★ CONSTRUCTION · ROOFING · NAIL CHART
20 squares of 3-tab shingles needs 6,400 nails — one 7,200-nail box, 45.71 lb. The nail length for every application, the count per square, and a calculator for total nails, boxes and weight. This one is the ROOFING-NAIL chart — which nail and how many — the nail-size-chart page is the NAIL-SIZE chart — penny sizes, lengths and gauges for nails generally — not roofing counts; the shingle-coverage-chart page is the SHINGLE-COVERAGE chart — how many shingles a roof takes — not how many nails; and the roof-pitch-chart page is the ROOF-PITCH chart — angle, slope and rafter length — not fasteners.
Pick the nailing pattern and enter the squares: 20 squares at 320 nails per square is 6,400 nails, one box of 7,200, 45.71 lb. The table gives the nail length for every application — 1-1/4 in on a new roof, 1-3/4 in on a re-roof — from GAF's application instructions.
6,400 nails. A square is 100 sq ft of roof, and a 3-tab shingle roof takes 80 shingles a square at 4 nails each — 320 nails a square. Twenty squares is 6,400 nails, which fits in one 7,200-nail box of coil nails, and the nails weigh 45.71 lb at 140 to the pound. That is the whole calculation: squares times nails per square, then divide by the box count and by the nails per pound. The table above gives the nail length and the count for each application, so the same arithmetic works for any of them: 20 squares of architectural shingles is 5,120 nails, 20 squares in a high-wind zone is 9,600 nails, and 25 squares of 3-tab is 8,000 nails.
| Application | Deck / layers | Nail length | Penny size | Gauge | Nails per shingle | Nails per square |
|---|---|---|---|---|---|---|
| 3-tab asphalt shingle, new roof | 3/8 in plywood | 1-1/4 in | 3d | 10–12 | 4 | 320 |
| 3-tab asphalt shingle, new roof | 1/2 in plywood or OSB | 1-1/4 in | 3d | 10–12 | 4 | 320 |
| Architectural asphalt shingle, new roof | 1/2 in plywood or OSB | 1-1/2 in | 4d | 10–12 | 4 | 256 |
| Asphalt shingle, re-roof over one layer | existing shingle + deck | 1-3/4 in | 5d | 10–12 | 4 | 320 |
| Asphalt shingle, high-wind zone | 1/2 in plywood or OSB | 1-1/4 in | 3d | 10–12, ring shank | 6 | 480 |
| Ridge and hip cap shingles | over field shingles | 1-3/4 in | 5d | 10–12 | 2 | — |
Lengths and the 3/4 in penetration rule: GAF application instructions for asphalt shingles — fasteners must be long enough to penetrate at least 3/4 in (19 mm) into wood decks or just through plywood decks, and must be driven flush with the shingle. Nails are zinc-coated steel or aluminum, 10-12 gauge, with heads 3/8 in to 7/16 in. Nail counts: a square is 100 sq ft; 3-tab shingles are 80 per square at a 5 in exposure, architectural shingles are 64 per square — the wrapper is the final word. Penny sizes: 1-1/4 in is 3d, 1-1/2 in is 4d, 1-3/4 in is 5d, 2 in is 6d. Ridge and hip cap shingles take 2 nails each and about a half inch more length than the field nails, because they sit over more layers. Wood shakes take 1-3/4 in to 2 in nails, 2 per shake; slate takes 1-1/2 in to 2 in stainless steel or copper nails.
The nail must reach the deck. GAF requires the fastener to penetrate at least 3/4 in into a wood deck or just through a plywood deck — a 1-1/4 in nail on a 1/2 in deck with a shingle and underlayment does that, with the tip just showing below. On a re-roof over one layer of shingles, the same 1-1/4 in nail stops in the old shingle and never reaches the deck, so the length goes to 1-3/4 in. A nail that is too short does not just hold less — it can void the shingle's wind rating and warranty. Add up the layers: shingle (1/8 in) + underlayment (1/16 in) + deck (1/2 in) is 11/16 in, and the nail must clear that plus 3/4 in of deck.
Four nails is the minimum, six is the wind rating. Four nails a shingle is the standard pattern and gives 320 nails a square on 3-tab shingles; six nails a shingle is the high-wind pattern and gives 480. The extra two nails are not optional where the code or the manufacturer requires them — they are what holds the shingle in a storm, and the box count jumps with them: one 7,200-nail box covers 22.50 squares at four nails a shingle but only 15 squares at six. Count the pattern your roof actually needs, not the pattern on the cheapest bid.
Buy by the box, check by the pound. Coil nails come 7,200 to a box (60 coils of 120), and loose nails are sold by weight — about 140 nails to the pound for 1-1/4 in 10-gauge nails, 199 for 11-gauge and 255 for 12-gauge, so the same box weighs very differently by gauge. A square of shingles takes about 2-1/4 lb of nails at four a shingle and about 3-1/2 lb at six. Order one box more than the count says: hips, ridges, valleys and starter courses all take extra nails, and a half-empty box is cheaper than a second trip.
On the defaults: 20 squares, 3-tab shingles, 4 nails each.
And the other way: one box of nails covers 22.50 squares at 320 a square; for 6,400 nails to weigh 45.71 lb the count is 140.01 nails per pound; and for 20 squares to need 6,400 nails the pattern is 320 nails per square.
The defaults are 20 squares of 3-tab asphalt shingles — a 2,000 sq ft roof — at 4 nails a shingle, 320 nails a square, in 7,200-nail boxes of 1-1/4 in coil nails at about 140 nails to the pound. The nail lengths are the GAF application-instruction figures for asphalt shingles on wood and plywood decks; the counts are 80 three-tab shingles a square at a 5 in exposure and 64 architectural shingles a square, both at 4 nails a shingle, and 6 nails a shingle in high-wind zones. The calculator does not add waste: hips, ridges, valleys, starter courses and cut shingles all take extra nails, so add a box or about 10% for a cut-up roof. The weights are planning figures — the count per pound depends on the gauge, and a 10-gauge nail weighs more than a 12-gauge one. Check the shingle wrapper and your local code before you order: the wrapper is the final word on the count, and the code is the final word on the length.
These notes repeat in every explainer section because this page is built to be read start to finish: the nail must reach the deck; four nails is the minimum, six is the wind rating; and buy by the box, check by the pound.
| Output | Formula | What it means |
|---|---|---|
| Total nails | squares × nails per square | 6,400.00 nails — 20 × 320. |
| Boxes | total nails ÷ nails per box, rounded up | 1 box — 6,400 ÷ 7,200, rounded up. |
| Weight | total nails ÷ nails per pound | 45.71 lb — 6,400 ÷ 140. |
| Nails per square | shingles per square × nails per shingle | 320 nails — 80 shingles × 4 nails. |
| Squares per box | nails per box ÷ nails per square | 22.50 squares — 7,200 ÷ 320. |
| Reverse: Squares covered by one box of nails | step | 22.50 squares: 22.50 squares at 320 nails per square is 7,200.00 nails — 1 box of 7200 and 51.43 lb at 140 nails to the pound.. |
| Reverse: Nails per pound for 6,400 nails to weigh 45.71 lb | step | 140.01 nails per pound: 20 squares at 320 nails per square is 6,400.00 nails — 1 box of 7200 and 45.71 lb at 140.01 nails to the pound.. |
| Reverse: Nails per square for 20 squares to need 6,400 nails | step | 320 nails per square: 20 squares at 320 nails per square is 6,400.00 nails — 1 box of 7200 and 45.71 lb at 140 nails to the pound.. |
| 25 squares of 3-tab shingles | same model | 25 squares at 320 nails per square is 8,000.00 nails — 2 boxes of 7200 and 57.14 lb at 140 nails to the pound.. |
| 20 squares of architectural shingles | same model | 20 squares at 256 nails per square is 5,120.00 nails — 1 box of 7200 and 36.57 lb at 140 nails to the pound.. |
| 20 squares in a high-wind zone (6 nails) | same model | 20 squares at 480 nails per square is 9,600.00 nails — 2 boxes of 7200 and 68.57 lb at 140 nails to the pound.. |
| 30 squares of 3-tab shingles | same model | 30 squares at 320 nails per square is 9,600.00 nails — 2 boxes of 7200 and 68.57 lb at 140 nails to the pound.. |
| 10 squares of 3-tab shingles | same model | 10 squares at 320 nails per square is 3,200.00 nails — 1 box of 7200 and 22.86 lb at 140 nails to the pound.. |
| 15 squares of architectural shingles | same model | 15 squares at 256 nails per square is 3,840.00 nails — 1 box of 7200 and 27.43 lb at 140 nails to the pound.. |
| 0 squares | same model | 0 squares at 320 nails per square is 0.00 nails — 0 boxes of 7200 and 0.00 lb at 140 nails to the pound.. |
| 1 square | same model | 1 squares at 320 nails per square is 320.00 nails — 1 box of 7200 and 2.29 lb at 140 nails to the pound.. |
| 100 squares | same model | 100 squares at 320 nails per square is 32,000.00 nails — 5 boxes of 7200 and 228.57 lb at 140 nails to the pound.. |
| 200 squares | same model | 200 squares at 320 nails per square is 64,000.00 nails — 9 boxes of 7200 and 457.14 lb at 140 nails to the pound.. |
Figures are the model's own totals on the numbers you type, computed from unrounded values: the total is the squares times the nails per square, the boxes are the total divided by the nails per box and rounded up, and the weight is the total divided by the nails per pound — the displayed weight is rounded to 2dp. The nail lengths and the 3/4 in penetration rule are GAF's application instructions for asphalt shingles; the counts are 80 three-tab shingles a square at a 5 in exposure and 64 architectural shingles a square, and the box count is 7,200 coil nails (60 coils of 120). The nails-per-pound figure is a planning figure — about 140 for 1-1/4 in 10-gauge nails (manufacturer technical data: 139), 199 for 11-gauge and 255 for 12-gauge — so the weight moves with the gauge. The calculator does not add waste for hips, ridges, valleys or starter courses, and it does not cover metal roofing, tile or slate fastening beyond the lengths noted. This page is a planning estimate, not a roofing specification: follow the shingle manufacturer's instructions and your local building code.
20 squares of 3-tab asphalt shingles at 320 nails per square needs 6,400 nails — 1 box of 7,200 coil nails, 45.71 lb at 140 nails to the pound. GAF requires 10-12 gauge nails with 3/8 in to 7/16 in heads, long enough to penetrate at least 3/4 in into wood decks or just through plywood decks. Source: Bright Side Kit, brightoolbox.com.
320 for 3-tab shingles at 4 nails each, 256 for architectural shingles, and 480 in a high-wind zone at 6 nails each. A square is 100 sq ft; 3-tab shingles are 80 per square.
1-1/4 in nails for a new asphalt shingle roof on 3/8 in to 1/2 in plywood; 1-1/2 in for architectural shingles; 1-3/4 in for a re-roof over one layer. The nail must penetrate at least 3/4 in into the deck.
6,400 nails — one 7,200-nail box, weighing 45.71 lb. That is 20 squares at 320 nails a square.
25 squares at 4 nails a shingle and 15 squares at 6 nails a shingle. A box holds 7,200 coil nails.
About 140 for 1-1/4 in 10-gauge nails — 199 for 11-gauge and 255 for 12-gauge. A square of shingles takes about 2-1/4 lb of nails at four a shingle.
Four nails is the standard pattern; six nails is the high-wind pattern. Ridge and hip cap shingles take 2 nails each.
They must penetrate at least 3/4 in into a wood deck, or just through a plywood deck — GAF's rule. A nail that stops in an old shingle layer does not hold.
10-12 gauge, with heads 3/8 in to 7/16 in — zinc-coated steel or aluminum. Ring shank nails hold better in high wind; stainless steel is for coastal roofs.