Atlas Brown Roof Runoff: Identify the Residue and Drainage Path
Bulletin date: not stated in source
Atlas describes environmental residue that can collect during dry periods and wash onto fascia or siding. The bulletin distinguishes an appearance issue from roof-performance damage and discusses roof-edge drainage
Atlas technical bulletin: Shingle Runoff.
What this means for your roof
Atlas describes environmental residue that can collect during dry periods and wash onto fascia or siding. The bulletin distinguishes an appearance issue from roof-performance damage and discusses roof-edge drainage. Diagnosis should come before cleaning, since other stains can have different causes.
A useful question for your contractor
What is the residue, and can improved drainage keep it off the exterior finishes?
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.
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.