GAF describes conditions for a 4-by-4-inch step-flashing alternative, including additional leak-barrier requirements and length tied to shingle exposure.
GAF technical bulletin: The use of 4 / x 4 / step flashing.
What this means for your roof
GAF describes conditions for a 4-by-4-inch step-flashing alternative, including additional leak-barrier requirements and length tied to shingle exposure.
A useful question for your contractor
Ask which complete detail is being used, not just the metal’s nominal size.
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: January 25, 2021. This is the date of the manufacturer source, not a claim that this website guide existed on that date.
Read GAF: The use of 4 / x 4 / step flashing
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.