Roof Drains


There are a number of distinct varieties of roof drains and roof drain system in Pelham, AL and each one is a specific solution to the variety of roof styles and their drainage challenges. You need to consider the kind of roof, its dimensions, and its roof pitch to be able to choose the most suitable drain. You also need to think about the site of the drain, how much rainwater is anticipated and safe practices when selecting a roof drain for a residence or business structure.

Gambrel, dormers, hip and gable roofs shed water because of gravitational force. Flat roofs, on the other hand, collect rain water. Unless the water is routed out and away from the roof , it will create pools of water that may inevitably leak and the amassed weight may subsequently result in damage to the structure. That is the reason that roofs with a slope of less than 2% should have roof drains positioned at the lowest places on the roof in which water pools and need to be uniformly spaced all throughout the roof surface.

Roof Drain Kinds


There are several distinct alternatives of roof drains. They basically fall into 2 categories: flat roof drains and pitched roof drains. Pitched roof rainwater drains normally consist of gutters that collect rainwater that passes via gravity down to the roof periphery. Gutters direct this water in the direction of downspouts which direct the water flow down and far away from the structure or into 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 periphery. They can also be placed on a balcony or terrace. Small holes are cut into the side of the roof structure so that water can empty and drain the roof surface. Scuppers can connect to a downspout, or can be extended so that water is directed away from the structure sides and foundation.

Interior Roof Drains


There are many types of inner drains for flat roofs. These are positioned at low spots in the roof and attach to inner drainage pipes that drive water outside or in to a sewer system. Many versions of inner roof drains have domes, strainers or covers which prevent debris from clogging the roof drain pipe. These types of drains operate via gravity funneling standing water thru the roof drain system. They can be made of PVC, cast iron or cast aluminum.

Siphonic Roof Drains

Siphonic roof drains are a more efficient substitute for gravity drainage. Standard 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 incorporating an engineered baffle to the sump of the drain system it creates a siphonic drain that eliminates air from the system and permits smaller sized pipe diameters to be used. When all of the air is eliminated, a negative air pressure in the tail portion of the drain is set up which attracts rainwater off the roof siphonically. Although 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 system in and around Pelham, Alabama, give us a call. We'd be glad to help.