How to Choose a Commercial Roofing Contractor: 8 Questions to Ask

Hiring the wrong commercial roofing contractor is one of the most expensive mistakes a building owner can make. A poorly installed roof will fail prematurely, void manufacturer warranties, generate recurring leak problems, and ultimately require a costly replacement far sooner than it should. On the other hand, the right contractor will deliver a roof that protects your building for decades with minimal problems.

The challenge is that from the outside, commercial roofing contractors can look similar. They may use the same brand names, quote comparable prices, and promise excellent results. The differences between a genuinely qualified contractor and one that will cut corners only become apparent when you know the right questions to ask.

At Windward Roofing & Construction, we have been in business since 1984 and have earned our reputation through four decades of quality work. We know what separates reputable contractors from the rest because we compete alongside them every day. Here are eight critical questions that will help you evaluate any commercial roofing contractor you are considering.

1. Are You Properly Licensed and Registered?

This is the most basic qualification, yet it is surprising how many building owners fail to verify it. Commercial roofing contractors must hold the appropriate licenses for the jurisdictions where they work. In Illinois, roofing contractors must be registered with the state. In Chicago, additional licensing through the Department of Buildings is required. Florida has its own separate licensing requirements.

What to verify:

• State roofing contractor registration or license number
• City-specific licenses where applicable
• Current and active status (not expired, suspended, or revoked)
• The license is in the name of the company you are hiring, not a different entity

Red flags: A contractor who cannot readily provide license information, asks you to pull the building permit yourself, or suggests the project does not require a permit is not one you should trust with your building.

2. What Insurance Coverage Do You Carry?

Insurance is your protection against liability if something goes wrong during the project. A commercial roofing contractor should carry comprehensive insurance that protects both their workers and your property.

Required coverage:

• General liability insurance with minimum limits of $1 million per occurrence and $2 million aggregate. For larger projects, $5 million or more is appropriate.
• Workers' compensation insurance covering all employees working on your project. This is required by law in every state where we operate.
• Commercial auto insurance covering vehicles used in the course of the project.
• Umbrella or excess liability policy for additional coverage beyond the primary policy limits.

What to verify: Request a current certificate of insurance and confirm the policy dates cover your project timeline. Call the insurance carrier directly to verify the policy is active. Ask to be named as an additional insured on the general liability policy for the duration of the project, which is standard practice on commercial work.

Red flags: A contractor who is reluctant to provide insurance certificates, whose coverage has lapsed, or who carries only the minimum required limits may be cutting costs in ways that put you at risk.

3. How Long Have You Been in the Commercial Roofing Business?

Experience matters enormously in commercial roofing. The industry has a high turnover rate, with many contractors entering and exiting the market within a few years. A company that has been in business for a decade or more has demonstrated the ability to stand behind their work, manage projects effectively, and maintain financial stability through economic cycles.

What to look for:

• At least 10 years of continuous operation in commercial roofing (not residential)
• Experience with the specific roofing system you are considering
• A history of working on buildings similar to yours in size, type, and complexity
• Stability in their workforce, indicating they retain experienced crews rather than cycling through temporary labor

Why it matters: A contractor who was not in business 10 years ago will not be around to honor a 20-year warranty. Longevity in the industry is one of the strongest indicators that a contractor delivers quality work and operates their business responsibly.

4. What Manufacturer Certifications Do You Hold?

Manufacturer certifications are one of the most meaningful qualifications a commercial roofing contractor can possess. Major roofing material manufacturers, including Carlisle, Versico, Elevate, Johns Manville, and GAF, offer certification programs that require contractors to demonstrate technical proficiency, complete factory training, and maintain quality standards.

Why certifications matter:

• Certified contractors receive factory training on the correct installation methods for each roofing system
• Certification qualifies the contractor to offer the manufacturer's strongest warranty programs, including labor and material warranties that last 20 to 30 years
• Manufacturers inspect a percentage of certified contractors' installations to verify quality, creating an external accountability check
• Certified contractors receive priority technical support from the manufacturer when questions or issues arise during installation

What to ask: Request a list of current manufacturer certifications and verify them directly with the manufacturer. Ask specifically which warranty programs the contractor is authorized to offer. The difference between a standard material-only warranty and a full system warranty with labor coverage can be worth tens of thousands of dollars if a problem arises.

5. Can You Provide References from Similar Projects?

Any reputable commercial roofing contractor should be willing and able to provide references from recent projects similar to yours. References give you the opportunity to hear directly from other building owners about their experience with the contractor.

What to ask references:

• Was the project completed on time and within the agreed budget?
• How did the contractor handle unexpected issues or changes?
• Was the job site kept clean and organized?
• Were you satisfied with the communication throughout the project?
• Have you experienced any problems with the roof since installation?
• Would you hire this contractor again?

Go beyond the provided list. Ask whether you can visit a completed project to see the contractor's work firsthand. Check our project portfolio for examples of completed work. Look for online reviews on Google, the Better Business Bureau, and industry-specific platforms. A strong reputation should be consistent across multiple sources, not just the hand-picked references the contractor provides.

6. What Warranty Coverage Do You Offer?

Commercial roofing warranties can be confusing because there are multiple types that provide very different levels of protection. Understanding what you are getting is essential to making a fair comparison between contractors.

Types of commercial roofing warranties:

Manufacturer material warranty. This covers defects in the roofing materials themselves. It does not cover installation errors or workmanship issues. Material warranties are typically 10 to 20 years and are the minimum level of coverage available.

Manufacturer system warranty (NDL warranty). A No Dollar Limit (NDL) warranty covers both materials and labor to repair any defects in the roofing system for the warranty period, typically 15 to 30 years. This is the strongest warranty available and is only offered through manufacturer-certified contractors whose installation has been inspected and approved.

Contractor workmanship warranty. This covers the contractor's installation work, separate from the manufacturer's warranty. A reputable contractor should offer a workmanship warranty of at least 2 to 5 years. Be wary of contractors who do not offer any workmanship warranty or who offer one that is shorter than industry standard.

Questions to ask about warranties:

• Is the warranty a material-only or full system (NDL) warranty?
• What is the warranty term, and is it prorated or non-prorated?
• What specific conditions void the warranty?
• Does the manufacturer inspect the installation before issuing the warranty?
• What is the contractor's workmanship warranty term?

7. What Is Your Safety Record and Program?

Commercial roofing is one of the highest-risk trades in the construction industry. Falls from height, burns from hot materials, and exposure to extreme temperatures are constant hazards. A contractor's commitment to safety speaks directly to their professionalism and the quality of their operation.

What to evaluate:

• Experience Modification Rate (EMR). This workers' compensation metric compares the contractor's claims history to the industry average. An EMR below 1.0 indicates a better-than-average safety record. An EMR above 1.0 indicates more claims than average. Ask for the contractor's current EMR and trend over the past three years.
• Written safety program. A qualified contractor should have a comprehensive written safety program that covers fall protection, hot work procedures, personal protective equipment, hazard communication, and emergency procedures.
• Safety training. Ask how often employees receive safety training, whether the company employs a dedicated safety manager or officer, and whether they hold any safety certifications such as OSHA 10 or OSHA 30.
• OSHA history. You can search the OSHA inspection database for any contractor's history of citations and violations.

Why it matters to you: A contractor with a poor safety record puts your building, your occupants, and your liability exposure at risk. If an uninsured or underinsured worker is injured on your property, you could face significant legal and financial consequences.

8. How Do You Manage Projects and Communicate with Building Owners?

The quality of project management and communication often determines whether a roofing project feels like a smooth, professional experience or a disorganized ordeal. Before signing a contract, understand how the contractor manages the work and keeps you informed.

Key project management questions:

• Who will be my primary point of contact throughout the project?
• Will a dedicated project manager be assigned, and will they be on site daily?
• How will you communicate progress updates, schedule changes, and any issues that arise?
• What is your process for managing change orders if the scope of work needs to change?
• How do you handle material deliveries and staging to minimize disruption to building operations?
• What is your plan for protecting the building interior and occupants from dust, debris, and noise during the project?
• Who handles permit applications, inspections, and coordination with the building department?

A well-run commercial roofing company will have clear answers to every one of these questions. They will assign a specific project manager to your job, provide regular written updates, and have established processes for handling the inevitable complications that arise on any construction project.

Comparing Proposals: Looking Beyond the Bottom Line

Once you have gathered proposals from three or four qualified contractors, resist the temptation to simply choose the lowest price. Commercial roofing proposals can vary by 20 to 40 percent for the same building, and understanding why is crucial.

Check that proposals are truly comparable:

• Same roofing system and membrane thickness
• Same insulation type, thickness, and R-value
• Same scope of tear-off (full tear-off versus overlay)
• Same warranty type and term
• Same edge detail and flashing specifications
• Equivalent project timeline and start date

A bid that is significantly lower than the others should raise questions, not excitement. The contractor may be using thinner membrane, less insulation, inferior fastening methods, or may not fully understand the scope of work. Alternatively, they may be planning to subcontract the work to less qualified crews. Ask directly about any significant price differences and request written clarification of their scope and specifications.

Making Your Decision

The right commercial roofing contractor will score well across all eight of these evaluation criteria: proper licensing, comprehensive insurance, substantial experience, manufacturer certifications, strong references, meaningful warranty coverage, an excellent safety record, and professional project management. Price should be one factor in your decision, but it should not be the only factor or even the most important one.

Your commercial roof is a major investment that will protect your building for 20 to 40 years. The contractor you choose will determine whether that investment performs as expected or becomes a source of ongoing problems and premature replacement costs. Take the time to ask these questions, verify the answers, and make a decision based on the full picture.

Windward Roofing & Construction welcomes every one of these questions. With 40 years of continuous operation, manufacturer certifications from every major producer, a comprehensive safety program, and hundreds of satisfied commercial building owners across the Midwest and Florida, we are confident in the answers we provide. Contact us to discuss your project and see why so many building owners trust Windward with their most important building component.

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