Hiring a roofer is one of the higher-stakes home-service decisions you'll make. The job is labor-intensive, the work sits above your head for decades, and a bad install shows up in leaks years later when the contractor has moved on. This guide skips the obvious advice ("get three quotes!") and focuses on the specific questions that separate good roofers from the rest.
1. Are you licensed in this state, and can I see the number?
Every state regulates contractors differently. In Delaware you need a general contractor license from the Division of Revenue; in Pennsylvania it's the Attorney General's HIC (Home Improvement Contractor) registration; in Maryland it's the MHIC license. A legitimate roofer will volunteer the number before you ask. If they hesitate or only reference "being insured," that's a red flag.
2. What's your liability insurance coverage and workers' comp?
Ask for a Certificate of Insurance (COI) sent directly from their insurer, not a copy they provide. Minimum you want: $1M general liability and active workers' comp. If a worker falls from your roof and the company lacks coverage, you can be sued directly. The COI takes the insurer 10 minutes to email; any contractor unwilling to provide one is saving themselves money at your legal expense.
3. Will this be written, fixed-price, with specified materials?
"We'll take care of you" is not a scope. Get a written estimate that includes: material brand and grade (GAF Timberline HDZ, not "architectural shingles"), number of layers removed, underlayment type, ice & water shield coverage, ridge vent details, nail type and count per shingle, cleanup, and dumpster rental. The difference between a cheap bid and an honest bid is usually in what's missing from the scope.
4. Who actually does the work?
Some roofing companies sell the job, then subcontract the install to a crew they've never worked with. That's not automatically bad, but you want to know. Ask: "Are these your W-2 employees, long-term subcontractor crews, or day labor?" A company that uses the same subcontractor crew for five years has a different quality floor than one shopping each job.
5. What's your warranty , and is it a manufacturer warranty or your own?
Manufacturer warranties (GAF, CertainTeed, Owens Corning) cover the shingles for 20-50 years but only if installed per spec. A "GAF Master Elite" certified installer can offer an enhanced manufacturer warranty that also covers labor. A company-provided warranty is only as good as the company , ask how long they've been in business and whether the warranty transfers if they close.
6. How do you handle unexpected decking replacement?
Once the old roof comes off, you may discover rotted plywood underneath. Ask ahead of time: "What's your per-sheet price for deck replacement?" A reputable roofer will quote $75-$120 per sheet installed. Someone who says "we'll figure it out when we see it" is positioning to charge whatever they want when your roof is already open.
7. Can I talk to two references from the past 6 months?
Not last year, not "some of our best jobs" , the last six months of actual customers. If they resist, ask why. The best roofers have customers happy to vouch for them.
8. How long will the job take, and what if it rains?
A typical residential reroof is 1-3 days. If your roofer says "a week" with no complications, they're running too many jobs at once. Ask about weather contingency: do they tarp every night, or can they complete phases weatherproof?
Red flags to walk away from
- "We can only do this price if you sign today" , legitimate roofers give 30+ days to decide
- Full payment up front , pros take deposit + progress payments
- Verbal-only estimates
- No physical business address you can visit
- Pressure to file a specific insurance claim their way
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