Roof Drains


There are several distinct varieties of roof drains and roof drain system in Anniston, AL and each one is an unique answer to the variety of roof types and their drainage challenges. You need to think about the type of roof, its size, and the roof pitch to be able to pick the right drain. You also need to take into consideration the location of the drain, how much rainwater is expected and safe practices when selecting a roof water drain for a residence or commercial building.

Gambrel, dormers, hip and gable roofs shed rainwater water thanks to gravitational force. Flat roofs, conversely, accumulate rain water. Until the water is guided out and away from the flat roof structure, it will most likely develop pools of water that may inevitably leak and the amassed weight will subsequently cause structural damage. That is the reason that roofs with a pitch of less than two percent should have roof drains located in the lowest areas on the roof where water puddles and need to be evenly spaced throughout the roof surface.

Roof Drain Types


There are several distinct variations of roof drains. They basically fall into 2 categories: pitched roof drains and flat roof drains. Pitched roof drains normally consist of gutters that collect rainwater that travels via gravity down to the roof periphery. Gutters transport this water towards downspouts which steer the water flow down and away from the structure or into sewer lines. Flat roof drains can be one of three primary types: scuppers, inner drains or siphonic drains.

Roof Rainwater Drain Scuppes


Scuppers are situated on a roof's perimeter. They can also be placed on a balcony or terrace. Small openings are cut into the side of the roof structure so water can empty and drain the roof surface. Scuppers can attach to a downspout, or could be lengthened to make sure that water is guided away from the building sides and foundation.

Inner Roof Drains


There are many kinds of inner drains for flat roofs. They are positioned at low spots in the roof and connect to interior drainage pipes that direct water outdoors or in to a sewer system. Several styles of internal roof drains have domes, strainers or covers that prevent trash from clogging the roof drain pipe. These kinds of drains operate via gravitational force funneling pooling water through the roof drain system. They can be constructed from PVC, cast iron or cast aluminum.

Siphonic Roof Drains

Siphonic roof drains are a more effective substitute for gravity drainage. Standard flat roof drainage allows both air and water to enter the drain system creating pipe space which is occupied by both air and water. By adding an engineered baffle to the sump of the drain body it creates a siphonic drain that eliminates air from the system and allows for smaller sized pipe diameters to be used. When all air is removed, a negative air pressure in the tail portion of the drain is set up which draws water off the roof siphonically. Though used primarily for flat roofs, siphonic drains can also be installed on angled roofs.

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