Roof Drains


There are a number of distinct kinds of roof drains and cast iron roof drain in Montgomery, AL and each one is a specific answer to the variety of roof styles and their drainage concerns. You need to think about the kind of roof, its dimensions, and the roof pitch to be able to select the correct drain. You also need to take into account the site of the drain, how much rainwater is anticipated and safe practices when selecting a roof water drain for a home or business building.

Gambrel, dormers, hip and gable roofs shed water thanks to gravitational force. Flat roofs, alternatively, collect water. Unless the water is guided out and away from the flat roof structure, it will most likely create pools that may inevitably leak and the amassed weight may eventually cause compromising the integrity of the structure. That is why roofs with a slope of under two percent should have roof drains positioned in the lowest areas on the roof where water puddles and should be evenly spread all throughout the roof surface.

Kinds of Roof Drains


There are several different variations of roof drains. They basically fall into two categories: pitched roof drains and flat roof drains. Pitched roof drains usually comprise gutters that collect rainwater which passes via gravity to the roof edge. Gutters direct this water in the direction of downspouts which direct the water flow down and far away from the structure or in to sewer lines. Flat roof drains can be one of three main types: scuppers, inner drains or siphonic drains.

Roof Drain Scuppers


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

Inner Roof Drains


There are quite a few different types of inner drains for flat roofs. These are installed at low areas in the roof and attach to interior drainage pipes that direct water outside or into a sewer system. Several versions of inner roof drains have domes, strainers or covers which prevent trash from obstructing the roof drain pipe. These types of drains operate via gravitational force channeling standing water through the roof drain system. They are constructed from PVC, cast iron or cast aluminum.

Siphonic Roof Drains

Siphonic roof drains are a more effective alternative to gravity drainage. Conventional flat roof drainage permits both air and water to go into the drain system producing 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 that eliminates air from the system and permits smaller sized pipe diameters . When all air is removed, a negative air pressure in the tail portion of the drain is established which attracts water off the roof siphonically. Although 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 cast iron roof drain in and around Montgomery, Alabama, give us a call. We'd be glad to help.