The material of a roof may range from laminated glass, aluminum or other metals sheeting and precast   concrete to asphalt singles.  In many parts of the world ceramic tiles have been the predominant roofing material for centuries, both for residential and commercial roofs.

      The construction of a roof is determined by its method of support and how the underneath space is bridged and whether or not the roof is pitched. The pitch is the angle at which the roof rises from its lowest to highest point. Most domestic architecture, except in very dry regions, has roofs that are sloped, or pitched. The pitch is partly dependent upon stylistic factors, but has more to do with practicalities.  There are two parts to a roof, the supporting structure and its outer skin, or uppermost weatherproof layer.  The roof structure is generally supported upon walls.

 

     The durability of a roof is a matter of concern because the roof is often the least accessible part of a building for purposes of repair and renewal, while its damage or destruction can have serious effects on the remainder of the building.  Maintenance of the roof is required to avoid these serious effects or events.