Roof Drains


At this time there are a number of distinct types of roof drains and roof drain system in Montevallo, AL and each one is an unique solution to the wide range of roof types and their drainage issues. You must look at the type of roof, its dimensions, and its roof pitch to be able to select the correct drain. You also may want to think about the location of the drain, what amount of rainwater is anticipated and safe practices when selecting a roof drain for a house or commercial building.

Hip roofs, dormers, gable and mansard roofs shed water because of gravity. Flat roofs, alternatively, accumulate water. Until this water is directed out and away from the roof , it will most likely 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 below 2% should have roof drains positioned at the lowest places on the roof where water puddles and should be evenly spread all throughout the roof top.

Roof Drain Types


There are a number of different alternatives of roof drains. They basically fall into 2 groups: flat roof drains and pitched roof drains. Pitched roof rainwater drains normally comprise gutters that accumulate rainwater that passes by means of gravity to the roof periphery. Gutters transport this water in the direction of downspouts which steer the water flow down and far away from the building or into sewer lines. Flat roof drains can be one of three main types: scuppers, inner drains or siphonic drains.

Roof Drain Scuppers


Scuppers are located on a roof's periphery. Scuppers can also be put in on a balcony or terrace. Small holes are cut into the side of the roof structure so water can empty and drain the roof surface. Scuppers can connect to a downspout, or could be extended so that water is guided off of the building sides and foundation.

Interior Roof Drains


There are quite a few different types of inner drains for flat roofs. These are installed at low spots in the roof and connect to interior drainage pipes that direct water outdoors or in to a sewer system. Many designs of inner roof drains have domes, strainers or covers which keep debris from blocking the roof drain pipe. These kinds of drains operate via gravity funneling standing 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 efficient alternative to gravity drainage. Conventional flat roof drainage permits 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 system it produces a siphonic drain that removes air from the system and permits smaller sized pipe diameters . When all of the air is eliminated, a negative air pressure in the tail piece of the drain is established which pulls water off the roof siphonically. Though used mainly 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 Montevallo, Alabama, give us a call. We'd be glad to help.