Rain gutter

A rain gutter, eavestrough, eaves-shoot or surface water collection channel is a component of a water discharge system for a building. It is necessary to prevent water dripping or flowing off roofs in an uncontrolled manner for several reasons: to prevent it damaging the walls, drenching persons standing below or entering the building, and to direct the water to a suitable disposal site where it will not damage the foundations of the building. In the case of a flat roof, removal of water is essential to prevent water ingress and to prevent a build-up of excessive weight. Water from a pitched roof flows down into a valley gutter, a parapet gutter or an eaves gutter. An eaves gutter is also known as an eavestrough (especially in Canada), spouting in New Zealand, rhone (Scotland), eaves-shoot (Ireland) eaves channel, dripster, guttering, rainspouting or simply as a gutter. The word gutter derives from Latin gutta (noun), meaning "a droplet". Guttering in its earliest form consisted of lined wooden or stone troughs. Lead was a popular liner and is still used in pitched valley gutters. Many materials have been used to make guttering: cast iron, asbestos cement, UPVC (PVCu), cast and extruded aluminium, galvanized steel, wood, copper, zinc, and bamboo. Gutters prevent water ingress into the fabric of the building by channelling the rainwater away from the exterior of the walls and their foundations. Water running down the walls causes dampness in the affected rooms and provides a favourable environment for growth of mould, and wet rot in timber. A rain gutter may be a: Roof integral trough along the lower edge of the roof slope which is fashioned from the roof covering and flashing materials. Discrete trough of metal, or other material that is suspended beyond the roof edge and below the projected slope of the roof. Wall integral structure beneath the roof edge, traditionally constructed of masonry, fashioned as the crowning element of a wall. A roof must be designed with a suitable fall to allow the rainwater to discharge.