About this example roofing estimate
The example prices a 24-square tear-off and replacement: one layer removed, 26 squares of architectural shingles (about 8% waste), synthetic underlayment, 180 ft of drip edge, a dumpster, and labor per square. Ice and water shield for the eaves and valleys is an optional section the homeowner can add when they accept.
How to estimate a roofing job
Roofing is priced in squares. One square covers 100 sq ft of roof. Measure the footprint, multiply by the pitch factor below, divide by 100, then add 10% waste for a simple gable roof or 15% for hips and valleys.
| Pitch | Multiply footprint by |
|---|---|
| 4/12 | 1.054 |
| 6/12 | 1.118 |
| 8/12 | 1.202 |
| 10/12 | 1.302 |
| 12/12 | 1.414 |
What goes on a roofing estimate
- Tear-off per layer, per square
- Shingles, per square, with waste
- Underlayment, ice and water shield, drip edge, starter and ridge cap
- Dumpster and disposal
- Permit
- Labor per square, with a steep-pitch charge if needed
Questions
How many bundles are in a square?
Most architectural shingles come 3 bundles to a square. Check the wrapper, because some heavy shingles are 4 or 5.
Should a roofing estimate include decking replacement?
List it as an optional line priced per sheet. You can't know how much rotten decking there is until the tear-off.