I'm guessing it is TPO.

They do make EPDM with a white top layer, however, most EPDM is black.

I haven't seen PVC used for roofing in over 15 years, but they may still use it (although EPDM replaced most of the PVC, and TPO is replacing most of the EPDM).

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Jerry Peck, Construction / Litigation Consultant
Construction Litigation Consultants, LLC ( www.ConstructionLitigationConsultants.com )
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