using a special roof seaming machine that is run vertically up the panel to seal the joints and prevent water intrusion.

Metal tile sheets can also be employed. These are usually painted or stone-coated steel. Stone coated steel roofing panels are made from zinc/aluminium-coated steel with an acrylic gel coating. The stones are usually a natural product with a colored ceramic coating. Stainless steel is another option. It is usually roll-formed into standing seam profiles for roofing; however, individual shingles are also available. Other metals used for roofing are lead, tin and aluminiumand copper.
Copper is used for roofing because it offers corrosion resistance, durability, long life, low maintenance, radio frequency shielding, lightning protection, and sustainability benefits. Copper roofs are often one of the most architecturally distinguishable features of prominent buildings, including churches, government buildings, and universities. Today, copper is used in not only in roofing systems, but also for flashingsand copings, rain gutters and downspouts, domes, spires, vaults, and various other architectural design elements. At the Lyle Center for Regenerative Studies in Pomona, California, copper was chosen for the roofing on regenerative principles: if the building were to be dismantled the copper could be reused because of its high value in recycling and its variety of potential uses. A vented copper roof assembly at Oak Ridge National Laboratories (U.S.) substantially reduced heat gain compared with stone-coated steel shingle or asphalt shingle, resulting in lower energy costs.