Commercial roofing is a very different construction specialty than residential roofing. Indeed, few residential roofers have the expertise, experience or tools necessary to install, repair, maintain or replace a commercial building’s roof. Though the term does not specifically refer to a commercial building, but to a style of construction, it is most common that these styles are found on larger structures, including apartment buildings, retail stores, warehouses, etc. Most (but not all) commercial roofs are large and flat, but all have special requirements in order to prevent leaking and internal weather damage.
The most common method is called “hot tar” and consists of layers of tar covered by gravel. This method can be dangerous to install, but continues to be used today. Other methods include rolled roofing, sprayed foams and polyurethane sheeting. Some commercial roofs are done with specially formed metal sheets that interlock to make the result impermeable. In all cases, the goal is to lay down a material which has been melded together to form a continuous, solid sheet that keeps the water from coming through and directs that water to a gutter or opening in the roof. Modern materials and techniques have also provided us with better insulation and more environmentally safe and friendly materials.
Since roof structure is always an important part of a commercial roof, it is best to contact a professional commercial roofer any time you have concerns or needs on a commercial building.