Roof Drains


There are a few distinct varieties of roof drains and roof drain pipe in Mobile, AL and each is a specific approach to the wide range of roof styles and their drainage challenges. You need to think about the type 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, how much rainwater is expected and safety when choosing a roof water drain for a home or commercial building.

Hip roofs, dormers, gable and mansard roofs shed water thanks to gravitational force. Flat roofs, conversely, collect rain water. Unless this water is directed out and away from the flat roof structure, it will most likely develop pools that could eventually leak and the accumulated weight may eventually result in damage to the structure. That is the reason that roofs with a slope of under 2% ought to have roof drains positioned at the lowest places on the roof where water pools and should be uniformly spread throughout the roof top.

Types of Roof Drains


There are a number of distinct variations of roof drains. They generally fall into 2 groups: flat roof drains and pitched roof drains. Pitched roof drains usually consist of gutters which collect rainwater that passes by means of gravity to the roof periphery. Gutters channel this water in the direction of downspouts which steer the water flow down and away from the structure or in to sewers. Flat roof drains are one of three main types: scuppers, inner drains or siphonic drains.

Roof Drain Scuppers


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

Interior Roof Drains


There are many kinds of inner drains for flat roofs. These are installed at low areas on the roof and connect to inner drainage pipes that route water outdoors or into a sewer system. Several models of internal roof drains have domes, strainers or covers that keep debris from clogging the roof drain pipe. These kinds of drains operate via gravitational force funneling standing water through the roof drain system. They can be made from PVC, cast iron or cast aluminum.

Siphonic Roof Drains

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

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