If you can see a black circle forming around your roof vents, typically on the north side of the roof, you likely have a mold problem in your attic. When the spores go airborne they are carried out of the attic with the super-heated air and will catch or deposit on the roofing around the vents. This is an urgent issue that should be dealt with soon. Call 3Rs Construction and we will send one of our trained mold experts to review your situation and provide some options to remediate your attic before the damage gets out of control.