Roof Drains


At this time there are several distinct kinds of roof drains and roof drain pan in Oxford, AL and each is an unique approach to the variety of roof styles and their drainage issues. You should look at the kind of roof, its dimensions, and its roof pitch to be able to select the right drain. You also need to take into consideration the location of the drain, what amount of rainwater is anticipated and safe practices when selecting a roof drain for a residence or commercial structure.

Hip roofs, dormers, gable and mansard roofs shed rainwater water thanks to gravitational force. Flat roofs, conversely, accumulate rain water. Until the water is directed out and away from the flat roof structure, it will create pools of water that could inevitably leak and the accumulated weight may eventually result in damage to the structure. That is the reason that roofs with a slope of less than two percent should have roof drains situated in the lowest spots on the roof in which water pools and need to be uniformly spaced all throughout the roof top.

Roof Drain Types


There are several different variations of roof drains. They basically fall into two groups: pitched roof drains and flat roof drains. Pitched roof drains usually comprise gutters that collect rainwater that travels via gravity to the roof edge. Gutters direct this water in the direction of downspouts which direct the water flow down and away from the building or into sewer lines. Flat roof drains are one of three main types: scuppers, inner drains or siphonic drains.

Roof Rainwater Drain Scuppes


Scuppers are located on the roof's periphery. Scuppers can also be placed on a balcony or terrace. Small holes are cut into the side of the roof structure so rain water can flow out and drain the roof surface. Scuppers can attach to a downspout, or could be extended to make sure that water is directed away from the building sides and foundation.

Inner Roof Drains


There are many kinds of inner drains for flat roofs. These are installed at low spots on the roof and connect to interior drainage pipes that direct water outdoors or into a sewer system. Many designs of internal roof drains have domes, strainers or covers which keep debris from blocking the roof drain pipe. These kinds of drains operate via gravity funneling pooling water through the roof drain system. They are constructed 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 allows both air and water to go into the drain system producing pipe space which is occupied by both air and water. By adding an engineered baffle to the sump of the drain system it creates a siphonic drain which eliminates air from the system and permits smaller pipe diameters . 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. Although used mainly for flat roofs, siphonic drains can also be installed on pitched roofs.

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