Roof Drains


At this time there are a few different kinds of roof drains and roof drain pipe in Oneonta, AL and each is a specific answer to the variety of roof types and their drainage issues. You should think about the kind of roof, its dimensions, and the roof pitch to be able to choose the right drain. You also should take into consideration the location of the drain, how much rainwater is expected and safe practices when choosing a roof drain for a home or business building.

Hip roofs, dormers, gable and mansard roofs shed rainwater water due to gravity. Flat roofs, on the other hand, accumulate water. Unless the water is guided out and away from the flat roof structure, it will create pools of water that could eventually leak and the amassed weight will subsequently cause structural damage. That is the reason that roofs with a pitch of below two percent should have roof drains located at the lowest areas on the roof in which water pools and should be evenly spread throughout the roof top.

Roof Drain Kinds


There are a number of distinct variations of roof drains. They basically fall into two groups: pitched roof drains and flat roof drains. Pitched roof rainwater drains usually consist of gutters which accumulate rainwater which passes by means of gravity down to the roof edge. Gutters direct this water towards downspouts which direct the water flow down and far away from the structure or into sewers. Flat roof drains are one of three main types: scuppers, inner drains or siphonic drains.

Roof Rainwater Drain Scuppes


Scuppers are located on a roof's perimeter. They can also be installed on a balcony or terrace. Small openings are cut in the side of the roof structure so that rain water can flow out and drain the roof top. Scuppers can attach to a downspout, or can be lengthened to make sure that water is guided off of the structure sides and foundation.

Interior Roof Drains


There are many kinds of inner drains for flat roofs. They are positioned at low places in the roof and connect to interior drainage pipes that direct water outside or in to a sewer system. Many designs of internal roof drains have domes, strainers or covers which prevent debris from obstructing the roof drain pipe. These types of drains work via gravity funneling pooling water thru the roof drain system. They are made from PVC, cast iron or cast aluminum.

Siphonic Roof Drains

Siphonic roof drains are a more effective alternative to gravity drainage. Standard flat roof drainage permits both air and water to enter the drain system producing pipe space occupied by both air and water. By incorporating an engineered baffle to the sump of the drain body it produces a siphonic drain that removes air from the system and permits smaller pipe diameters to be used. When all of the air is removed, a negative air pressure in the tail piece of the drain is set up which pulls rainwater off the roof siphonically. Although used mainly for flat roofs, siphonic drains can also be set up on angled roofs.

If you need more information about flat roof drain or roof drain pipe in and around Oneonta, Alabama, give us a call. We'd be glad to help.