Calculate how many roofing nails you need for asphalt shingles from your roof area, squares, or bundles, plus the pounds, coils, and boxes to buy.
Roofing Nail Formula
Start by turning the roof size into squares, since one roofing square covers 100 square feet:
Squares = Area / 100
Multiply the squares by the nails each shingle takes and the shingles in a square to get the field nails, then add a waste factor:
Nails = Squares * Nps * Sps * (1 + W / 100)
Convert the nail count into the pounds and the nailer coils you actually buy:
Pounds = Nails / Npp
Coils = Nails / Nc
Variables:
- Area is the sloped roof area in square feet, not the building footprint
- Squares is the roof area in roofing squares, where one square is 100 square feet
- Nps is the nails per shingle, usually 4 for standard nailing or 6 in high-wind zones
- Sps is the shingles per square, about 80 for 3-tab and about 64 for architectural shingles
- W is the waste factor as a percent, added for cutoffs, mistakes, and spares
- Npp is the nails per pound for the length you buy, about 156 for a 1-1/4 inch galvanized roofing nail
- Nc is the nails per coil, 120 for a standard pneumatic coil nailer
The size input sets the squares, so entering area, squares, or bundles all lead to the same nail count. The shingle type sets Sps and the nailing pattern sets Nps, and together they give the nails per square. The nail length sets Npp, which drives the weight, box, and cost lines. The coil line divides the total by 120 so you know how many nail coils to load, which most roofing nail tools leave out.
Nails Per Square, Pound, and Coil
The first table gives the field nails for one square at each common pattern, with the weight and coils for that square using a 1-1/4 inch nail. Multiply a row by your number of squares to size an order fast.
| Shingle and pattern | Nails per square | Pounds per square | Coils per square |
|---|---|---|---|
| 3-tab, 4 nails (standard) | 320 | 2.1 lb | 3 |
| 3-tab, 6 nails (high wind) | 480 | 3.1 lb | 4 |
| Architectural, 4 nails | 256 | 1.6 lb | 3 |
| Architectural, 6 nails (high wind) | 384 | 2.5 lb | 4 |
The coils column is the part most nail calculators skip. A pneumatic roofing nailer loads a 120-nail coil, so dividing the total by 120 tells you how many coils to buy and roughly how often you reload on the roof.
The second table shows how the nail length changes the nails per pound, which sets how heavy the order is and what length reaches the deck.
| Nail length | Approx. nails per pound | Common use |
|---|---|---|
| 1 in | 190 | Thin or overlay decking |
| 1-1/4 in | 156 | New shingles over bare 1/2 in deck, most common |
| 1-1/2 in | 133 | Thicker shingles or 3/4 in deck |
| 1-3/4 in | 116 | Nailing over one existing layer |
| 2 in | 103 | Thick assemblies or a second layover |
Counts are for smooth-shank galvanized roofing nails and are approximate, since gauge, coating, and brand all shift the weight. The count printed on the box is the number to trust for your order.
Example Problems
Example 1: Nails for a 2,000 square foot 3-tab roof.
The roof is 2,000 sq ft of 3-tab shingles nailed 4 per shingle with a 10 percent waste factor. Squares = 2000 / 100 = 20. Field nails = 20 * 80 * 4 = 6,400. With waste, Nails = 6,400 * 1.10 = 7,040. At 156 nails per pound that is 7,040 / 156 = 45.1 pounds, which rounds up to 10 five-pound boxes. In coils it is 7,040 / 120 = 59 coils.
Example 2: High-wind architectural roof by the square.
A 15-square architectural roof in a high-wind zone is nailed 6 per shingle with no added waste. Field nails = 15 * 64 * 6 = 5,760. With a 1-1/2 inch nail at 133 nails per pound that is 5,760 / 133 = 43.3 pounds. In coils it is 5,760 / 120 = 48 coils.
Frequently Asked Questions
How many roofing nails do I need per square?
For standard 3-tab shingles at 4 nails each, a square takes about 320 nails, since a square holds about 80 shingles. A 6-nail high-wind pattern raises that to 480. Architectural shingles cover a square with fewer, larger shingles, about 64, so they take about 256 nails at 4 per shingle and 384 at 6. Multiply the per-square figure by your number of squares, then add a waste factor for cutoffs and spares.
How many roofing nails are in a pound and in a coil?
A 1-1/4 inch galvanized roofing nail runs about 156 to the pound, so a 5-pound box holds roughly 780 nails. Longer nails weigh more and give fewer per pound, down to about 103 for a 2 inch nail. Pneumatic coil nailers use a wire coil of 120 nails, so a bulk box of 7,200 nails holds 60 coils. The exact count is printed on the box and varies with gauge and coating.
What length roofing nail should I use?
The nail has to pass through the shingles and any underlayment and then reach at least 3/4 inch into the deck, or all the way through thin decking. For new asphalt shingles over a single layer on a 1/2 inch deck, a 1-1/4 inch nail is the usual pick. Move up to 1-1/2 or 1-3/4 inch for thicker architectural shingles or when you nail over an existing layer. Check local code, since high-wind and coastal areas can require specific lengths or ring-shank nails.
