At this time there are a few distinct kinds of roof water drains and cast iron roof drain in Grand Bay, AL and each is an unique answer to the wide range of roof styles and their drainage concerns. You need to consider the type of roof, its dimensions, and its roof pitch to be able to pick the right drain. You also need to take into account the location of the drain, how much rainwater is expected and safe practices when choosing a roof drain for a residence or business structure. Gable, dormer, mansard and hip roofs shed rainwater water because of gravity. Flat roofs, alternatively, collect rain water. Unless this water is routed out and away from the roof , it will most likely develop pools of water that could eventually leak and the accumulated weight will subsequently cause compromising the integrity of the structure. That is why roofs with a pitch of under 2% should have roof drains located at the lowest places on the roof in which water puddles and need to be uniformly spread all throughout the roof surface.
Roof Drain Kinds
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 that accumulate rainwater which passes via gravity to the roof periphery. Gutters channel this water towards downspouts which direct the water flow down and far away from the structure or into sewer lines. Flat roof drains can be one of three primary types: scuppers, inner drains or siphonic drains.
Roof Drain Scuppers
Scuppers are located on the roof's perimeter. They can also be installed on a balcony or terrace. Small openings are cut in the side of the roof structure so water can flow out and drain the roof top. Scuppers can attach to a downspout, or could be lengthened to make sure that water is directed away from the structure sides and foundation.
Inner Roof Drains
There are many types of inner drains for flat roofs. They are positioned at low places on the roof and connect to inner drainage pipes that route water outside or into a sewer system. Several styles of internal roof drains have domes, strainers or covers which keep trash from clogging the roof drain pipe. These types of drains work via gravitational force funneling pooling water through the roof drain system. They can be constructed from PVC, cast iron or cast aluminum.
Siphonic Roof DrainsSiphonic roof drains are a more efficient alternative to gravity drainage. Standard flat roof drainage permits 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 system it produces a siphonic drain that removes air from the system and allows for smaller sized pipe diameters . When all air is removed, a negative air pressure in the tail piece of the drain is set up which draws rainwater 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 cast iron roof drain in and around Grand Bay, Alabama, give us a call. We'd be glad to help.