Asphalt Shingle Nailing Pattern

The nailing pattern is the number and position of fasteners in each asphalt shingle. It is one of the most important factors in wind resistance, and incorrect nailing is a common reason manufacturers decline warranty claims. Manufacturers print a nailing line or zone on the shingle and publish the pattern in their installation instructions.

Number of nails

• Standard: four nails per strip shingle is the usual code and manufacturer minimum.
• High wind: six nails, as manufacturers specify for high-wind installations; local codes in high-wind regions may also require them.
• Steep slopes and mansards: one manufacturer defines steep slope as 21 in per foot (about 60 degrees) or more and requires six nails plus hand-sealing with spots of asphalt cement.

Placement

Nails go in the manufacturer's nailing zone, which on laminated shingles is placed so the nail passes through both the upper and lower layers where they overlap. One manufacturer's four-nail layout places nails about 1 in from each end and about 13 in from each end, on a line 7 3/8 in below the top edge. Nails should be at least 2 in from joints or cutouts in the shingle below.

"High nailing", where nails are driven above the zone, is a frequent defect: the nail may miss the underlying course and the shingle can pull free.

Nail specification

Item	Typical requirement
Material	Galvanized steel, stainless steel or aluminium roofing nails
Shank	12 gauge minimum (some manufacturers allow 11 gauge)
Head	3/8 in (9.5 mm) minimum
Penetration	3/4 in (19 mm) into the deck, or through thinner sheathing

The IRC specifies roofing nails for asphalt shingles, so staples are not a permitted substitute. Near salt water, guidance recommends hot-dip galvanized or stainless fasteners.

Driving nails

Nails should be driven straight with the head flush with the shingle surface. Overdriven nails cut into the mat and lose holding power; underdriven nails hold the next course up and can break through it. Pneumatic nailers are commonly run at about 90 to 110 psi and adjusted for the deck.