A rain gutter is a narrow channel, or trough, forming the component of a roof system which collects and diverts rainwater shed by the roof. It is also known as an eavestrough , eaves channel guttering or simply as a gutter.
The main purpose of a rain gutter is to protect a building's foundation by channeling water away from its base. They also help to reduce erosion, prevent leaks in basements and crawlspaces, protect painted surfaces by reducing exposure to water, and provide a means to collect rainwater for later use.
Rain gutters can be constructed from a variety of materials, including cast iron, lead, zinc, galvanised steel, painted steel, copper, painted aluminium, PVC (and other plastics), concrete, stone, and wood.
Water collected by a rain gutter is fed, usually via a downspout (traditionally called a leader or conductor, from the roof edge to the base of the building where it is either discharged or collected.A collection system strategy for water carried from rain gutters may include a rain barrel or a cistern.