Roof Drains


At this time there are a few distinct varieties of roof water drains and roof drain dome in Montevallo, AL and each one is an unique approach to the wide range of roof types and their drainage concerns. You should look at the kind of roof, its dimensions, and its roof pitch to be able to pick the right drain. You also need to think about the location of the drain, what amount of rainwater is expected and safety when choosing a roof drain for a residence or commercial structure.

Hip roofs, dormers, gable and mansard roofs shed water due to gravitational force. Flat roofs, on the other hand, accumulate rain water. Unless this water is guided out and away from the roof structure, it will develop pools of water that may inevitably leak and the accumulated weight may subsequently cause structural damage. That is why roofs with a slope of below two percent should have roof drains positioned at the lowest areas on the roof in which water pools and should be evenly spread all throughout the roof top.

Roof Drain Types


There are several different variations of roof drains. They generally fall into 2 groups: flat roof drains and pitched roof drains. Pitched roof drains normally comprise gutters which collect rainwater which travels by means of gravity down to the roof edge. Gutters channel this water in the direction of downspouts which steer the water flow down and away from the building or into sewers. 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 periphery. They can also be installed on a balcony or terrace. Small holes are cut into the side of the roof structure so that water can flow out and drain the roof surface. Scuppers can attach to a downspout, or can be lengthened so that water is directed away from the building sides and foundation.

Inner Roof Drains


There are many kinds of inner drains for flat roofs. These are positioned at low places on the roof and attach to inner drainage pipes that drive water outdoors or into a sewer system. Several versions of internal roof drains have domes, strainers or covers which keep debris from blocking the roof drain pipe. These kinds of drains work via gravitational force channeling pooling 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. Conventional flat roof drainage permits both air and water to enter the drain system creating pipe space occupied by both air and water. By incorporating an engineered baffle to the sump of the drain system it creates a siphonic drain that removes air from the system and permits smaller sized pipe diameters . When all of the air is eliminated, 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 Montevallo, Alabama, give us a call. We'd be glad to help.