How To Drain a Flat Roof


Since roofs are one of the essential parts of every house, many people focus only on durability and efficiency when roofing. However, it’s possible to add an aesthetic touch to your roof. You can do this by installing a flat roof. Yet, this type of roof has its weaknesses. These faults include cracks, leaks, blisters, and worse still, waterlogging.

Unlike other roof types, a flat roof has a limited slope, so water can’t drain naturally. Large pools of water can destroy your otherwise beautiful roof. So, we’ve written this piece to show you how to drain your flat roof. It’s always best to hire the best Greenville roofers to fix any issues with your roof. Their expertise can help preserve your roof for a long time.

Is It Important To Drain Your Roof?

Yes, you must drain your flat roof. Without such drains, your roof may not last long. Other roof types rely on the force of gravity to remove water. Your flat roof doesn’t have this, so it falls on you to drain it. If you don’t drain your flat roof, any of the issues below could occur.

  • Pooling water can cause leaks and structural damage.
  • Accumulation of debris such as tree branches.
  • If the water freezes in winter, the ice could damage your roof.
  • Large amounts of water can make the roof sag.
  • Unwanted weeds may start growing on your roof.
  • Stagnant water breeds dangerous insects such as mosquitoes and bugs.

How Can I Drain My Flat Roof?

There are many methods and equipment you can use to drain a flat roof. However, we have selected the best three for you. Any of these options can effectively drain your flat roof. So, read on.

  • Interior Drains

Owners of residential and commercial buildings alike love the inner drainage system. It works just how it does in your kitchen sink. You place drainage pipes under your roof at places that collect the most water. Then the water moves through the tubes into a gutter or a downspout at the building’s side. Internal drainages are especially suited for large roofs.


  • The roofs and walls of the building protect the drainage system so it can last longer.
  • In turn, the interior drainage protects the walls and foundation of the building from water damage.
  • The concealed nature of this drainage option retains the aesthetic value of your flat roof.


  • Inner drainages are costly to install
  • They’re difficult to install for already existing buildings
  • Debris can clog the pipes
  • An expert must fix any damage to the system
  • Gutters 

Gutters are the most popular roof drainage system. This drainage system works for practically all roof types. You can install gutters on the building’s side. They then drain water off the building’s foundation and walls.


  • Gutters are inexpensive options, both in installation and maintenance.
  • Regulates water flow and protects your house’s foundation.
  • Protects any wall openings such as windows on the building’s sides.


  • Gutters are usually open, so leaves and debris can block them.
  • Requires continuous maintenance to keep being effective.
  • Lousy weather, ice, and heavy debris can damage the gutters.
  • Scuppers

You can also use a scupper to drain your flat roof. A scupper is that large square or rectangular opening in the walls or curbs of your building. It allows water to flow out from the side of the building. Often, downspouts are installed with the scupper to give direction to the water and protect your walls.


  • Scuppers are cheap to install and maintain
  • They can enhance the building’s appeal
  • Very difficult to clog, especially if very wide
  • Your wall sides are safe


  • If you attach downspouts, debris may clog them.
  • Scuppers aren’t the best options for heavy downpours.

Greenville’s Best Roofers Are at Your Service

There are many options for draining and caring for a flat roof. However, except you’re a professional, you certainly don’t have a wealth of knowledge and experience on how to drain your roof and prevent further damage. Therefore, if you want to protect your flat roof, it’d be best to hand over its care to the best roofing contractors in Greenville.

If you hire Lanier Roofing, you can rest assured that we’ll use all the tricks in the book to drain and preserve your flat roof. We can also offer insight on which of the drainage options are the best for your particular roof. You have a lot to gain and nothing to lose from using our services. So, call us today for a FREE consultation.

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