How Many Shingles for a 1,200 Square Foot House?
Roofing squares needed
14.8 squares
A 1,200 square foot footprint, 40 by 30, at a 6/12 pitch with ten percent waste.
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How that number is worked out
These are the figures this page was built with and every line the calculator produces from them. Change anything above and all of it moves.
- Building length40 ft
- Building width30 ft
- Roof pitch, rise per 12 in6 /12
- Waste allowance10 %
- Ridge length, 0 if unknown40 ft
Roofing squares needed14.8 squares
| Footprint area | 1,200 sq ft |
|---|---|
| Slope multiplier at 6/12 | 1.12 x |
| Actual roof surface | 1,342 sq ft |
| Squares before waste | 13.4 |
| Squares with 10% waste | 14.8order to this number |
The material list this produces
| Shingles, bundles (3 per square) | 45 |
|---|---|
| Synthetic underlayment, rolls (10 sq each) | 2 |
| Starter strip, linear ft | 168 |
| Ridge cap, linear ft | 40 |
| Drip edge, linear ft | 140 |
| Roofing nails, lb | 33 |
Roof pitch compared
Pitch is the number most people guess at, and it is worth more shingles than any other input. Same house, five pitches.
| Roof pitch | Roofing squares needed |
|---|---|
| 4/12 | 13.9 squares |
| 6/12 | 14.8 squares |
| 8/12 | 15.9 squares |
| 10/12 | 17.2 squares |
| 12/12 | 18.7 squares |
What else matters here
Twelve hundred square feet at 6/12 gives 1,342 square feet of roof, just under fifteen squares. Shingles come three bundles to the square, so that is 45 bundles, which is fifteen squares worth of pallet space and about 3,500 pounds sitting on the roof if it is loaded rather than staged on the ground.
Loading a roof this size in one go is normal practice and is fine on sound framing, but spread the pallets along the ridge rather than stacking them in one place. Fifteen squares concentrated over two rafters is a real load, and old sheathing tells you about it later rather than at the time.
Underlayment at this size is two rolls of synthetic at ten squares each, with the second one barely opened. That leftover roll is worth keeping intact and sealed rather than half used and left in a truck, because it is the first thing you want on the next repair.
What this calculator assumes
- Footprint times the slope multiplier gives the actual roof surface. A 6/12 roof is 11.8 percent larger than the ground it covers, which is the number most people forget.
- Three bundles per square is standard for both three tab and architectural shingles. Check your brand, a few premium lines run four.
- Synthetic underlayment is figured at 10 squares per roll, starter and ridge cap at one linear foot per foot.
Questions people ask
How many bundles of shingles for a 1,200 sq ft house?
Around 45 bundles at a 6/12 pitch with ten percent waste. That is 14.8 squares of roof over a 1,200 square foot footprint.
How many squares is a 1,200 sq ft roof?
The footprint is 12 squares flat, but the roof over it is 13.4 at 6/12 before waste and 14.8 after. The steeper the pitch the further those numbers separate.
How much does it cost to reroof a 1,200 sq ft house?
Take the squares from this page and price them against your own material and labor rates. The job cost calculator on this site adds overhead and profit so the number you hand over is a price rather than a cost.
The roofing calculator takes any dimensions you like and hands back the same list.