Roof Drains


At this time there are a number of different varieties of roof drains and roof drain dome in Madison, AL and each is a specific solution to the variety of roof styles and their drainage concerns. You need to look at the type of roof, its size, and the roof pitch to be able to choose the most suitable drain. You also need to take into consideration the location of the drain, how much rainwater is anticipated and safe practices when choosing a roof drain for a home or commercial building.

Gambrel, dormers, hip and gable roofs shed rainwater water due to gravity. Flat roofs, conversely, accumulate water. Unless the water is routed out and away from the roof structure, it will create pools that may eventually leak and the accumulated weight may subsequently cause compromising the integrity of the structure. That is why roofs with a slope of below 2% should have roof drains situated in the lowest spots on the roof where water puddles and need to be evenly spaced throughout the roof top.

Roof Drain Kinds


There are a number of distinct alternatives 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 that passes via gravity down to the roof periphery. Gutters direct this water towards downspouts which steer the water flow down and far away from the structure or into sewers. Flat roof drains are one of three primary types: scuppers, inner drains or siphonic drains.

Roof Drain Scuppers


Scuppers are situated on a roof's perimeter. Scuppers can also be placed on a balcony or terrace. Small openings are cut in the side of the roof structure so water can empty and drain the roof top. Scuppers can hook up to a downspout, or can be lengthened so that water is directed away from the structure sides and foundation.

Inner Roof Drains


There are many types of inner drains for flat roofs. These are installed at low spots in the roof and attach to inner drainage pipes that route water outdoors or into a sewer system. Many models of internal roof drains have domes, strainers or covers which keep trash from blocking the roof drain pipe. These types of drains operate via gravitational force funneling standing water thru the roof drain system. They are made of PVC, cast iron or cast aluminum.

Siphonic Roof Drains

Siphonic roof drains are a more efficient alternative to gravity drainage. Traditional 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 adding an engineered baffle to the sump of the drain system it creates a siphonic drain which removes air from the system and permits smaller pipe diameters to be used. When all air is removed, a negative air pressure in the tail piece of the drain is set up which pulls 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 roof drain dome in and around Madison, Alabama, give us a call. We'd be glad to help.