At this time there are several different kinds of roof drains and roof drain downspout in Bessemer, AL and each is a specific answer to the variety of roof styles and their drainage concerns. You must look at the kind of roof, its dimensions, and the roof pitch to be able to choose the correct drain. You also need to think about the site of the drain, how much rainwater is expected and safe practices when selecting a roof water drain for a house or business building. Gambrel, dormers, hip and gable roofs shed water due to gravity. Flat roofs, conversely, accumulate water. Unless the water is directed out and away from the roof , it will most likely develop pools that may inevitably leak and the amassed weight will eventually result in compromising the integrity of the structure. That is why roofs with a pitch of under 2% should have roof drains positioned at the lowest areas on the roof in which water puddles and should be evenly spaced all throughout the roof surface.
Roof Drain Kinds
There are a number of distinct alternatives of roof drains. They basically fall into two categories: flat roof drains and pitched roof drains. Pitched roof drains usually consist of gutters which collect rainwater that travels by means of gravity down to the roof periphery. Gutters direct this water in the direction of downspouts which route the water flow down and far away from the structure or into sewer lines. Flat roof drains are 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 into the side of the roof structure so water can flow out and drain the roof surface. Scuppers can connect to a downspout, or can be extended to make sure that water is directed away from the building sides and foundation.
Inner Roof Drains
There are many types of inner drains for flat roofs. They are installed at low areas in the roof and attach to interior drainage pipes that direct water outside or in to a sewer system. Many versions of internal roof drains have domes, strainers or covers which prevent debris from clogging the roof drain pipe. These types of drains operate via gravity channeling pooling water through the roof drain system. They are constructed from PVC, cast iron or cast aluminum.
Siphonic Roof DrainsSiphonic roof drains are a more effective substitute for gravity drainage. Conventional flat roof drainage permits both air and water to enter the drain system creating pipe space 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 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 installed on pitched roofs.
If you need more information about flat roof drain or roof drain downspout in and around Bessemer, Alabama, give us a call. We'd be glad to help.