Atlas Wet Underlayment: Dry and Flatten It Before Shingling
Bulletin date: not stated in source
Atlas says underlayment must be dry, relatively flat and smooth before shingles are installed. Trapped moisture and wrinkles can contribute to visible buckling or blistering
Atlas technical bulletin: Buckled/Wet Underlayment.
What this means for your roof
Atlas says underlayment must be dry, relatively flat and smooth before shingles are installed. Trapped moisture and wrinkles can contribute to visible buckling or blistering. Covering a wet layer with new shingles can conceal the problem rather than resolve it.
A useful question for your contractor
Was the underlayment dry and free of significant wrinkles before the shingles went on?
Ask for the answer to be tied to the actual roof condition and the exact product being installed. Keep the agreed repair or installation detail with your estimate and project photos.
Bulletin dated: not stated in source. The date shown identifies the manufacturer document used for this summary.
Read Atlas: Buckled/Wet Underlayment
This homeowner summary explains the cited bulletin. The complete manufacturer document and current product instructions govern the installation details. A requirement for one manufacturer or product should not be transferred to another without checking.