Choosing a commercial roof contractor can be one of the most important decisions you make as a property owner or manager. The stakes are high—your roof protects your business, inventory, equipment, and staff from the elements. A poor installation or unreliable contractor can lead to serious consequences like water damage, safety hazards, or expensive repairs.
The commercial roofing industry is filled with contractors of varying experience levels, specialties, and business practices. Knowing how to vet the right one ensures you avoid costly mistakes and get a roof that performs reliably year after year.
At Mountaintop Roofing Inc., we’ve worked with commercial clients across Calgary and southern Alberta, helping them make informed choices about materials, system types, and most importantly—contractors. This guide shares expert-level insight into what to look for when hiring a commercial roofing company.

Understand the Unique Demands of Commercial Roofing
Before choosing a contractor, it’s essential to understand that commercial roofing is vastly different from residential roofing in both scale and complexity.
Key Commercial Roofing Challenges:
- Flat or low-slope systems require specialized membranes and drainage systems.
- Larger surface areas mean installation time, material logistics, and labor planning are more critical.
- Code and compliance requirements must be strictly followed to pass inspections and qualify for warranty coverage.
- Long-term performance is a must, as business operations rely on uninterrupted protection from weather and moisture.
Given these considerations, choosing the right commercial roof contractor isn’t just a hiring decision—it’s a business investment.
Start With Proven Commercial Experience
Not all roofers who offer commercial services have the qualifications to handle large-scale or specialty jobs. It’s crucial to hire a contractor with a verifiable track record in commercial projects.
Look for These Credentials:
- Years in Business: Longevity shows stability and experience.
- Commercial References: Ask for contactable references from past commercial clients, especially those with similar building types.
- Portfolio: Reputable contractors should have photos and documentation of completed commercial roofing projects.
- Specialty Certifications: Look for manufacturer certifications specific to commercial systems such as EPDM, TPO, PVC, and modified bitumen.
Commercial contractors should be well-versed in building codes, roofing system compatibility, and local climate needs.
Verify Licensing, Insurance, and Bonding
One of the biggest red flags in commercial roofing is working with a contractor who lacks proper licensing or insurance. Even if the quote is lower, the risks are much higher.
Essential Documentation:
- Business License: Verify that the contractor is registered and licensed to operate in your province or municipality.
- Workers’ Compensation Insurance: This protects you from liability if a worker is injured on your property.
- General Liability Insurance: Covers damage to your building during the roofing process.
- Bonded Contractor: A bonded contractor provides added financial protection in case they fail to meet their contract obligations.
You can confirm business licenses and records through your local provincial business registry or municipal licensing office.
Get Clarity on Materials and Installation Methods
A good commercial roof contractor doesn’t just talk about price—they explain materials, processes, timelines, and expected performance. Ask these questions:
- What type of roofing systems do you recommend for my building and why?
- Are the materials rated for local weather, hail, and snow loads?
- How is moisture management and drainage handled?
- What is the expected lifespan of the roof?
Choosing high-performance materials and an experienced team helps protect your building from Calgary’s unpredictable weather and reduces future maintenance costs.
Ask About Warranties – Both Material and Workmanship
Every quality roofing system should come with two key warranties:
- Manufacturer Warranty: Covers defects in roofing material.
- Workmanship Warranty: Covers installation errors.
A contractor unwilling to offer or explain these warranties should not make your shortlist. Ask specifically:
- What is covered under each warranty?
- How long is the workmanship warranty valid?
- Are there conditions that could void the warranty?
Ensure that all warranty terms are included in your final written agreement—not just discussed verbally.
Review Safety Standards and On-Site Protocols
Safety is non-negotiable in commercial roofing. A responsible contractor will adhere to all Occupational Health and Safety (OHS) regulations, provide safety training to crews, and use the appropriate fall protection equipment.
Key safety practices should include:
- Fall protection systems
- Scaffolding or guardrails
- Daily site clean-up
- Documented safety policies
You can read more about Canadian workplace safety standards through Canada’s Centre for Occupational Health and Safety.
Evaluate Their Communication and Responsiveness
Professionalism starts with communication. From the first phone call or email, take note of how promptly and clearly a contractor responds.
Look for contractors who:
- Offer clear and written estimates
- Are willing to explain their process in detail
- Respond quickly to questions or concerns
- Assign a dedicated project manager or point of contact
During your selection process, poor communication is often a preview of project delays and misunderstandings down the line.

Compare Estimates – But Don’t Shop on Price Alone
It’s tempting to choose the lowest bid, especially for large projects. But the cheapest commercial roofing quote is often the most expensive long-term, especially if it leads to future repairs, leaks, or voided warranties.
What a Proper Commercial Estimate Should Include:
- Breakdown of material costs
- Labor estimates
- Equipment fees
- Safety considerations
- Disposal or recycling of old materials
- Timeline and milestones
- Warranty terms
Choosing a contractor with a detailed estimate helps you avoid budget surprises and track the quality of the job from start to finish.
Look for Local Knowledge and Reputation
Contractors with local experience are more familiar with:
- Calgary weather patterns
- Regional building codes
- Municipal permit requirements
- Common materials for commercial structures in Alberta
Reputation matters. A company rooted in the local community is more likely to be available for warranty support, ongoing maintenance, or future inspections.
You can verify reputation through:
- Google Reviews
- Better Business Bureau
- Referrals from property managers or local businesses
- Industry affiliations such as NRCA or CRCA
Why Mountaintop Roofing Inc. Is the Commercial Roofer Businesses Trust
At Mountaintop Roofing Inc., we’ve built a reputation as Calgary’s trusted source for reliable, high-performance commercial roofing. We bring decades of experience, high-quality materials, and a commitment to communication and craftsmanship that you can depend on.
What Sets Us Apart
- Local Expertise: We know what it takes to build a roof that performs in Alberta’s climate—rain, snow, or shine.
- Commercial Credentials: Our team is trained and certified in leading commercial roofing systems, from metal to membrane-based solutions.
- Upfront Estimates: No surprises, just clear, detailed pricing and scope documentation.
- Jobsite Professionalism: We respect your property, staff, and schedule—minimizing disruptions to your business.
From office buildings and retail complexes to industrial warehouses and institutional buildings, we handle commercial projects with precision, speed, and accountability.
Let’s Talk About Your Commercial Roofing Needs
Hiring the right commercial roofing contractor isn’t a simple task—but it’s a critical one. You need a partner who brings the right mix of experience, safety, product knowledge, and integrity to every job.
At Mountaintop Roofing Inc., we treat every commercial project like our own business depends on it—because it does. If you’re planning a roofing replacement, repair, or new construction, we’re here to help with honest advice and professional service.
Get a free estimate now and see why more Calgary businesses trust Mountaintop Roofing Inc. to protect their property and investment.