The number of roofing nails per square is about 250 to 320 for standard asphalt shingles installed with four nails each.
One roofing square covers 100 square feet of roof area. The exact nail count depends on the shingle product, since manufacturers use different numbers of shingles per square.
Roofing Nails Per Square at a Glance
| Shingle example | Shingles per square | Standard nails per shingle | Nails per square |
|---|---|---|---|
| Typical architectural shingles | About 64 | 4 | About 256 |
| GAF Timberline NS architectural shingles | 64 | 4 | 256 |
| GAF Royal Sovereign 3-tab shingles | 79 | 4 | 316 |
| High-wind installation | Product-dependent | 6 | About 384 to 474 |
GAF lists 256 nails per square for Timberline NS shingles and 316 nails per square for Royal Sovereign 3-tab shingles.
How to Calculate Roofing Nails Per Square
Use this formula:
Shingles per square × nails per shingle = nails per square
Examples:
- 64 shingles × 4 nails = 256 nails per square
- 79 shingles × 4 nails = 316 nails per square
- 64 shingles × 6 nails = 384 nails per square
- 79 shingles × 6 nails = 474 nails per square
The common estimate of 320 nails per square comes from a three-tab installation with about 80 shingles and four nails per shingle.
How Many Nails Are Needed for a Complete Roof?
Multiply the nail count per square by the number of squares on the roof.
For a 20-square roof:
- Architectural shingles at 256 nails per square: 5,120 field-shingle nails
- 3-tab shingles at about 320 nails per square: about 6,400 field-shingle nails
- Six-nail architectural installation at 384 nails per square: 7,680 field-shingle nails
These totals cover the main field shingles. Starter shingles, ridge caps, hip shingles and other roofing components need additional fasteners.
When Are Six Nails Per Shingle Required?
A six-nail pattern may apply to:
- High-wind warranty coverage
- Certain local building codes
- Steep-slope or mansard roofs
- Some shingle products
- Coastal or other high-wind regions
GAF installation instructions identify six nails as a required pattern for some local codes and certain wind-coverage options. Owens Corning also specifies six fasteners for some steep-slope applications and maximum wind-warranty installations.
Do not use six nails automatically. Check the installation instructions on the shingle wrapper and confirm the local code requirements.
What Is the Best Number to Use for Estimating?
For a quick estimate:
- Use 320 nails per square for many standard 3-tab installations.
- Use 256 nails per square for many architectural shingles with 64 pieces per square.
- Use the manufacturer's nail count when it is available.
- Add fasteners for starter strips, ridge caps and hip caps.
The product specification is the most reliable source because shingle size and pieces per square vary. GAF lists three bundles per square for several common asphalt shingle products, but the number of pieces and required nails still differs by product design.
For most asphalt shingle roofs, start with the product's stated nail count. If that information is unavailable, 256 to 320 field-shingle nails per square is a reasonable estimate for a four-nail installation. Use a higher count only when the product instructions or local requirements call for six nails.