Ponding water on flat roof

Hi, part of my home is a flat roof and come to find out I have holding water! I’m having a contractor come out this Friday to look at it and give me an estimate/solutions.

I also did some research and found products such as gacoroof and other 100% silicone based coatings that claim to fix issues like mine. Are they recommended?

Here’s a pic.


That amount of ponding water is pretty minimal. How long was that pic taken after the last rain? There are no coating that fix ponding water (they just claim their product can it). The only real cure is to remove low spots in the substrate. I really wouldn’t waste my money on that roof, I’d wager 75% of flat roofs have worse ponding water than that!

It was probably about 24 hours… I’m assuming it takes around 48 hours for water to evaporate like that? Assuming it was hot and sunny of course

I’m just worried and want maintence on it because i Just moved into this house and not sure what the insurance will say when they send out an inspector.

If it was only 24 hours then technically it isn’t even ponding water. This is what the national roofing contractors association defines as ponding water: “The criterion for judging proper slope for drainage is that there be no ponding water on the roof 48 hours after a rain during conditions conducive to drying.”

That amount of water on the roof does not require anything done to it unless you like to throw away your money on things that will do nothing to improve the life or performance of your roof. Your roof is epdm membrane, (they make pond liners out of it) it can handle that miniscule amount of water just fine.

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Read the first paragraph.