Ponding water can occur on all roof types. This can lead to multiple issues, ranging from leaks to mold growth. Ponding water on a flat roof is especially commonplace. We’ll discuss why this is so and what you can do to minimize water buildup.
What Causes Ponding Water on a Flat Roof?
Ponding water is defined as a puddle that remains on a roof for more than 48 hours. Ponding is typical on commercial roofs, since these tend to have flat surfaces, unlike residential roofs with a sharp slope.
There are two main culprits of ponding water on a commercial roof: building degradation and deck deflection.
Flat roofs have multiple layers of hot asphalt, roofing paper, and gravel. The gravel is the outermost layer. This is also the part that withers over the years from UV ray exposure. The eroded gravel leads to a recessed section that enables water accumulation. Continue Reading →