Commercial Roofing Contractor
Repairs, replacement, and maintenance for commercial properties, HOAs, multifamily buildings, and property managers across Portland and Vancouver.
Flow Roofing provides commercial roof repair and replacement for property owners, HOAs, multifamily buildings, and property managers throughout the Portland metro and Southwest Washington. Our licensed commercial team installs and repairs TPO, PVC, modified bitumen, torch down, and flat roof systems, the most common commercial roofing systems used in the Pacific Northwest.
Repair, Maintain, Restore, Replace
Maximize Roof Life & ROI
Through detailed inspections and preventative maintenance, we identify issues early and address them before they become costly failures. A commercial roof in this region typically lasts 20 to 30 years when properly maintained. Deferred maintenance can cut that lifespan in half and turn a $5,000 repair into a $50,000 replacement. A typical commercial roof inspection takes 1 to 2 hours and results in a written condition report with photos, prioritized recommendations, and honest guidance on whether repair or replacement makes the most sense for your budget. Our maintenance programs help property owners and managers plan ahead, control budgets, and protect their investment year round.
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WHY CHOOSE FLOW ROOFING
When your building has a problem, you need a roofing contractor who shows up, tells you the truth, and gets it done right. We are locally owned, NRCA member certified, and have earned back to back Nextdoor Neighborhood Favorite awards because our customers trust us enough to refer us to their neighbors. We do not upsell replacements when a repair will do, and we do not disappear after the job is done.
Built for Performance Here
Forty three inches of rain a year, high humidity, and winter winds up to 60 mph mean a roof here works harder than one in a drier climate. We know these conditions because we work in them every day. Every system we install is selected for Pacific Northwest weather, completed to manufacturer specs, and backed by appropriate workmanship coverage based on the system installed.
Experienced, Equipped, and Solution-Focused
Our certified technicians have seen every commercial roofing problem this region throws at buildings. TPO seam failures, ponding water on flat roofs, torch down blisters, flashing leaks on multifamily properties. We come to your inspection with the tools and knowledge to diagnose the real problem, not just the symptom, and give you a straight answer on what it will take to fix it.
Get in Touch
Call 503-936-2476 or schedule a free inspection online. Onsite inspection is typically scheduled within 24 to 72 hours. Written estimates follow the inspection and run 24 hours to 2 weeks depending on scope.
Roof damage often goes unnoticed until it becomes a leak. In a climate where rain falls nearly 150 days a year, even minor seam failures or blocked drains can escalate into water damaged insulation, mold, and ceiling collapse that shut down operations. The earlier you catch a problem, the cheaper it is to fix.
Commercial Roofing Services
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Roof inspections and condition assessments
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Leak detection and targeted repairs
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Preventative maintenance programs
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Commercial roof replacement and reroofing
Systems We Work With
Flow Roofing installs and services both low slope and steep slope commercial roofing systems. TPO and PVC membranes are the most popular choice for flat commercial roofs in our region. Both handle heavy rainfall well, with PVC offering superior resistance to ponding water and TPO providing excellent energy efficiency. For steep slope commercial buildings, we work with metal roofing, asphalt shingles, and flat or low slope assemblies depending on pitch, budget, and building use.
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TPO and PVC roofing
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Metal roofing systems
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Asphalt shingle roofing
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Flat and low-slope assemblies
Thermoplastic Roofing Systems (TPO & PVC)
Thermoplastic roofing systems are flexible membranes designed to expand and contract with temperature changes, a critical feature in a climate that cycles through cold wet winters and warm dry summers. TPO and PVC are the two most widely installed commercial roofing membranes in the Portland and Vancouver markets. Both handle heavy rainfall and freeze thaw cycles exceptionally well, typically lasting 20 to 30 years when properly installed and maintained.
Built for Performance
TPO and PVC roofing systems are the go-to choice for low-slope commercial roofs across the Portland metro area due to their:
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Durability and long lifespan, 20 to 30 years
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Strong, heat welded seams that will not peel or separate in wet conditions
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Resistance to moisture, mold, and weather exposure
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Reflective white surface that reduces cooling costs
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Proven performance in high rainfall climates
The key difference. TPO is generally more cost effective at $7 to $12 per square foot installed. PVC costs slightly more at $9 to $14 per square foot but offers superior resistance to ponding water and chemical exposure, the better choice for restaurant rooftops or buildings where water does not drain quickly.
Flow Roofing installs both systems and recommends the right membrane based on your roof slope, drainage, budget, and building use, not whatever has the highest margin.
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Industry-Leading Commercial Roofing Warranties
When a commercial roof fails, the costs go beyond the roof itself. Damaged inventory, disrupted operations, tenant complaints, liability exposure. The warranty behind your roofing system matters as much as the installation. Flow Roofing installs commercial roofing systems backed by some of the strongest warranties available, and we stand behind our own work with workmanship coverage matched to the system installed.
Manufacturer & Workmanship Coverage
We install roofing systems supported by manufacturer warranties that protect against material and installation defects. Because Flow Roofing is a certified installer for our manufacturers, we can offer extended warranty coverage that non certified contractors cannot provide. Workmanship warranties on commercial installations vary by system. Commercial low slope full replacements carry 5 year standard, 10 year upgraded, or lifetime depending on scope. Steep slope commercial installations using our MaxFlow System qualify for a lifetime workmanship warranty. Commercial repairs carry a 1 year workmanship warranty. We walk through warranty options before contract signing so you know exactly what is covered.
No Dollar Limit (NDL) Warranties
NDL warranties are the gold standard in commercial roofing protection and one of the most important things to ask any roofing contractor about. Unlike standard warranties that cap the dollar amount they will pay out, an NDL warranty covers the full cost of repair or replacement, no matter what it costs. Flow Roofing can provide NDL warranties that include:
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Coverage for material and installation defects
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Protection against consequential damage
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Transferable warranty options, valuable if you sell the property
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Coverage that may include ponding water
NDL warranties typically range from 15 to 35 years depending on the system and project specifications. For property managers and building owners making a long term investment, this is the warranty to ask for by name.
Factors That Affect Commercial Roof Replacement Cost
How much does a commercial roof replacement cost is the first question most property owners ask, and the honest answer is that it depends on factors specific to your building. In our market, commercial roof replacement typically ranges from $6 to $18 per square foot installed. For a 10,000 square foot commercial building, that is roughly $60,000 to $180,000 depending on what is involved.
Key Cost Factors
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Condition of existing roof decking. Rotted or damaged decking, common in older buildings, adds $3 to $6 per square foot in repairs before the new roof goes on.
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Type of roofing system. TPO averages $7 to $12 per square foot, PVC runs $9 to $14, metal roofing $12 to $18.
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Total roof size. Larger roofs benefit from lower per square foot costs.
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Roof accessibility and site conditions. Difficult access, rooftop equipment, or multi story buildings add labor cost.
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Drainage performance. Poor drainage may require tapered insulation to correct slope, a common issue on older flat roofs.
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Existing maintenance and repair history. A well maintained roof is cheaper to replace than one with years of deferred damage underneath.
Plan for Long-Term Value
The lowest bid is not always the best value on a commercial roof. A $10,000 difference upfront can mean a 10 year difference in lifespan depending on materials and installation quality. We provide written estimates with no obligation so you understand exactly what is included before signing.
WHAT CAN YOU EXPECT FROM FLOW
Working at heights on commercial buildings comes with real risk. Flow Roofing follows strict OSHA protocols, uses professional fall protection systems, and maintains ongoing training to ensure safe roof repairs, replacements, and installations. Every job site is set up with proper perimeter protection before work begins, protecting our crew, your tenants and employees, and anyone below.
Our commercial roofing professionals are licensed in Oregon, CCB #218471, and Washington, FLOWRR*791Q4, experienced across all major roofing systems used in the Pacific Northwest, and committed to delivering dependable results. After a thorough inspection and detailed written estimate, we provide a clear scope of work so you understand exactly what is happening, why, and what it will cost before anyone gets on the roof.
Poor communication is one of the biggest complaints about contractors. We have built our entire process around solving that. From the moment you schedule an inspection through final walkthrough, you know when the crew is arriving, what they found, what they are doing, and when the job is complete. No surprises and no chasing for an update.
Signs you may need roof repairs or maintenance:
Commercial roof problems rarely announce themselves until the damage is already done. A small seam failure or blocked drain going into October can become a flooded interior by January, and there is no dry season to buy you time. If you notice any of the following, your commercial roof may need attention before the next storm hits.
Visible Roof Damage
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Lifting seams, cracks, or blisters in the membrane
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Bubbling or deteriorating roofing materials
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Loose flashing or damaged shingles around edges and penetrations
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Sagging areas or soft spots indicating compromised decking underneath
Soft spots are a particular red flag. By the time you can feel them underfoot, water has likely already been sitting in your roof deck through multiple rain seasons.
Water & Moisture Issues
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Active leaks or recurring water intrusion after rain
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Water stains or interior ceiling damage, even old stains indicate past or ongoing intrusion
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Musty odors indicating trapped moisture in insulation or decking
Persistent rain and sustained humidity accelerate mold growth and wood rot faster than in drier regions. What is a minor moisture issue elsewhere is an urgent problem here.
System & Performance Concerns
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Previous repairs have failed to resolve the same issues
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Warranty has expired or is nearing expiration
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Increasing energy costs from poor insulation or ventilation
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Clogged drains, gutters, or drainage systems causing ponding water
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If you are checking two or more of these boxes, it is time for a professional assessment. Free commercial roof inspections are available throughout our service area. Schedule online or call.
FLOW THROUGH OUR PROCESS OF GETTING YOUR ROOF REPLACED
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Inspect & Evaluate
Inspect and Evaluate Every commercial property qualifies for a free roof inspection. We conduct a thorough assessment of your membrane, seams, flashing, drainage, and decking, and deliver a written condition report with photos and honest recommendations.
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Estimate & Plan
Estimate and Plan We provide a detailed written estimate with no obligation so you understand the scope, materials, timeline, and what to expect before anyone gets on your roof.
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Schedule & Execute
Schedule and Execute Once you are ready, we schedule your project and show up when we say we will. Our crew works efficiently to minimize disruption to your operations, maintains a clean job site daily, and keeps you updated throughout the installation.
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Deliver Long-Term Performance
Deliver Long Term Performance After installation, we conduct a final inspection against our quality checklist to confirm every detail has been completed to manufacturer specifications and building code.
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Enjoy Piece of Mind
Peace of Mind Your new roof is backed by manufacturer warranty and workmanship coverage matched to the system installed. If anything is not right, we come back and make it right.
Protect the Asset, Protect the Value
A new commercial roof is one of the highest return investments a property owner can make. Beyond weather protection, a properly installed roofing system increases building equity, improves energy efficiency, and is one of the first things a buyer or tenant evaluates when assessing a commercial property. A documented roof replacement with a transferable NDL warranty can be a meaningful selling point. It removes one of the biggest unknowns a buyer faces and signals that the building has been properly maintained.
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Flow Roofing provides commercial roofing services across the Portland metro area and Pacific Northwest including Portland, Beaverton, Hillsboro, Lake Oswego, Tigard, Tualatin, Gresham, Oregon City, West Linn, Wilsonville, the Oregon Coast, and Vancouver, Camas, and Washougal in Southwest Washington.
Licensed Oregon CCB #218471 | Washington FLOWRR*791Q4.
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