Flat Roof Rain Water Drainage

Inner roof drains are used on flat roofs and include a low section or channel that collects water and feeds it into a concealed drain that leads to an underground drainage system.

Flat roof rain water drainage.

A light rain or drizzle for example remain remain on a flat roof for a short period of time. A rooftop garden or additional outside living space are the top reasons people choose flat roofs. They are ideal for climates that don t experience large quantities of rain and moisture. The 3 most common drain systems of a flat roof.

Rainfall onto flat roofs needs to be correctly managed to protect the structure against ingress of water. Watch this video on explaining flat roof drains. The drainage system of any roof can be located at the edge or in the middle of the roof. Increasing the angle of a flat roof will always.

There must be some momentum for the water to move into the flat roof drainage system. Gutters are the most commonly used and most cost effective drainage solution for flat roofs. For a large roof it is recommended to have drains placed at multiple locations within the area of the roof. The main benefit of inner drains is that the system is hidden from view.

How water runs off a roof depends on the amount of rainfall and how quickly it needs to drain. Pooling water has adverse effects on a flat roof. They catch rainwater as it rolls off the edge of the roof and divert the water into a downspout that dispenses it a safe distance from the foundation of the building. For larger flat roofs like those used for flats townhouses commercial buildings or schools it s common to have a drain placed inside the roof edge.

Other roof outlets include stainless steel rainwater outlets cast iron rainwater outlets flat roof drainage outlet solutions and brand specific aco roof outlets and caro roof outlets. When using roof rainwater outlets adding leaf and gravel guards is a great way to prevent blockages building up over time. The roof is designed to have a gentle slope towards that drain from where the water is piped away from the walls and foundations. When debris is allowed to collect around drains scuppers or in gutters then the roof is compromised.

No matter the type of drain system for a flat roof as long as it functions correctly this will extend the life of the roof. Flat roof drainage falls into 2 main categories gravity drainage and syphonic drainage. The calculations below are meant for drainage from flat roofs where water are expected to spread over the entire flat roof during rain. Furthermore flat roofs with internal drainage are built to direct water to the central points of the structure with a concave shape the opposite of a pitched roof.

Inner roof drains.