What Size Roofing Nails Do I Need?
Updated April 2026 · 4 min read
Pick the wrong nail length and one of two things happens: the nail blows through the deck and pokes out the underside, or it doesn't penetrate enough and the shingle lifts in the next windstorm. Neither is a callback you want.
The rule code actually requires
Most building codes require that roofing nails penetrate at least 3/4" into the deck, or all the way through if the deck is thinner than 3/4". That's the part that matters. The rest of the length is just covering the shingle layers above.
Asphalt shingles by deck thickness
- 1" nails: Single layer of shingles on a 1/2" or 5/8" deck. The most common pick for new construction with thin shingles.
- 1-1/4" nails: The default for most residential re-roofs. Works for a single layer over architectural shingles or new install on 5/8" deck.
- 1-1/2" nails: Use for thick architectural shingles, or when you're going over an existing layer (where allowed by code).
- 1-3/4" nails: Two layers of shingles, or thick laminated shingles on thicker decks.
- 2" nails: Specialty applications — multiple layers, very thick decks, or tile starter strips.
Underlayment and cap nails
For felt and synthetic underlayment, code typically calls for plastic-cap nails with a 1" cap and a 1" to 1-1/4" shank. The cap prevents tear-through under wind load. Don't substitute regular roofing nails for underlayment — most building inspectors will flag it.
Material: galvanized vs stainless
Hot-dipped galvanized is the standard for most asphalt shingle work and what comes in nearly every coil. Stainless costs more but is required (or strongly recommended) within a few miles of saltwater coastlines, on cedar shake roofs, and under copper flashing. Aluminum nails exist but corrode in contact with treated wood — skip them.
Gauge and head size
Standard roofing nails are 11 or 12 gauge with a 3/8" to 7/16" diameter head. Manufacturer warranties on shingles almost always require a minimum 3/8" head — undersized nails void coverage. When in doubt, check the shingle wrapper for the spec.