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Flat Roof Water Management

This foam roof has just been completed and gleans bright in the Valley's sunshine.

Did you know that monsoon season in Arizona lasts from June to September? Heavy rains, wind, and hail can cause significant roof damage.
Your flat roof might be more at risk for roof water and leaks after heavy storms as water and excess debris increase strain on your roofing materials. While regular flat roof maintenance from a professional company can help you maintain your roof year-round, there are also other changes you might make to ensure a long-lasting roof.
Are you still interested? Luckily, we have a must-read article you don’t want to miss out on. Keep reading on and learn more about how to prevent ponding water and other flat roof problems starting today.


Flat Roof Places Most Likely to Leak

Any vulnerable spot on your roof is prone to leaks. However, since flat roofs have less drainage than steeper pitched roofs, you might experience leaks around flashing, rooftop HVACs, parapet walls, and more.
The age of your roof and other previous damage might also pose a higher risk for leaks. For example, flat roofs older than 25 years might need replacing if constructed from EPDM.


Penetrations are holes purposefully made in your roof for equipment. Flat roofs also rely on penetration for adequate ventilation and/or roof drainage. Some of the most common penetrations include plumbing vents, chimneys, or AC/HVAC units.
These areas are also prone to leaking if they are not correctly sealed. The best way to check for leaking or damage around penetrations is through regular professional maintenance and inspection. Most experts recommend having a professional roofing company check your flat roof annually.


Roof scuppers are primarily used with flat roofs. While flat roofs do have a small slope to help with water drainage, scuppers are devices that assist with adequate drainage. However, scuppers can also pose a threat to roof damage.
If not properly maintained, scuppers can become clogged and increase ponding water risks. You can regularly check your scuppers or hire a professional company to maintain and clean your scuppers after heavy storms.

Parapet Walls

Years ago, parapet walls were used as a defense mechanism. It is an additional wall on the rooftop that protects buildings from attacks.
Now, parapet walls are mainly used for cosmetic appearances. Other uses for parapet walls are protection for you or other workers or stepping onto your roof who are at risk of falling.
It can also act as a barrier to debris or wind. Parapet walls could increase flat roof leaks if debris builds around the base of the wall and is not regularly cleaned after severe storms.


Seams And Patches

Flat roof seams and patches are integrity issues on your roof. Poor installation and maintenance can cause lasting issues and costly repairs. Always use a qualified company for your flat roof installation to avoid issues with leaking seams.

Types of Flat Roof Drains

There are three primary flat roof drains: gutters, scuppers, and inner drains. Drainage is important for your flat roof to prevent ponding water. They also help redirect water away from your house and foundation.

1. Gutters

Gutters are one of the most popular and affordable draining systems. It catches rainwater and directs it away from your roof and foundation. Gutters benefit your roof, walls, and windows from damage.

2. Scuppers

Wider scuppers are less easily clogged and are ideal for flat roofs. However, scuppers are best used with other techniques since heavy rain or storms can render them ineffective. In some instances, you may need to also install downspouts.


3. Inner Drains

Inner drains are primarily used for commercial buildings. They are attached to your roof and connected to inner drains that redirect water away from a building. Since these drains are smaller, they are prone to clogs and must be regularly checked.


Best Ways to Prevent Roof Water

Having a professional company install your roof ensures the best long-term success. Other ways to prevent roof water are:
– Install drains
– Add spray foam
– Schedule annual maintenance

While you’ve already read how installing drains and scheduling annual maintenance is important, you should consider spray foam. Polyurethane foam is applied onto the entire surface of your roof and seals cracks or crevices. It also prevents UV ray damage from penetrating layers below your roof.