Is Standing Water on a Flat Roof a Problem

Aside from causing your roof to leak, along with the added damage, standing water on your flat roof can impact the utility, lifespan, performance, and durability of your roofing structure. It doesn’t just damage the affected portion of your roof but can affect the overall integrity of the structure – even including the rest of your home. Due to this reason, many material manufacturers who create flat roofing materials often provide a stipulation in their warranties that count the presence of ponding water on a flat roof as a cause for the warranty to become void. 

Thus, aside from damaging your property, standing water on a flat roof may cost you a lot more for repair since you can’t rely on insurance or warranty coverage.

What is Standing Water on a Flat Roof?

Standing or ponding water on a flat roof is defined in the roofing industry as a situation wherein water from rain, melted snow, or other means stands to remain on the surface of a roof for longer than 2 days.

This often occurs following a storm, heavy rain, or after snowfall when the sun is out and melting the snow. When one of these events occur, water collects in pools or ponds on the roof. However, these pools of water usually drain off after a few hours. In since cases, the water also evaporates. If you notice ponding water on your roof directly following heavy rain, then this is not an issue. Standing water right after rainfall is normal since it takes some time for the water to drain off or evaporate. However, when a period of 48 hours passes and there are still large ponds on your roof, immediate course of action is necessary. As a property owner, you should be aware of the signs that ponding has become an issue. If the ponding lasts more than a couple of days, it is time to call in a roofing professional to discuss options to mitigate any damage to your property.

On an important note: Ponding water is not an imminent threat since roof membranes made of multiple layers of water resistant materials. However, when ignored, standing water can end up causing major and compounding damage over time.

Although immediate leakage is not likely to occur due to ponding water in the first few days, constant ponding can further cause damage to the roof and cause it to deteriorate before its time. It is simply good practice to maintain your roof to the highest standards in order to garner full life expectancy.

Understanding why your flat roof is holding water is the first step to finding a solution. 

What are the Common Causes of Ponding?

Some of the possible reasons behind ponding water on your roof can either be simple to fix problems that require minimal maintenance and repair from your roofer or may not even need the help of your roofer altogether. On the other hand, some causes can also be deep rooted and require major repairs that will definitely need the hands of a certified, skilled, and experienced roofing team. For instance, if you have true structural problems which are not allowing the water to run-off as designed, you may be looking at a challenging situation to resolve.

However, there are many causes to standing water on a flat roof that are easy fixes.

Some of these common causes of standing water include:

  • Improperly installed drains
  • Slope is too low
  • Dented areas 

It is important to check if your roof’s drainage system has been installed properly. A proper drainage and gutter system should be designed to have sufficient water to run towards the gutter and drains. However, if there is any debris obstructing the system, water will start to pool quickly.

Another issue is when the roof’s design itself is set too low. Despite being called a flat roof, a more accurate way to describe most roofs is as a “low-slope” roof. A slight slope is necessary to allow water to drain off the roof. If the roof is completely flat, water will tend to stand still and form ponding more frequently.

Lastly, dented or lowered areas on your roof can become prone to ponding since water will naturally flow and gather on these spaces. These dents or sunken portions may be caused by poor roof design and installation or could be a result of damage from heavy equipment or people walking around on your roof.

No matter what the cause of the standing water, it is essential that you get the help of a roofing contractor to assess the damage and determine the best course of action. The local experts at New Covenant Construction are here to help you to fix any problem with your roofing system.

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