Fiberglass shingles are a popular roofing option known for their durability and resistance to moisture, thanks to their fiberglass mat base coated with asphalt and surface granules. Proper nailing is crucial to ensure they stay secure against wind, rain, and other elements. The general nail pattern involves placing nails just above the cutout or exposure area, within the designated nailing strip of each shingle. This placement holds shingles firmly while allowing for proper water shedding. Typically, four nails per shingle are standard for most installations, but this can increase to six nails in high-wind areas. Nails should be driven straight and flush with the shingle surface, avoiding over- or under-driven nails, which can cause shingle damage or loosening. Using the right fasteners—usually corrosion-resistant roofing nails with smooth shanks about 12-14 gauge and 1 ¼ to 1 ½ inches long—is essential for a secure hold without damaging the shingle mat.
You can do some simple checks yourself to see if your shingles are properly fastened. After a storm or heavy wind, inspect the roof from the ground with binoculars for any lifted edges or missing shingles. On an accessible roof, carefully lift a loose shingle and gently check the nail placement—are nails driven through the designated nail line? Nails should be straight and flush, not bent or missing. If you notice nails that are overdriven or the shingles are pulling away, it’s time to call a professional. When you contact a contractor, ask, “Can you show me your nail pattern and explain how it meets local wind codes?” and “What type of nails and fasteners do you use to ensure my warranty stays valid?” This ensures the roofer follows manufacturer guidelines and local building codes, which can affect insurance and warranty coverage.