Roof Drains


At this time there are several different kinds of roof water drains and roof drain pvc in Anniston, AL and each one is a specific approach to the wide range of roof types and their drainage concerns. You need to think about the kind of roof, its dimensions, and the roof pitch to be able to choose the correct drain. You also should take into consideration the location of the drain, what amount of rainwater is anticipated and safety when selecting a roof drain for a home or business structure.

Gambrel, dormers, hip and gable roofs shed water due to gravitational force. Flat roofs, alternatively, accumulate rain water. Until this water is routed out and away from the flat roof structure, it will develop pools of water that may eventually leak and the amassed weight may eventually cause structural damage. That is the reason that roofs with a slope of less than two percent should have roof drains located in the lowest areas on the roof in which water puddles and need to be evenly spaced all throughout the roof surface.

Types of Roof Drains


There are a number of distinct alternatives of roof drains. They basically fall into 2 categories: flat roof drains and pitched roof drains. Pitched roof rainwater drains usually comprise gutters that accumulate rainwater which passes by means of gravity down to the roof edge. Gutters transport this water in the direction of downspouts which steer the water flow down and away from the structure or into sewers. Flat roof drains are one of three main types: scuppers, inner drains or siphonic drains.

Roof Drain Scuppers


Scuppers are located on a roof's perimeter. They can also be placed on a balcony or terrace. Small holes are cut in the side of the roof structure so rain water can empty and drain the roof top. Scuppers can hook up to a downspout, or can be extended so that water is guided off of the building sides and foundation.

Inner Roof Drains


There are quite a few different types of inner drains for flat roofs. They are installed at low places on the roof and connect to interior drainage pipes that drive water outdoors or into a sewer system. Several styles of inner roof drains have domes, strainers or covers which keep trash from clogging the roof drain pipe. These kinds of drains operate via gravitational force funneling standing water thru the roof drain system. They are made of PVC, cast iron or cast aluminum.

Siphonic Roof Drains

Siphonic roof drains are a more effective substitute for gravity drainage. Traditional flat roof drainage allows both air and water to go into the drain system creating pipe space which is occupied by both air and water. By incorporating an engineered baffle to the sump of the drain system it produces a siphonic drain that removes air from the system and permits smaller sized pipe diameters . When all air is removed, a negative air pressure in the tail portion of the drain is set up which pulls water off the roof siphonically. Though 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 pvc in and around Anniston, Alabama, give us a call. We'd be glad to help.