Roof Drains


There are a few different types of roof drains and cast iron roof drain in Helena, AL and each is a specific answer to the wide range of roof types and their drainage challenges. You must consider the type of roof, its dimensions, and the roof pitch to be able to select the most suitable drain. You also may want to take into consideration the site of the drain, what amount of rainwater is anticipated and safety when selecting a roof drain for a residence or commercial structure.

Gambrel, dormers, hip and gable roofs shed water due to gravitational force. Flat roofs, on the other hand, collect rain water. Until this water is guided out and away from the flat roof structure, it will create pools that may eventually leak and the accumulated weight may subsequently result in compromising the integrity of the structure. That is why roofs with a slope of below 2% ought to have roof drains located at the lowest areas on the roof in which water puddles and should be uniformly spaced all throughout the roof top.

Roof Drain Kinds


There are a number of different variations of roof drains. They generally fall into 2 groups: flat roof drains and pitched roof drains. Pitched roof drains usually comprise gutters which collect rainwater that passes via gravity to the roof edge. Gutters direct this water towards downspouts which direct the water flow down and far away from the building or in to sewers. 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 flow out and drain the roof top. Scuppers can attach to a downspout, or can be extended so that water is directed away from the structure sides and foundation.

Interior Roof Drains


There are quite a few different types of inner drains for flat roofs. They are installed at low areas in the roof and connect to interior drainage pipes that route water outside or into a sewer system. Many styles of inner roof drains have domes, strainers or covers that prevent trash from blocking the roof drain pipe. These types of drains operate via gravitational force channeling standing water thru 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 go into the drain system creating pipe space occupied by both air and water. By adding an engineered baffle to the sump of the drain system it creates a siphonic drain which removes air from the system and permits smaller sized pipe diameters to be used. When all of the air is eliminated, a negative air pressure in the tail portion of the drain is established which draws water off the roof siphonically. Although used mainly for flat roofs, siphonic drains can also be installed on angled roofs.

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