How Many Bundles of Shingles Do You Need for a Shed Roof?
A 10 by 12 foot shed takes about 5 bundles of shingles at the usual three bundles to a square, or 7 if the shingles are the heavier four-bundle kind, plus one bundle of ridge cap if the roof has a ridge. Larger sheds scale from there, and the table below covers four common sizes.
That is lower than many online estimates, because a shed roof is small. A 10 by 12 shed has about 150 square feet of roof, and a bundle covers about 33 square feet.
The formula
Bundles = roof area × 1.10 for waste ÷ 100 × bundles per square, rounded up. Four things to find, in this order:
- The roof area, including the overhang and the slope.
- A waste allowance. Use 10 percent for a plain roof and 15 percent if it is your first roof or the shape is cut up.
- The area in squares (one square is 100 square feet).
- Bundles per square, which is printed on the wrapper.
Step 1: The roof area of a shed
A shed roof covers the footprint plus the overhang, stretched by the slope. Multiply the length by the depth, both measured out to the edge of the overhang, then by the pitch factor below.
A gable and a single-slope roof over the same footprint have the same area: two sloping halves add up to one slope across the full depth. The ridge is what differs, because only the gable needs ridge cap.
| Pitch | 2 in 12 | 3 in 12 | 4 in 12 | 6 in 12 | 8 in 12 |
|---|---|---|---|---|---|
| Multiply the footprint by | 1.014 | 1.031 | 1.054 | 1.118 | 1.202 |
The shed roof calculator does this from your dimensions, and the roof size calculator works from the floor area of the building.
Bundles per square
Most shingles come three bundles to a square, which makes a bundle about 33 square feet. Some heavier laminated shingles come four to a square, which makes a bundle 25 square feet. The wrapper states the coverage, and it is the number to use, since the same brand can sell both weights.
Bundles by shed size
Assumptions: a 6-inch overhang on every side, a 4 in 12 pitch and 10 percent waste.
| Shed | Roof area with waste | Squares | Bundles at 3 per square | Bundles at 4 per square |
|---|---|---|---|---|
| 8 × 10 ft | 115 sq ft | 1.15 | 4 | 5 |
| 10 × 12 ft | 166 sq ft | 1.66 | 5 | 7 |
| 12 × 16 ft | 256 sq ft | 2.56 | 8 | 11 |
| 12 × 20 ft | 317 sq ft | 3.17 | 10 | 13 |
Pitch moves the numbers modestly. At 6 in 12 the same 10 × 12 shed grows to about 176 square feet with waste and takes 6 bundles at three to a square.
The other bundles: starter and ridge
Starter strip runs along the eaves, and ideally the rakes. A single bundle usually covers more than 100 linear feet, so one is enough for any shed, or you can cut tabs off ordinary shingles to make starter pieces.
Ridge cap is sold by the bundle at roughly 20 to 35 linear feet depending on the product. A single-slope shed has no ridge. A gable shed under about 20 feet long needs one bundle.
The shingle bundle calculator adds underlayment, drip edge and nails to the list, and the drip edge calculator counts the pieces.
Worked example: a 10 × 12 gable shed at 4 in 12
- Footprint with a 6-inch overhang: 11 × 13 = 143 sq ft.
- Pitch factor 1.054: 143 × 1.054 = 150.7 sq ft of roof.
- With 10 percent waste: 165.8 sq ft, or 1.66 squares.
- At three bundles per square: 4.97, which rounds up to 5 bundles.
- Ridge cap: 1 bundle. Starter strip: 1 bundle.
- Drip edge: two eaves at 13 ft is 26 ft, and four rakes at about 5.8 ft is 23.2 ft, so 49.2 ft or five 10-foot pieces.
Because 4.97 rounds to exactly 5, buy a sixth bundle. A spare is cheap next to a second trip, and the shingles will match.
More shed roof guides
- How to install asphalt shingles on a shed roof
- How to shingle a lean-to shed roof
- How to shingle a gambrel shed roof
- How to finish the last row of shingles on a shed roof
- How to install a metal roof on a shed
- How to install rolled roofing
- How to install a rubber (EPDM) roof
- Minimum roof pitch for a shed, by material
- Best roofing for a shed: shingles, metal, roll roofing or EPDM
Working out quantities and pitch? The shed roof calculator, shingle bundle calculator and drip edge calculator do the arithmetic.
Conclusion
Working out the bundles of shingles for a shed roof takes four lines of arithmetic: area, waste, squares, bundles. Add one bundle of ridge cap for a gable and one of starter, and round every figure up.
There is also a quick sanity check. A shed roof is only a little bigger than the shed’s floor, so an estimate of ten or more bundles for a 10 × 12 shed probably counts each slope as if it were the whole footprint. For the installation itself, see how to install asphalt shingles on a shed roof.
