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Flat & Low-Slope Roofing — Greater Seattle Metro
PVC & TPO Flat Roof Replacement — Seattle Metro
PVC and TPO membrane roof replacement for flat and low-slope residential roofs in the Seattle metro area. Heat-welded seams, proper slope correction, and drain detailing — backed by a 10-year workmanship warranty.
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Roofing
Heat-Welded Seams
All seams hot-air welded to exceed membrane strength — no glue, no tape, no lap joints.
PVC & TPO Both Available
We specify the correct membrane for your application — not the one with the highest margin.
Slope Correction
Tapered insulation to direct water to drains when existing slope is insufficient.
Drain Audit Included
Every interior drain, scupper, and overflow inspected and cleared before installation.
Garage, Addition & Home Roofs
Flat section on any structure — detached garage, addition, or full flat-roof home.
10-Year Workmanship Warranty
Every flat roof installation backed by our workmanship guarantee.
Service Options
Choose What Works For You
Annual
Home Care Program
Bundle & save on annual roof and gutter cleaning
What You Get:
- 10% off each cleaning
- 1–2 visits per year
- Gutter and downspout cleaning
- Gutter polishing
- Comprehensive gutter inspection
- Roof cleaning and maintenance
- Comprehensive roof inspection
- Storm cleaning
- Priority cleaning & inspection after storms
One-Time
Roof Cleaning
What You Get:
- 1 professional roof cleaning
- Moss & algae soft-wash treatment
- Debris clearing from all surfaces
- Preventive anti-growth application
- Minimize damage caused by moss & debris
- Increase roof lifespan
- Identify concerns before they cause issues
Annual
Roof Maintenance
What You Get:
Everything from a one-time cleaning plus:
- 5% off each cleaning
- 1–2 cleanings per year
- Roof inspection & condition report
- Priority scheduling
- Priority cleaning & inspection after storms
One-Time
Gutter Cleaning
What You Get:
- 1 professional gutter cleaning
- Full debris removal from troughs
- Downspout flushing & clearing
- Flow test and inspection
- Hanger inspection
Annual
Gutter Maintenance
What You Get:
Everything from a one-time cleaning plus:
- 5% off each cleaning
- 1–2 cleanings per year
- Gutter inspection & condition report
- Priority scheduling
- Priority cleaning & inspection after storms
PVC vs. TPO
Understanding the Difference — and Which One Is Right for Your Roof
PVC and TPO are both heat-welded single-ply membranes — the correct specification for flat and low-slope residential roofing in Seattle's climate. They are installed using the same method and deliver comparable service lives. The differences matter for specific applications. Here is how we think through the decision.
PVC (Polyvinyl Chloride) Roofing
PVC (polyvinyl chloride) single-ply membrane is the premium specification for flat and low-slope roofing in the Pacific Northwest. It is heat-welded at every seam, creating a bond that is stronger than the membrane itself — not glued, not taped, not lapped. On Seattle-area homes where the flat section is over heated space — a master bedroom addition, a second-story deck with living space below, or a flat-roof contemporary build in Bellevue or Kirkland — PVC is the correct material. It tolerates the sustained pooling that comes with flat roofs in 38-inch annual rainfall without seam separation or membrane fatigue. PVC is also the correct choice when the flat section is adjacent to a cooking exhaust vent or mechanical equipment that might discharge oils — grease dissolves TPO membranes but does not attack PVC.
- Superior chemical resistance — resists oils, grease, and restaurant exhaust
- Stronger seam welds — heat-welded seams exceed membrane tensile strength
- Excellent low-temperature flexibility down to –40°F
- Typical service life of 20–30 years in PNW conditions
- White surface reflects solar gain — reduces summer cooling load
TPO (Thermoplastic Polyolefin) Roofing
TPO (thermoplastic polyolefin) is the most-installed single-ply membrane in commercial construction and is increasingly the standard choice for residential flat sections, garages, additions, and low-slope porches across Sammamish, Bothell, Issaquah, and Redmond. Like PVC, TPO is heat-welded at all seams — not glued or lapped — creating a continuous waterproof envelope. It performs comparably to PVC in most residential applications and carries a lower per-square cost, making it the right specification for detached garage roofs, covered patios, and budget-sensitive flat-section replacements. For installations adjacent to mechanical exhausts or cooking ventilation, we specify PVC instead.
- Lower material cost than PVC with comparable performance in most applications
- Highly reflective white surface reduces building heat gain
- Heat-welded seams — same installation method as PVC
- Good flexibility across Pacific Northwest temperature ranges
- Excellent resistance to UV, ozone, and biological growth
Installation Process
How We Install a Flat Roof Replacement
Substrate Assessment & Drain Audit
Flat roofs fail at drains before they fail anywhere else. We inspect every interior drain, scupper, and overflow for clogs, deteriorated clamping rings, and improper slope before any new material goes down.
Existing Membrane Tear-Off
All existing roofing material is removed to the deck. We inspect the substrate — typically OSB, plywood, or concrete — for moisture damage, rot, and delamination, replacing any compromised sections before installation begins.
Slope Correction (When Required)
Pacific Northwest flat roofs must drain within 48 hours of precipitation. We use tapered insulation to correct or improve slope toward drains when the existing deck is insufficiently pitched — preventing the chronic ponding that degrades all membrane systems.
Insulation Board Installation
Polyisocyanurate (polyiso) rigid insulation is fastened to the deck, providing both thermal performance and a uniform substrate for membrane installation. R-value is specified to meet or exceed current Washington State Energy Code requirements.
Membrane Installation & Heat Welding
PVC or TPO membrane is rolled out and mechanically fastened at the perimeter. All seams are hot-air welded — not glued — creating bonds that exceed membrane strength. Penetrations, drains, and perimeter terminations are detailed with prefabricated flashings and membrane-compatible sealant.
Flood Test & Final Inspection
We flood-test or inspect all seams and penetrations before sign-off. Every drain is cleared, every termination bar is fastened, and the installation is documented with photos for your records and warranty registration.
Seattle-Specific Context
Why Flat Roofs Need Extra Attention in the Pacific Northwest
Seattle's climate is among the most demanding in North America for flat roofs. Annual rainfall of 38 inches, combined with sustained low-intensity precipitation events that can last days without clearing, means water sits on low-slope surfaces for extended periods. Homes in Bellevue, Kirkland, and Sammamish built during the mid-century flat-roof design era — or homes with flat additions installed after 2000 — are often working with membranes past their service life.
The most common failure points we find on Eastside flat roofs are: deteriorated seams on aging EPDM installations, clogged interior drains that cause chronic ponding, and improper transitions between the flat membrane and adjacent sloped shingle sections. All three are addressed during our replacement process.
Homes in Issaquah Highlands, Klahanie, and Snoqualmie Ridge with modern contemporary architecture often have large flat sections over main living areas — these are the installations where PVC's superior seam strength and cold-temperature flexibility matter most.
Related Roof Replacement Services
We Can Finance Your Project
- Loans from $500 to $200,000
- 0% Promotional APR Financing Available
- Instant Pre Approval
- Soft Pull Available
- 1 to 12 Year Terms
- 60 Sec Application
Where We Work
Flat Roof Replacement Across King & Snohomish County
Our Customers Say It Best
What Homeowners Are Saying About Us
See why property owners across King and Snohomish County choose Real Great Roofing for roof replacements, repairs, and maintenance. Every job done with care and radical transparency.
Google Reviews
Facebook Reviews
Justin Ursu
Roof and gutter cleaning complete - they even went above and beyond and did a free roof inspection to make sure that there were no potential problem areas that could cause a leak if unaddressed. Real Great Roofing did an amazing and fast job with the cleaning. Took good care not to damage the surrounding grass and gardening work, and were quick to complete the job.
Gobirel Wren
I can say enough good things about Real Great Roofing this company. From start to finish, the experience was absolutely amazing. The team arrived on time, worked with great attention to detail, and made sure everything was done perfectly. Their professionalism, honesty, and hard work really stood out. They went above and beyond to make sure I was satisfied with the results, and I truly appreciate the effort they put into every step of the project. The quality of their work exceeded my expectations, and the finished results look incredible. It's rare these days to find a company that genuinely cares about its customers the way they do. I would highly recommend them to anyone looking for reliable, trustworthy, and skilled professionals. Definitely a 5-star service that I will use again in the future.
Phillip Gri
Had a great experience meeting and consulting with Brennan. He is knowledgeable, honest and transparent. He took the time to understand our needs and gave clear, practical guidance without any pressure. Looking forward to working together!
Caleb Spatacean
Asphalt shingle roof replacement on the east side. Did an amazing job and were very communicative. Plan to work with them for roof and gutter maintenance in the future!
Petra Newman
I recently had the pleasure of working with Real Great Roofing for a roof repair project, and I was thoroughly impressed with their customer service. From the initial phone call to the completion of the project, their team was friendly, responsive, and attentive to my needs. They kept me informed throughout the process and ensured that I was satisfied with the results. Their commitment to customer satisfaction is commendable, and I would highly recommend them to anyone in need of roofing services.
Vadim Paripa
Excellent roofing job. Highly recommend. They are punctual, quick, and very communicative.
Coz Ceh
Real Great Roofing was great to work with and made the whole process easy. The crew did an amazing job, and everything turned out better than expected. Brennan was especially awesome, super helpful, honest, and easy to communicate with the entire time. Highly recommend!
Erik Brutsky
TPO roof installation on a new flat roof build. They're remarkably easy to work with as a general contractor. Recommend to both GCs and homeowners.
Joshua Suman
I really did not want to leave this review as five stars and I will tell you why: I WANTED TO LEAVE 6! Did these gentlemen respond to my call, even when I did not leave a voicemail, as I was cold calling multiple places for an emergency fix? They did. Were they courteous, up front, honest, and most importantly, no pressure? They absolutely were. Did they offer to purchase new shingles, in the correct color, at no extra charge to me, after I shared I had mistakenly bought the wrong color? Yes! Did they arrive promptly, same day, after allowing me to send some photos of the repair area to provide an initial estimate? Surely they did. Most of all, was the work of the absolute highest quality, completed in good time and order, with care for craft and my piece of mind as the top priority? I can say, beyond a shadow of a doubt, YES! If you want the job done quickly, done right, by honest folks with integrity and character, call Real Great Roofing.
Filipp Kishko
Some of the best in the business! Ben and Brennan are men of integrity and the quality finish reflects that!
Justin Ursu
Roof and gutter cleaning complete - they even went above and beyond and did a free roof inspection to make sure that there were no potential problem areas that could cause a leak if unaddressed. Real Great Roofing did an amazing and fast job with the cleaning. Took good care not to damage the surrounding grass and gardening work, and were quick to complete the job.
Gobirel Wren
I can say enough good things about Real Great Roofing this company. From start to finish, the experience was absolutely amazing. The team arrived on time, worked with great attention to detail, and made sure everything was done perfectly. Their professionalism, honesty, and hard work really stood out. They went above and beyond to make sure I was satisfied with the results, and I truly appreciate the effort they put into every step of the project. The quality of their work exceeded my expectations, and the finished results look incredible. It's rare these days to find a company that genuinely cares about its customers the way they do. I would highly recommend them to anyone looking for reliable, trustworthy, and skilled professionals. Definitely a 5-star service that I will use again in the future.
Phillip Gri
Had a great experience meeting and consulting with Brennan. He is knowledgeable, honest and transparent. He took the time to understand our needs and gave clear, practical guidance without any pressure. Looking forward to working together!
Caleb Spatacean
Asphalt shingle roof replacement on the east side. Did an amazing job and were very communicative. Plan to work with them for roof and gutter maintenance in the future!
Petra Newman
I recently had the pleasure of working with Real Great Roofing for a roof repair project, and I was thoroughly impressed with their customer service. From the initial phone call to the completion of the project, their team was friendly, responsive, and attentive to my needs. They kept me informed throughout the process and ensured that I was satisfied with the results. Their commitment to customer satisfaction is commendable, and I would highly recommend them to anyone in need of roofing services.
Vadim Paripa
Excellent roofing job. Highly recommend. They are punctual, quick, and very communicative.
Coz Ceh
Real Great Roofing was great to work with and made the whole process easy. The crew did an amazing job, and everything turned out better than expected. Brennan was especially awesome, super helpful, honest, and easy to communicate with the entire time. Highly recommend!
Erik Brutsky
TPO roof installation on a new flat roof build. They're remarkably easy to work with as a general contractor. Recommend to both GCs and homeowners.
Joshua Suman
I really did not want to leave this review as five stars and I will tell you why: I WANTED TO LEAVE 6! Did these gentlemen respond to my call, even when I did not leave a voicemail, as I was cold calling multiple places for an emergency fix? They did. Were they courteous, up front, honest, and most importantly, no pressure? They absolutely were. Did they offer to purchase new shingles, in the correct color, at no extra charge to me, after I shared I had mistakenly bought the wrong color? Yes! Did they arrive promptly, same day, after allowing me to send some photos of the repair area to provide an initial estimate? Surely they did. Most of all, was the work of the absolute highest quality, completed in good time and order, with care for craft and my piece of mind as the top priority? I can say, beyond a shadow of a doubt, YES! If you want the job done quickly, done right, by honest folks with integrity and character, call Real Great Roofing.
Filipp Kishko
Some of the best in the business! Ben and Brennan are men of integrity and the quality finish reflects that!
Frequently Asked Questions
What's the difference between PVC and TPO — which one should I get?
For most residential applications — garage roofs, additions, covered patios, and flat-roof contemporary homes in Bellevue, Redmond, and Kirkland — TPO delivers equivalent performance at a lower cost. We specify PVC when the installation is adjacent to mechanical exhaust, cooking ventilation, or oils; when the client is willing to pay a premium for maximum seam strength; or when the application demands maximum cold-temperature flexibility.
How long does a PVC or TPO roof last in Seattle?
In Pacific Northwest conditions, a properly installed and maintained PVC or TPO system should deliver 20 to 30 years of service life. The single most important factor in lifespan is seam quality — which is why heat welding is non-negotiable. Seams that are glued or taped fail in Seattle's sustained rainfall within 5 to 10 years.
Flat roof leaking or overdue for replacement?
Free inspection — we identify the actual failure point and give you a written estimate.
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