Flat Roof Ponding Problems Explained

//Flat Roof Ponding Problems Explained

Ponding roof water happens after water is left pooling on a roof for 48 hours after rain. It’s a frequent challenge in commercial roofing. It can cause severe damage to flat roofing systems if the problem isn’t resolved.

To prevent this type of problem in the first place, we recommend that flat roof designs provide enough slope to make sure that the roof drains easily. The recommended roof slope is a minimum of ¼” per foot.

Roof Ponding Dangers

Water can cause incredible amounts of damage to the building structure and roof deck. Weighing in at 63 pounds per cubic foot, a large pool of it packs a punch. When water collects on the roof, it can cause the deck to sag. The deck is made to support a maximum load. If you receive enough water and exceed that point, roof collapse can occur.

Roof Surface & Membrane Damage

The Midwest faces a constant cycle of freezing and thawing. This natural process can slowly wear down the roof membrane and gradually erode your roofs protection. This can cause roof punctures and leaks. Ponding water can also magnify the sun’s rays and burn holes in the roof membrane.

Plant & Mold Growth

Stagnant pooling water combined with the warmth of a sunny day encourages algae and mold growth. The longer this is left on the roof, the more damage that occurs. The plant material can build up and clog roof drains making the problem worse.

Other Ponding Roof Problems

The continual build-up of water, dirt, and pollutants can accelerate roof decay. The pools of water can attract insects and make the environment unsafe for sensitive people. Insurance companies are known for refusing to renew policies if they detect a ponding roof problem.

If you’re experiencing a ponding water problem, don’t let it go. Call us at (815) 385-2102 to schedule a roof inspection. We service all of McHenry and Lake County Illinois.