Roof Drains


At this time there are a number of distinct varieties of roof drains and roof drain pan in Phenix City, AL and each one is a specific approach to the wide range of roof types and their drainage concerns. You must consider the kind of roof, its size, and its roof pitch to be able to select the correct drain. You also should take into account the site of the drain, what amount of rainwater is anticipated and safe practices when choosing a roof water drain for a residence or business building.

Gambrel, dormers, hip and gable roofs shed water because of gravity. Flat roofs, conversely, collect rain water. Until this water is directed out and away from the roof structure, it will most likely create pools of water that may eventually leak and the accumulated weight will eventually result in compromising the integrity of the structure. That is the reason that roofs with a slope of below 2% should have roof drains located in the lowest places on the roof in which water pools and need to be evenly spaced throughout the roof top.

Kinds of Roof Drains


There are a number of distinct alternatives of roof drains. They generally fall into 2 categories: flat roof drains and pitched roof drains. Pitched roof drains usually consist of gutters that collect rainwater which passes by means of gravity to the roof edge. Gutters channel this water towards downspouts which direct the water flow down and far away from the building or into sewers. Flat roof drains are one of three main types: scuppers, inner drains or siphonic drains.

Roof Drain Scuppers


Scuppers are situated on a roof's periphery. They can also be installed on a balcony or terrace. Small holes are cut in the side of the roof structure so that rain water can flow out and drain the roof top. Scuppers can connect to a downspout, or could be lengthened so that water is directed away from the structure sides and foundation.

Inner Roof Drains


There are many types of inner drains for flat roofs. These are positioned at low areas on the roof and attach to inner drainage pipes that route water outdoors or into a sewer system. Many styles of inner roof drains have domes, strainers or covers that keep debris from blocking the roof drain pipe. These kinds of drains operate via gravity funneling 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 alternative to gravity drainage. Traditional flat roof drainage allows both air and water to enter the drain system producing pipe space which is occupied by both air and water. By incorporating 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 of the air is removed, a negative air pressure in the tail piece 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 pan in and around Phenix City, Alabama, give us a call. We'd be glad to help.