Roof Drains


At this time there are a few distinct varieties of roof drains and roof drain pvc in Alabaster, AL and each is a specific answer to the wide range of roof types and their drainage challenges. You should think about the kind of roof, its size, and the roof pitch to be able to pick the most suitable 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 home 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. Until the water is guided out and away from the flat roof , it will most likely create pools that could eventually leak and the accumulated weight may eventually result in structural damage. That is why roofs with a slope of less than 2% should have roof drains positioned at the lowest spots on the roof where water puddles and should be evenly spaced all throughout the roof surface.

Kinds of Roof Drains


There are several different variations of roof drains. They basically fall into two groups: flat roof drains and pitched roof drains. Pitched roof rainwater drains usually consist of gutters which collect rainwater that travels by means of gravity down to the roof edge. Gutters direct this water in the direction of downspouts which steer the water flow down and away from the structure or in to sewer lines. Flat roof drains are one of three primary types: scuppers, inner drains or siphonic drains.

Roof Drain Scuppers


Scuppers are located on a roof's perimeter. They can also be installed on a balcony or terrace. Small holes are cut into the side of the roof structure so that rain water can flow out and drain the roof top. Scuppers can connect to a downspout, or could be extended 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 connect to inner 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 debris from clogging the roof drain pipe. These types of drains work via gravitational force funneling 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 effective alternative to 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 system it creates a siphonic drain that 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 portion of the drain is established which attracts rainwater off the roof siphonically. Although 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 pvc in and around Alabaster, Alabama, give us a call. We'd be glad to help.