DIY Home Garden


Guide to Flat Roof Drainage Solutions

As stated by Frisco roofers, most people don’t give a second thought about their roof’s drainage system until they have problems. However, while each roof is different. Moreover, the flat roof presents unique drainage challenges due to not having steep angles for the water to run off naturally.

In this article, we look at some of the best drainage solutions for a flat roof.

Defining Flat Roof Drainage System

If you don’t have adequate drainage on a flat roof, you will experience water damage and water leaks. While nearly all roof drainage systems involve pipes and plumbing, how they’re implemented varies. The three most common drainage systems for flat roofs are the interior drains, scuppers, and gutters. In the next section, we’ll break these down and list the pros and cons of each.

Interior Drains

The interior drain works like a sink for your flat roof. The drain is installed on the center of the roof and water is carried away by pipes away from the building. The plumbing is set inside the building which gives this system its name.

The pros for the interior drain is that since the pipes are inside, they’re protected from the elements and debris. Also, water runs to the center of the roof which reduces the likelihood of damage to the building.

Cons for the interior drain are the cost of installation, and you must clean out the filter regularly at the top of the drain to ensure the water flows freely.


A scupper is a pipe that sticks out at the end of a flat roof. They’re installed on the edges of the roof and water and debris shoot out and go to another gutter where it eventually gets funneled to the ground.

Pros for scuppers are they’re inexpensive and easy to install and very efficient at eliminating water.

The biggest con to the scupper is they’re made useless by ice that blocks the water from flowing. Water that isn’t drained straight away can lead to water damage and leaks.


Gutters are the most common drainage systems and are seen on virtually every building and house. Why? Because gutters normally drain water into pipes that carry it away from the building.

Pros for gutters is they’re inexpensive and easy to install; in fact, most people can install them themselves.

The biggest con of gutters is that while they can handle virtually any form of debris, you must keep them clean; otherwise, they will not be sufficient. Also, gutters clog thanks to leaves, dead birds, pests, and other debris easily, and failing to keep them clean means water damage and roof leaks.

Final Thoughts About Flat Roof Drainage Solutions

As you can see, the flat roof presents many challenges when it comes to adequate water drainage. However, you can find success with one or a combination of the three types above. Keep in mind that to keep your drainage system productive, you must maintain it regularly and ensure that it’s cleaned to keep water and debris free-flowing.

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