Common Flat Roof Issues

Be Aware

Flat roofs have built-in design and installation factors that can often lead to performance problems and a shorter life span than you might expect.  There are several common flat roof issues to be aware of.

Top 3 Common Flat Roof Issues



This is the most frequently occurring problem on any kind of a residential flat roof. It usually happens due to ponding water that stands longer than 48 hours, after the most recent rain showers. Usually, moisture gets through at the seams or flashings. It can also come from clogged drains, chimneys, skylights, parapets and other types of penetrations on the roof. Its less common to have a leak from some sort of puncture. If moisture gets under the membrane and into the sheathing, mold and rot can start to form. This is especially likely in areas with lots of rain and severe storm frequency.


Shrinking and Deteriorating Materials

One of the most common problems for EPDM membranes is shrinkage. When rubber shrinks, it can pull down parapet walls, drip edges or even a chimney. This is more probable on a larger building, and on a property where the membrane wasn’t properly attached or installed.


Damage Caused by Foot Traffic

Another issue, especially for flat roof decking and commercial buildings is heavy foot traffic. Maintenance personnel (mainly HVAC contractors) and other random visitors going out on the roof, dropping tools, walking over fasteners, thus puncturing the membrane and causing other damages that need to be repaired.

When Should You Replace Your Flat Roof?

Replacing your flat roof can be a costly and time consuming project, and it should, in most instances, be your last resort. Just because your roof is leaking in a few spots doesn’t mean it necessarily must be replaced.

Two Scenarios That Warrant A New Install

The Age of the Roof
When the original material has gotten to the end of its lifespan, your best option is replacing it. Depending on the type of material your roof is made of, your local weather situation, as well as how you’re keeping up with routine maintenance, this life-cycle may vary, as we have discussed above. Since EPDM has seams that are prone to allowing moisture to get through, they will have a lot of issues in locations that have heavy and frequent rain storms. TPO may not live up to its fullest lifespan in geographic locations with high heat and drastic temperature fluctuations.

Poor and Faulty Installation
Unfortunately, installation issues happen way too much. This is the biggest source of all the other issues, including leaks. If you’re constantly fixing a fairly new roof, it probably indicates that it was not installed properly. Some of these can be rectified by a professional roof repair contractor, but their will be some that can’t be. This is why getting a thorough, professional inspection with an experienced roofer is so important.

If installation problems can’t be fixed, the best option will be replacing the faulty roof. Otherwise, you’ll just keep dumping more and more money into a roof that will never perform as its supposed to. If you find that there is wet insulation, it cannot dry out on its own and can cause mold issues and structural damage that will be much more expensive to fix than putting on a new roof, or replacing a large portion of the original one.

If you can afford it, choose a premium material like PVC. While its more expensive than other single ply choices, once you install it, you won’t have to worry about leaks and other problems again for a long time. PVC has hot air-welded seams that don’t come apart, and will remain resistant to water. It’s also an Energy Star rated, cool material, that reflects the sun’s heat, which will save you a lot of money on energy costs as you live in the property.

An Inspection is the Most Important First Step

To find out whether you should do a roof leak repair or replace it with a new membrane, find a professional, experienced roofing contractor to perform a thorough inspection. Be sure you hire an experienced pro, because a plain general contractor or an asphalt shingles expert won’tt know all the little details and complexities of these flat roof materials. They might give you poor recommendations that will cost you even more money and time to fix in the future.

During the inspection, your roofing contractor should include checking:

  • Seams
  • Flashings
  • Attachment points
  • Check for cracks at joints and corners, around chimneys and ventilation slits.
  • Assess any damage: deterioration, punctures, aging, leakage, ponding water, etc

It’s also very important that they do a test-cut (through the material to check what is under the top layer). A lot of times, mold and rotted sheathing underneath the top layer is not visible on the surface.

Emergency Roof Repair Contractors

Mikku and Sons Roofing has been helping residents throughout Phoenix since 2001. Our experienced and friendly crew members can inspect your roof and help you get it ready for the monsoon season to help you reduce the risk of damage. But, if your roof does have damage due to monsoon storms, we are ready to help you with quick and complete roof repair. We have experience in all types of roofs, including tile, shingle and flat roofs on both personal residences and commercial property. We are fully licensed and insured and make it our mission to provide quality workmanships and exceptional service.

Call us today at (623) 465-1068 to find out how we can help you prepare your roof for the coming monsoon season or to repair it after a storm.

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