A Primer on Flat Roof Drainage Systems

A Primer on Flat Roof Drainage Systems

Commercial flat roofs are notoriously leak-prone because of their low slope. Water tends to pond on flat surfaces. In today’s post, Northern Pacific Roofing, your local roofing contractor, lists the essential facts about flat roof drainage systems every homeowner needs to know.

The Term “Flat Roof” Is a Misnomer

Flat roofs aren’t actually flat—they’re slightly sloped to promote drainage of rainwater. As such, the drainage system for a flat roof is integrated into its design. While the drainage system primarily relies on gravity to push water towards the drains, different components, such as ridges and valleys, help maintain the flow.

There Are Three Types of Drainage Systems

Here’s a quick overview of the three types:

  1. Interior drains – The drains are usually located at the center of the roof and have strainers that help prevent leaves and other kinds of debris from clogging the pipes. They’re common in large roofs where water tends to pond in the center. Another advantage of this drainage system is that it blends into the background. This makes interior drains a good choice for building owners who are concerned about the appearance of their flat roof.

  2. Scuppers – In case rainwater spills over from the flat roof, scuppers prevent it from drenching the exterior walls of a building. They’re quite useful in areas that experience heavy amounts of rainfall, but might not be the best choice for areas with cold climates.

  3. Gutters – Gutters are the most cost-effective solution. Unlike the other two options, gutters can be attached to any roof.

Routine Flat Roof Maintenance Is a Must

Regardless of the type of drainage system installed on your flat roof, all commercial roofing systems need routine maintenance. As such, it’s important that you have a contractor from a reputable roofing company regularly clear the drains of debris to prevent puddles from forming.

Looking for experienced contractors in your area? Northern Pacific Roofing, a family-run company with more than 20 years of experience, offers a wide range of professional commercial and residential roofing services. To get a free quote, call us at (415) 456-3482 or leave us a message here. We serve homeowners in Petaluma, San Francisco and San Rafael, CA, as well as the surrounding communities.