About 264 for architectural shingles on a four-nail pattern and 320 for three-tab, because architectural shingles are larger and there are fewer per square. Six-nail high-wind patterns are 396 and 480. That is roughly two pounds of 1¼ inch nails per square.
Quick answer: a roofing square = 100 sq ft of roof. Standard 4-nail pattern uses 320 nails per square; 6-nail high-wind uses 480 per square; 8-nail Florida HVHZ uses 640 per square. The mini calculator below converts roof squares → nail count, weight (lbs), and box count instantly.
Nails per square follows from the shingle count, not the area directly. Architectural shingles run about 66 to the square and three-tab about 80, and each shingle takes four nails as standard or six in a high-wind zone.
| Shingle type | Shingles per square | 4-nail pattern | 6-nail high-wind |
|---|---|---|---|
| Architectural | 66 | 264 | 396 |
| Three-tab | 80 | 320 | 480 |
The commonly quoted "320 nails per square" is the three-tab four-nail figure. Architectural shingles are larger, so there are fewer of them and the count is lower.
| Roof area | 4-nail pattern | Weight | 6-nail high-wind | Weight |
|---|---|---|---|---|
| 1,000 sq ft | 2,640 | 18.9 lb | 3,960 | 28.3 lb |
| 1,500 sq ft | 3,960 | 28.3 lb | 5,940 | 42.4 lb |
| 2,000 sq ft | 5,280 | 37.7 lb | 7,920 | 56.6 lb |
| 2,500 sq ft | 6,600 | 47.1 lb | 9,900 | 70.7 lb |
| 3,000 sq ft | 7,920 | 56.6 lb | 11,880 | 84.9 lb |
Guns misfire, coils jam, and the last course always eats more than the arithmetic says. Roofing nails keep indefinitely in a dry box, so the surplus is not wasted money — whereas running out on the last afternoon costs a trip and the rest of the day.
About 264 for architectural shingles on a four-nail pattern and 320 for three-tab, because architectural shingles are larger and there are fewer of them per square. Six-nail high-wind patterns raise both by half.
Roughly two pounds per square on a four-nail pattern with 1¼ inch nails, at about 140 nails to the pound. Longer nails weigh more each, so the figure rises with length.
That is the three-tab four-nail figure, at 80 shingles per square. Architectural shingles run about 66 per square, so the same pattern gives a lower count.
About 10% over. Guns misfire, coils jam and the last course always eats more than expected. Roofing nails keep indefinitely in a dry box, so the surplus is not wasted money.