Planning result
For 1,200 sq ft of measured roof area, 10% waste gives 1,320 sq ft, or 13.2 roofing squares. At 3 bundles per square, plan about 40 field-shingle bundles before separate accessories.
Assumptions
| Measured roof area | 1,200 sq ft after pitch and roof planes are accounted for. |
|---|---|
| Waste | 10% for a simpler roof. |
| Bundle rate | 3 bundles per roofing square. |
| Accessories | Starter, ridge, vents, flashing, and underlayment are separate. |
Calculation
| Step | Result | Formula |
|---|---|---|
| Measured roof area | 1,200 sq ft | Given roof surface area |
| Waste-adjusted area | 1,320 sq ft | 1,200 x 1.10 |
| Roofing squares | 13.2 squares | 1,320 / 100 |
| Bundles | 39.6 bundles | 13.2 x 3 |
| Practical buy | 40 bundles | Round up to full bundles |
Use actual roof area
This example starts from measured roof surface area, not house floor area. Pitch, overhangs, garages, and roof shape can change the number.
Do not hide accessories in waste
Ridge caps, starter shingles, flashing, vents, and underlayment should be counted as separate line items.
Next step
Use the linked calculator or planning hub to adjust dimensions, waste, coverage, depth, spacing, or product packaging for the real project.
Related guides
FAQ
How many bundles for 1,200 sq ft of roof?
With 10% waste and 3 bundles per square, plan about 40 field-shingle bundles.
Does this include ridge caps?
No. Ridge caps are estimated separately.
Can I use house square footage?
Only as a rough starting point. Roof surface area is more accurate.