COMMERCIAL ROOFING SOLUTIONS THAT WORK AS HARD AS YOUR BUILDING

Membranes. Coatings. Done Right.

Who installs commercial flat roofing in New Hampshire and southern Maine? J. Carnes & Son Roofing installs, repairs and replaces commercial flat and low slope roofs across New Hampshire and southern Maine, including EPDM rubber, TPO and modified bitumen systems. Crews are GAF certified, licensed and fully insured, and work around your building hours so the business keeps running. Coverage runs from the Seacoast through Nottingham, Salem, Exeter and Portsmouth into York County, Maine. Free commercial estimates at 603-686-7763.

The short version

We install EPDM rubber and TPO membrane roofs on flat and low slope commercial buildings, and restore aging roofs with the GAF HydroStop coating system.
We are certified by both Carlisle and GAF, so the manufacturer warranty on your roof is real and registered, not just a line on an invoice.
We own our telehandlers, coating sprayers and trucks. No rental delays, no subcontractors on your roof, and we control the schedule.
Every job starts with a free inspection and a written scope that covers insulation, drainage, penetrations and local code, so there are no surprises mid project.

At J. Carnes & Son Roofing, we understand the demands of commercial roofing—and we meet them with unmatched precision, performance, and professionalism. Whether you’re installing a new membrane system or restoring an existing roof with advanced coatings, our team delivers solutions that last.

We don’t rent equipment. We own and operate our own telehandlers, industrial roof coating sprayers, and large-capacity trucks, giving us full control over scheduling, logistics, and quality. We’re also certified by Carlisle and GAF, ensuring your project meets the highest standards for warranty and performance.

TAILORED ROOFING SYSTEMS FOR COMMERCIAL-GRADE PROTECTION

MEMBRANE SYSTEMS

EPDM & TPO Roofing

Durable, energy-eﬃcient membrane systems for flat and low-slope roofs. Perfect for large commercial buildings needing long-term performance and low maintenance.

COATING SYSTEMS

GAF HydroStop® PremiumCoat System

A seamless, waterproof solution that restores existing roofs and extends their life—without the cost of a full tear-oﬀ.

Why Choose J. Carnes & Son Roofing?

In-House Equipment, No Delays

We own our telehandlers, roof coating sprayers, and hauling trucks—giving us full control over logistics, scheduling, and on-site eﬃciency.

Certified by Carlisle & GAF

Our team and trusted subcontractor partners are factory-trained and certified, ensuring every installation meets strict warranty and code requirements.

Experienced Project Oversight

Every project is led by our internal team, ensuring subcontracted crews meet our standards for quality, safety, and professionalism.

Clear Bidding. No Surprises.

We’re transparent from day one. You’ll get accurate pricing, realistic timelines, and a team that shows up ready to perform.

Ready to Protect Your Investment?

Our commercial team is standing by to provide custom solutions, expert installation, and full warranty protection.

Call now or click below to schedule a site visit and get a free commercial roof estimate.

Commercial Roofing Built for New England Businesses

When your building needs commercial roofing that stands up to nor’easters, heavy snow load, and constant freeze-thaw cycles, the system matters as much as the installer. J. Carnes & Son installs EPDM rubber and TPO membrane systems engineered for flat and low-slope commercial buildings across New Hampshire and southern Maine — warehouses, offices, retail plazas, and multi-unit properties.

Every commercial roofing project starts with a thorough inspection and a detailed scope: insulation and R-value, drainage, penetrations, and local code requirements. Our GAF-certified crews handle full tear-offs, overlays where appropriate, and roof coating systems like GAF HydroStop that can extend the life of an aging roof for a fraction of replacement cost. Explore our membrane roofing options for EPDM and TPO details.

Downtime costs money, so we plan commercial roofing installations around your business hours and keep the site clean and safe throughout the project. From the first estimate to the final warranty paperwork, you’ll know exactly what is happening and when.

After installation, ask about preventative maintenance plans. Seasonal inspections catch membrane seam wear, ponding, and flashing issues before they become leaks — the cheapest commercial roofing repair is the one you never need. We document every visit with photos so property managers and owners can budget with confidence. Call (603) 686-7763 for a free commercial roof assessment.

Should a commercial building choose EPDM or TPO?

Direct answer: It depends on the building. EPDM rubber is proven, durable and economical for most low slope buildings, and its black surface helps in a cold climate. TPO is white and reflective, which cuts summer cooling costs on conditioned spaces like offices and retail. We inspect the building and recommend the system that fits it, not the one that happens to be on the truck.

The honest answer is that both systems work well in New England when they are installed correctly, and both fail when the seams, flashing and drainage are done badly. A warehouse that is not air conditioned gains little from a reflective roof. A medical office with rooftop units running all summer gains a lot. The membrane choice is a five minute conversation once we have walked the roof and know what sits under it.

Can a commercial roof be restored instead of replaced?

Direct answer: Often, yes. If the deck and insulation are dry and sound, the GAF HydroStop PremiumCoat system goes over the existing roof, seals every seam and penetration, and adds years of service without a tear off. It costs far less than replacement, keeps the building open during the work, and is usually treated as maintenance rather than a capital improvement.

The deciding factor is what is under the surface. We take core samples and moisture readings before recommending a coating, because sealing a wet roof traps the problem. When the substrate is sound, restoration is the smart money. When it is saturated, we tell you plainly that the roof needs to come off. Either way you get the answer before you commit to anything.

How do you keep a business running during a commercial roof replacement?

Direct answer: We plan the work around your hours. Tear off and installation are staged in sections so the building is never open to weather overnight, noisy work is scheduled away from your busiest times, and our own equipment means no waiting on rentals. Most small and mid sized commercial roofs take a few days to two weeks depending on size, tear off needs and weather.

A roofing crew on a working building has two jobs: put on a good roof and stay out of the way. Deliveries go to the side of the building you are not using. Rooftop units are protected and reconnected the same day. Tenants get a schedule they can pass to their staff. We have re roofed retail plazas, warehouses, offices and multi unit properties across New Hampshire and southern Maine without closing a single one.

Commercial Roofing: Your Questions, Answered

EPDM vs TPO, which commercial roofing system is better?

It depends on the building. EPDM rubber is durable, proven and economical for most low slope buildings. TPO is white and reflective, which lowers summer cooling costs for conditioned spaces. We assess your building and recommend the system that fits, not the one we happen to be selling.

How long does a commercial roofing installation take?

Most small to mid sized commercial buildings take a few days to two weeks depending on size, tear off needs and weather. We plan installations around your business hours so operations keep running.

Can a commercial roof be repaired instead of replaced?

Often, yes. Roof coating systems like GAF HydroStop can restore an aging membrane and extend its life by a decade or more for a fraction of replacement cost. A free assessment tells you honestly which path makes sense.

Do you offer commercial roof maintenance plans?

Yes. Seasonal inspections catch seam wear, ponding and flashing issues before they become interior leaks. Every visit is documented with photos so owners and property managers can plan budgets instead of reacting to emergencies.