Roof Rainwater Drainage Systems

Where the tube passes by the downspout from the gutter we installed a y fitting and drained the roof water from the gutter system directly into the main drainage line.

Roof rainwater drainage systems.

Keeps water from pouring off of the roof in an uncontrollable manner. As the roof collects rain the water must be transported quickly and safely away by a drainage system. While pitched roofs can rely on gravity to move water flat roofs can t just rely on a typical gravity driven gutter system. To use this calculator input the dimensions of your roof only area connected to rainwater harvesting system and the amount of rainfall in inches.

Can keep water from pooling and building up near the building foundation. For flat sites it may be necessary to drain into a drywell or french drain system or into a pumping chamber that sends drainage to a remote storm drain or drywell. Because the siphoning force helps move the water siphonic drain systems can employ horizontal leaders instead of sloped pipes which rely on gravity alone for drainage. This is a large rainwater catchment system.

High maintenance gutters need continual cleaning and. But don t let it scare you. The 1 100 rain water catchment system. Scuppers are the most effective drainage solution for flat roofs.

The 6 slotted triangle shape is used beneath the aggredrain layer and allows for water to flow freely. Rainwater harvest calculator length. Commercial flat roofs need interior drains and scuppers to collect water instead. Although they do have their benefits they also tend to be favored less due to several reasons.

A system of gutters and downspouts directs the rainwater collected by the roof to the storage cistern. Once all the parts of the drainage system were installed we covered the tubes with several inches of rock. With this system large square openings are made along the edge of the roof that shoot the water away from the side of the building. Protects doorways and window openings.

Commonly used on flat commercial roofs siphonic drains allow for a minimal number of drains and all of the drains can be connected to a single leader. The cistern typically located underground may be constructed of various materials including cinderblock reinforced concrete or precast concrete fiberglass or steel. Rain gutters are the most common drain system in use for all types of roofs. Siphonic drains typically cost more than other drain systems but they work smoothly and require relatively little maintenance.

See french drains for details of handling roof runoff at flat or poorly drained sites.