The proper flat roof drainage system can help a roof’s integrity. Flat roofs have a long history in North America, especially in regards to commercial construction. However, flat roofs depend greatly on proper drainage of rain and snowmelt to preserve their integrity. Without it, pooling water can occur and cause leaks, deterioration in the roof membrane and ice formation during winter. Here are three types of drainage systems that are the best fit for flat roofs.

Gutters

Everyone has seen a gutter on the exterior on just about any building or structure. Gutters are open pipes that attach to the outer edges of roofs and collect rainwater as it drains off the roof and carries it away from the building or structure. They are the most cost-effective drainage solution since they can be attached to a finished roof without having to modify a roof itself. Gutters are also good for dealing with different levels of rain and snow.

Interior Drains

An interior drain system is composed of drains placed at stretches near the center of the roof and an internal network of gutters and pipes that move the water to the exterior of the building. Often, drains are topped by a strainer–as one would see in their kitchen sink–to prevent debris such as leaves and small twigs from reaching the inside of a drain. This system is often a good solution for large roofs on which water tends to collect at the center. They are aesthetically pleasing because all of the components are located on the roof and invisible to someone looking at it from the outside. However, these tend to be more costly to install than exterior drainage systems and represent a significant investment.

Scuppers

A scupper is an outlet placed on the edges of the roof that project water that drains off the roof away from the building. Scuppers keep the walls of buildings dry and prevent the foundation from becoming destabilized by too much exposure to water. This option can be the most cost-effective than inner drains, but they work best when all of the water is directed to them using a tapered insulation system or a sloped structure. They are a good solution for areas that frequently get heavy rains, but are not ideal for dealing with snowmelt.

The decision of what type of drainage system is best for one’s business or facility should be determined by one’s engineer or building design team. One should always make sure that the roofing contractor they hire is experienced best when all of the water is directed to them using a tapered insulation system or a sloped structure. They are a good solution for areas that frequently get heavy rains, but are not ideal for dealing with snowmelt.

Shoreline Roofing & Exteriors is a Victoria flat roof installer and repair company and has extensive experience with flat roofs. If one has any questions about their flat roof roofing, please give us a call and we’ll fill one in on our experience with flat roofs and their drainage systems.