09/09/2025
When our x-ray glasses are on the fritz, and we need to know the composition of a roof, it’s time for core cuts. A simple exercise of cutting a hole, observing the makeup, then installing a patch.
This roofing assembly appears to be a concrete deck that was hot mopped with coal tar. Then two plies of fiberglass reinforced felts were laid, and it was capped with a 90mil cap sheet, all mopped in coal tar.
Understanding the current system guides us in selecting the replacement system.