From the street, two new roofs can look almost the same. The difference between one that lasts 25 years and one that leaks in three usually comes down to details you never see once the shingles are on. Here is what our roofing judges look for, and what you can check as a homeowner.
1. The decking was inspected and repaired
After the old roof comes off, a good crew walks the bare decking and replaces any soft, rotted, or delaminated sheets. Ask your contractor how they price decking repairs before the job starts, and ask for photos of the bare roof. A contractor who shingles over bad decking is hiding a problem, not solving it.
2. Underlayment and ice and water shield are in the right places
Synthetic underlayment should cover the whole deck. Self-adhering ice and water shield belongs in valleys, around penetrations, and along the eaves in colder climates. Your local building code sets the minimum, and many manufacturers require more for their warranty.
3. Flashing was replaced, not reused
Leaks almost always start where the roof meets something else: a chimney, a wall, a skylight, or a vent pipe. Good flashing work means new step flashing along walls, counter flashing at chimneys, and new pipe boots. Reusing old, bent flashing to save time is one of the most common shortcuts.
4. Ventilation is balanced
A roof needs air coming in low (soffit vents) and going out high (ridge or box vents). Too little ventilation cooks shingles from below and can cause moisture problems in the attic. A good roofer will look at your attic, not just the roof surface, and explain the plan.
5. The fastening is right
Shingles have a specific nailing zone, and high-wind areas need more nails per shingle. Nails driven too high, too low, or crooked can let shingles blow off. This is hard for a homeowner to check after the fact, which is why during-the-job photos matter.
6. The lines are straight and the details are tidy
Look at the finished roof from the yard. Courses should run straight, ridge caps should be even, and valleys should be clean. Sloppy visible work is often a sign of sloppy hidden work.
7. The site was left clean
A good crew runs a magnet over the lawn and driveway to pick up nails, protects landscaping, and hauls away all debris. Ask how they handle cleanup before you sign.
What to ask for before the job starts
- Photos of the bare decking and of any repairs
- The brand and product line of shingles, underlayment, and ice and water shield
- Whether flashing and pipe boots will be replaced
- How ventilation will be handled
- Proof of license (where required) and insurance
- The manufacturer warranty the job qualifies for
These are the same things our roofing judges score when a contractor enters a job for the Built Right Award. If a roofer shows you a Built Right badge, you can check its ID and see the winning project.