Toledo Roofers: Article About Roof Drains
A pipe that carries rainwater from a roof drain to the storm sewer piping. From there, it either goes to the storm sewer or a large body of water. Rainwater leaders may also empty out on the ground.
Question and answer courtesy of the Toledo roofing experts from Johnson Roofing in Ohio: What is the difference between a roof drain and a scupper?A roof drain is a drain that is installed into the horizontal surface of a flat roof. A scupper is a drain set at an angle into a parapet on the edge of a flat roof. Scuppers usually drain into downspouts on the side of a building while roof drains send water into rainwater leaders straight through the building into the main storm water drain.
Standing water on a flat roof can cause problems since the longer water is on a roof the more opportunity it has to leak into the structure below. Also, standing water creates a place for mosquitoes to breed and for unwanted mosses and other vegetation to grow. Technically, every roof has some slight slope that will drain water, but many structures have roofs that are very close to being completely flat.
A roof drain carries water from the roof into a pipe that is connected to the storm drain system. Through the storm drain system, it either goes to the city storm sewer, to a retention pond or to a place where it empties out on the ground and soaks into the earth.
In the past, roof drains often drained into the sanitary drain system. Today, in most areas, they are required by code to drain into the storm drain system. Toledo roofers understand local requirements and can explain that most roof drains do not generally drain into gutters where the water can easily overflow.
On the roof, flashing is applied around the drain body and sealed with caulk to prevent water from leaking into the sides of the drain. Roof drains generally have some kind of strainer basket made or iron, aluminum or plastic that sticks up a few inches.
Roofing experts from Johnson Roofing of Toledo Ohio would be happy to answer any questions you have about roof repair or commercial roofing.
The purpose of these baskets is to catch leaves, twigs and other debris and prevent them from entering the drain and getting into the storm water pipes.
Traps are not generally needed on roof drains. However, if the drain is less than 10 feet from a door, window or any other opening, a trap can be used to stop unpleasant smells from coming from the drain.
Water that goes into a roof drain exits on a rainwater leader. Most drains have no hub outlet connections so that they can be hooked up with different types of pipe easily and quickly. Leaders usually run through the building and beneath it into the building's storm drain.
Leaders are usually installed in a building at the same time as the vent pipes and sanitary drainage pipes. In large buildings, leaders and sanitary drainage pipes run parallel to one another in pipe shafts. Like sanitary pipes, leaders must have cleanouts to use in the event they become clogged. Leaders can have a steep grade, or slope, since only water is running down them and not solid waste.
