Roof Drains


At this time there are several distinct kinds of roof drains and roof drain system in Pinson, AL and each is an unique answer to the wide range of roof types and their drainage concerns. You must consider the kind of roof, its size, and its roof pitch to be able to select the most suitable drain. You also should take into consideration the location of the drain, how much rainwater is anticipated and safety when selecting a roof water drain for a house or commercial structure.

Hip roofs, dormers, gable and mansard roofs shed water because of gravitational force. Flat roofs, conversely, accumulate water. Unless this water is guided out and away from the roof , it will most likely develop pools of water that may inevitably leak and the accumulated weight may eventually cause structural damage. That is why roofs with a pitch of less than two percent should have roof drains situated at the lowest spots on the roof in which water puddles and should be evenly spaced throughout the roof surface.

Types of Roof Drains


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

Roof Rainwater Drain Scuppes


Scuppers are situated on a roof's perimeter. Scuppers can also be put in on a balcony or terrace. Small holes 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 can be lengthened so that water is guided away from the structure sides and foundation.

Interior Roof Drains


There are many kinds of inner drains for flat roofs. These are positioned at low spots in the roof and attach to interior drainage pipes that route water outdoors or in to a sewer system. Many models of internal roof drains have domes, strainers or covers which keep trash from blocking the roof drain pipe. These kinds of drains work via gravity channeling standing water through the roof drain system. They are made of PVC, cast iron or cast aluminum.

Siphonic Roof Drains

Siphonic roof drains are a more effective substitute for gravity drainage. Traditional flat roof drainage allows both air and water to go into 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 body it produces 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 set up which attracts rainwater 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 system in and around Pinson, Alabama, give us a call. We'd be glad to help.