A nail placed above the specified zone may not secure the shingle layers as intended. GAF explains why placement matters and why simply adding surface sealant does not correct every fastening problem.
GAF technical bulletin: High nailing shingles.
What this means for your roof
A nail placed above the specified zone may not secure the shingle layers as intended. GAF explains why placement matters and why simply adding surface sealant does not correct every fastening problem.
A useful question for your contractor
Ask for installation photos that show the product’s marked nailing area and fastener placement.
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 edition: 2021 edition. The PDF pages contain different revision dates within 2021; no exact original release day is asserted.
Read GAF: High nailing 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.