Drip edge helps direct roof water away from vulnerable perimeter materials. GAF's details depend on edge profile and installation conditions; one overhang rule does not fit every assembly.
GAF technical bulletin: Drip edges and shingles.
What this means for your roof
Drip edge helps direct roof water away from vulnerable perimeter materials. GAF’s details depend on edge profile and installation conditions; one overhang rule does not fit every assembly.
A useful question for your contractor
Ask how the edge metal, starter, underlayment and gutters will work together.
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 revision: February 1, 2021. This is the date of the manufacturer source, not a claim that this website guide existed on that date.
Read GAF: Drip edges and shingles
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.