Thank you in advance for the great knowledge that this forum brings together. New roof on a single family. The developer said the roof was "rubber," and then insisted it was rubber when i said i thought it looked a lot like a mod bit. Chalk is fine and smooth. The second image is a blow up of the first and you can see some of the roof texture near the seams. There was no crazing, the seams were all holding, and just a little ponding at the valley. My thoughts are that the plastics are hardening from UV rays. I have seen a little powder on mod bit roofs before, but not this heavy, especially because It rained pretty hard here yesterday, so the chalk may have run from the roof and reoccurred. Is this normal aging or is this roof wearing faster than it should be. Click to Enlarge 57.86 KB Click to Enlarge 54.78 KB