I'm installing laminated shingles on a house in a 140 mph wind zone in north Florida.

Shingle Rating: You need ASTM D7158 Class H (150 mph) rated laminated shingles. Florida Product Approval or Miami-Dade NOA listing is mandatory. Verify the specific product approval for your exact shingle model.

Nailing (Critical for High Wind):

• Fastener: Ring-shank roofing nails, minimum 12-gauge, 3/8" head diameter. Length must penetrate ¾" into sheathing or through plywood/OSB. Staples are prohibited in HVHZ (High Velocity Hurricane Zone) and strongly discouraged statewide for 140 mph.
• Pattern: 6 nails per shingle (not 4). This is required by FBC R905.2.6.1 for >130 mph zones and most Class H manufacturer instructions.
• Placement: Drive nails 1" above the cutout (or per manufacturer's "high wind" line), 1" from each end, and evenly spaced (approx. 7-7/8" o.c. for standard 39-3/8" shingles). Nails must be flush, not overdriven or angled.
• Decking: Min. 15/32" plywood or 7/16" OSB (FBC R803.2.2). Verify fastener penetration.

Underlayment: FBC R905.1.1 requires two layers of ASTM D226 Type II (No. 30) felt or one layer of approved synthetic (per FL Product Approval) with capped head nails (cap nails) spaced per approval (typically 6" edge / 12" field). Self-adhering membrane (ASTM D1970) at eaves, valleys, ridges, and penetrations.

Code References: FBC 2023 (8th Ed.) R905.2.6.1 (Fasteners), R905.2.4 (Wind Resistance), R905.1.1 (Underlayment), R803.2.2 (Sheathing). Check local amendments.

Bottom Line: Use Class H shingles, 6 ring-shank nails/shingle placed precisely, approved underlayment system. Pull the specific manufacturer's High Wind Application Instructions and the Florida Product Approval sheet for the exact shingle on the job site. Follow the stricter of the two.

For laminated (architectural) shingles in a 140 mph wind zone in north Florida, you must use shingles rated for ASTM D7158 Class H or higher, which is the standard for wind resistance in high-wind areas. Class H shingles are tested to withstand uplift forces equivalent to 150 mph basic wind speed (3-second gust), providing a safety margin for 140 mph zones per the Florida Building Code (FBC) and International Building Code (IBC).

Key Requirements:

1. Shingle Rating: - Must be labeled ASTM D7158 Class H (or equivalent, such as UL 2218 Class 4 for impact, but wind rating is separate). - Verify the manufacturer’s product data sheet explicitly states compliance with ASTM D7158 Class H for 150 mph wind resistance. - Do not rely on marketing terms like “high-wind” or “storm-resistant” without the ASTM D7158 Class H designation.

1. Nailing Requirements (Critical): - Use 6 nails per shingle (not the standard 4) in high-wind zones per FBC Section 1507.2.7 and IBC Section 1507.2.7. - Nail placement: - Standard zone: 1 inch above the cutout, 1 inch from each end. - High-wind adjustment: Add two additional nails — one 1 inch above each end of the shingle (total 6), spaced evenly across the width. - Nails must be roofing nails with a minimum 3/8-inch head diameter and 12-gauge or thicker shank (e.g., 11-gauge smooth shank or 12-gauge ring-shank for better pull-through resistance). - Penetration: Minimum 3/4 inch into sheathing (or through sheathing into framing if using OSB/plywood < 7/16”). - Drive nails flush — not overdriven (which cuts shingle) or underdriven (which leaves nail head proud and risks wind lift).

1. Additional Best Practices: - Use self-sealing asphalt shingles with factory-applied adhesive strips — ensure they’re warm enough to activate (above 40°F) during installation. - Install ice and water shield along eaves, rakes, valleys, and penetrations (FBC requires it in high-wind zones). - Follow manufacturer’s specific high-wind installation instructions — some brands (e.g., GAF Timberline HDZ, Owens Corning Duration) have proprietary nailing zones and enhanced sealant strips for 150+ mph ratings.

Warning: If the roof deck is compromised, sheathing is inadequate, or you’re unsure about fastening into rafters/trusses, consult a licensed roofing contractor or structural engineer. Improper nailing is the #1 cause of shingle failure in hurricanes.

*Sources: FBC 2023 (based