Hiring the wrong roofing contractor is one of the most expensive mistakes a San Diego homeowner or property owner can make. Poor installation leads to leaks, voided warranties, and in some cases structural damage that costs far more to fix than the original roof would have.
This guide gives you a straightforward process for evaluating roofing contractors — what to check, what to ask, and what to watch out for.
Start with California Licensing
Every roofing contractor in California must hold a C-39 Roofing Contractor license for any job where the total price (labor and materials) exceeds $500. This is not optional — it's state law.
The C-39 license requires:
- Passing a trade knowledge exam
- Proving 4 years of journeyman-level experience (or equivalent)
- Maintaining a contractor bond
- Carrying workers' compensation insurance for employees
Verify any contractor's license at cslb.ca.gov before you talk to them about your project. Enter the license number or company name. You'll see whether the license is current, what classification it covers, and whether there are any disciplinary actions on file.
Do not hire an unlicensed roofer. Beyond the quality risk, if an unlicensed contractor is injured on your property, you can be liable. And unlicensed work voids most homeowners' insurance coverage for related damage.
Verify Insurance — Not Just Their Word
Ask for certificates of insurance directly from the contractor's insurer, not a copy the contractor hands you. Certificates can be forged. Call the insurance company to verify the policy is active if you have any doubt.
Two policies matter:
General liability insurance (minimum $1 million per occurrence) covers damage to your property caused by the contractor's work or workers. If a crew member drops a ladder through your skylight, this pays for it.
Workers' compensation insurance covers injuries to the contractor's employees while working on your property. Without it, you're potentially liable for a worker's medical bills and lost wages if they're injured on your roof.
Ask to be named as an additional insured on the general liability certificate. This is standard practice and any reputable contractor will accommodate it.
Manufacturer Certifications Tell You About Quality Standards
State licensing establishes a minimum bar. Manufacturer certifications tell you about ongoing training and quality commitment.
GAF Master Elite is the gold standard for shingle roofing. GAF awards this certification to the top 3% of contractors nationally based on training completion, licensing, insurance standards, and reputation checks. There are fewer than 2,500 GAF Master Elite contractors in the entire US.
Practical reason this matters: Only GAF Master Elite contractors can offer the Golden Pledge and System Plus warranty (up to 50 years, covering both materials and labor). A standard contractor can only offer the basic manufacturer warranty on shingles with no labor coverage after 2 years. If your roof fails in year 8, the warranty difference is enormous.
Owens Corning Platinum Preferred and CertainTeed SELECT ShingleMaster are equivalent tier-1 programs from other major manufacturers. Any of these certifications indicates a contractor who has invested in meeting meaningful standards.
For tile or metal roofing, ask about manufacturer training. GAF, Boral, and Decra all offer installation certification programs.
Check Reviews Across Multiple Platforms
No single review platform is reliable on its own. A contractor with 200 Google reviews and 4 reviews on Yelp (or vice versa) warrants a closer look. Concentrated reviews on one platform can indicate review management rather than a genuine service history.
Look at Google, Yelp, and BBB together. For each platform:
Read the negatives carefully. How the contractor responds to negative reviews tells you more than the review itself. Professional, solution-focused responses to criticism indicate a company that cares about reputation. Defensive, dismissive responses are a warning sign.
Look for review authenticity signals. Detailed reviews mentioning specific project details, crew names, and timelines are more credible than generic "great service, highly recommend!" reviews. Look for reviews with project photos.
Check the review timeline. A company with 50 reviews from 5 years ago and 10 reviews from the last year may have quality problems. Consistent review velocity over time indicates consistent service delivery.
Evaluate the Written Estimate
The estimate is where many contractors reveal themselves. A professional written estimate should include:
Material specifications: Not just "shingles" — specific brand, product line, and color. GAF Timberline HDZ in Charcoal, not just "architectural shingles." This lets you verify what's being installed and compare quotes accurately.
Underlayment specification: What type? Synthetic or felt? What weight or grade? Underlayment is the most important waterproofing layer on the roof and one of the easiest places to cut costs invisibly.
Deck replacement pricing: How much per 4x8 sheet if damaged decking is found during tear-off? This should be in writing before work starts, not a conversation after the old roof is off.
Permit line item: Roof replacement requires permits in San Diego. The permit fee should be visible in the estimate. A contractor who says permits aren't needed for a full replacement either doesn't know the code or plans to skip them.
Cleanup description: What does the cleanup process include? Magnetic sweeping for nails? Tarping of landscaping? Dumpster placement and removal? Vague estimates on cleanup often mean inadequate cleanup.
Payment schedule: Standard practice is 10 to 30% deposit at signing, progress payments tied to milestones (tear-off complete, new material on), and final payment at completion. Be cautious of contractors requesting more than 50% upfront.
Questions to Ask Every Contractor
Use these questions to evaluate each contractor you interview:
- Will your own employees be on my roof, or will you subcontract?
- Who is the foreman on this job and how long have they worked for you?
- What shingles are you recommending and why this product vs. alternatives?
- What tier of manufacturer warranty can you offer?
- What happens if damaged decking is found after tear-off?
- Will you pull all required permits, and can I see the permit before work starts?
- What does your cleanup process include, specifically?
- Can you give me three references from roofing projects in the last 6 months that I can call?
Any qualified contractor should answer all of these questions directly and comfortably. Evasiveness on any of them is a meaningful signal.
Commercial vs. Residential: Different Considerations
If you're evaluating contractors for a commercial property — office building, retail, multi-family, or industrial — add these questions:
- Do you carry commercial general liability at higher limits (typically $2M+)?
- What experience do you have with the specific roofing system on my building (TPO, EPDM, modified bitumen, built-up)?
- Can you provide references from similar commercial projects in San Diego County?
- How do you minimize disruption to tenants or business operations during work?
Commercial roofing requires different skills and equipment than residential. Verify the contractor has genuine commercial experience, not just residential crews taking on commercial jobs.
Red Flags to Walk Away From
Extremely low bids. If one quote is $4,000 to $5,000 lower than others for the same scope, something is being cut. It's usually underlayment grade, shingle quality, or the crew's qualifications. Price should be competitive, not dramatically below market.
No physical San Diego location. After atmospheric river events, out-of-state contractors appear throughout San Diego neighborhoods. Verify the contractor has a real local presence — not just a P.O. box or address that maps to a UPS Store.
Pressure to sign immediately. Any contractor who needs your signature today before you can "get the discount" is using a pressure tactic, not running a business.
Cash-only pricing. Some contractors offer significant discounts for cash payment. This often indicates unreported labor, unlicensed workers, or a desire to avoid a paper trail.
No permit discussion. Full roof replacement in San Diego requires permits regardless of roof type or size. A contractor who doesn't mention permits in their process either doesn't pull them or doesn't know they're required.
Peak Builders San Diego
Peak Builders has been roofing and remodeling San Diego properties since 1999. We're GAF Master Elite certified, California C-39 licensed, BBB A+ accredited, and fully insured. Our roofing crews are employees — not subcontractors.
We serve La Jolla, Carlsbad, Oceanside, Chula Vista, Escondido, Poway, El Cajon, Encinitas, Rancho Bernardo, and all of San Diego County.
Call (619) 330-8185 for a free roof inspection and written estimate. No pressure, no obligation.
