Roof Drains


At this time there are a number of different varieties of roof drains and roof drain dome in Huntsville, AL and each is an unique answer to the wide range of roof styles and their drainage concerns. You must consider the kind of roof, its dimensions, and the roof pitch to be able to select the right drain. You also may want to take into account the site of the drain, what amount of rainwater is anticipated and safety when selecting a roof water drain for a house or business structure.

Gable, dormer, mansard and hip roofs shed rainwater water due to gravitational force. Flat roofs, alternatively, collect water. Unless this water is guided out and away from the flat roof structure, it will most likely create pools of water that may eventually leak and the accumulated weight will subsequently result in structural damage. That is the reason that roofs with a slope of less than two percent ought to have roof drains situated in the lowest areas on the roof where water pools and need to be evenly spaced throughout the roof top.

Types of Roof Drains


There are several different variations of roof drains. They basically fall into 2 categories: flat roof drains and pitched roof drains. Pitched roof drains normally comprise gutters which accumulate rainwater that travels 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 can be one of three main types: scuppers, inner drains or siphonic drains.

Roof Drain Scuppers


Scuppers are situated on the roof's perimeter. Scuppers can also be put in on a balcony or terrace. Small openings are cut into the side of the roof structure so that rain 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 off of 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 places on the roof and connect to inner drainage pipes that drive water outdoors or in to a sewer system. Several versions of inner roof drains have domes, strainers or covers that prevent trash from obstructing the roof drain pipe. These types of drains work via gravity channeling pooling water through the roof drain system. They can be made from PVC, cast iron or cast aluminum.

Siphonic Roof Drains

Siphonic roof drains are a more efficient alternative to gravity drainage. Conventional flat roof drainage allows 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 body it creates a siphonic drain which removes air from the system and permits smaller pipe diameters to be used. When all of the air is removed, a negative air pressure in the tail portion of the drain is set up which pulls rainwater off the roof siphonically. Though used mainly for flat roofs, siphonic drains can also be set up on pitched roofs.

If you need more information about flat roof drain or roof drain dome in and around Huntsville, Alabama, give us a call. We'd be glad to help.