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Flat Roof Replacements

Watertite Roofing offers top-notch flat roof replacement tailored to meet the diverse needs of commercial, industrial, institutional and residential properties. We install long lasting, watertight and energy-efficient roofing systems.

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    The Go-to Flat Roofing Specialists Since 1976

    With an A+ BBB rating and more than 50 years of experience in the roofing industry, Watertite Roofing has become Ontario’s trusted specialist in flat roof installations, repairs, replacements, retrofits, and maintenance services. For property owners, this means working with a roofing contractor that combines proven expertise with modern roofing solutions.

    Flat Roofing Materials that Withstand Ontario Weather

    From Guelph and Hamilton to Burlington, Brantford, St. Catharines, Niagara Falls, and Fort Erie, Watertite Roofing provides tailored solutions for every roofing need. We understand the diverse flat roof challenges posed by Ontario’s weather and building requirements. That’s why we focus on using the best materials like Duro-Last roof membranes to ensure watertight flat roofs.

    Therefore, property owners can rely on us to replace their damaged flat roofs, reduce risks of water damage, and ensure uninterrupted business operations through dependable flat roof replacements and maintenance services.

    Trained, Certified, and Experienced Roofers

    Our team of certified flat roofing professionals brings decades of combined experience to every project we undertake. We use advanced roofing techniques and the right materials to install, repair, or replace roofing systems to ensure your new roof can withstand Ontario’s toughest weather conditions.

    Each member of our team undergoes professional training and a thorough certification process to ensure they can handle roof repairs, installation, maintenance, and replacements successfully. When you choose Watertite Roofing, you partner with roofing experts who understand the critical importance of a leak-free flat roof.

    Watertite Roofing is Industry Recognized

    Watertite Roofing has built its reputation on consistent results. We have more than 6,700 completed projects, and over 78% of our clients are from referrals or repeat clients. Also, we’re recognized as Ontario’s #1 flat roofing specialist and have maintained a 4.9-star average on Google. Thus, our reputation for quality flat roof repairs, installations, maintenance, and replacement speaks for itself.

    Industry recognition has further highlighted our dedication to offering cost-effective flat roof replacements and other roofing solutions. In 2020, we received ongoing service awards and earned the status of Duro-Last Elite Contractors. We also secured the Duro-Last Elite Contractor designation once again in 2023, along with the General Award for Outstanding Achievement in quality workmanship and customer satisfaction.

    In 2024, our team was once more honored with the Duro-Last Elite Contractor status and the prestigious General’s Award at the Contractor Awards Gala in Hollywood, California. These milestones reflect our technical expertise in flat roofing and our unwavering commitment to quality and customer trust.

     

    Why Duro-Last and Goliath Roofing Systems for Flat Roof Replacements?

    Sometimes, flat roof repairs aren’t enough. When you’re dealing with extensive roof damage, structural damage to the decking, or your roof is old, we may recommend flat roof replacement. Our experienced flat roofing experts will perform a thorough roof inspection to assess the nature and extent of the roof damage. We’ll also recommend repairs, or partial or complete replacement with a Duro-Last or the Canada-made Goliath roof system. Here’s why we recommend these systems for flat roofing projects.

    Installation Options

    Overlay/Retrofit

    Duro-Last and Goliath flat roofing systems are versatile and allow for various installation methods to match different roofing needs. For instance, if a property owner is proactive in replacing their roof and the existing substrates have not become saturated with water due to excessive roof leaks, our roofing professionals can cap-over the existing roofing substrates in an overlay/retrofit installation.

    Overlying or retrofitting allows our roofers to install the Duro-Last or other Canada-made roofing membranes like the Goliath system directly over an existing roof substrate. This roofing approach saves significant money on the necessary materials and labor. It also minimizes disruption to your facility’s daily operations and generally leads to a faster installation.

    Full Replacement

    Suppose the existing roof substrate is saturated with water or shows signs of extensive damage. In this case, our roofing professionals may recommend replacement. Such a roofing project requires us to remove all existing roofing materials and insulation before installing a Duro-Last single-ply system or Goliath roof assembly.

    Extended Roof Life

    Retrofitting or overlaying an existing roof with a Duro-Last or Goliath roof system extends the lifespan of the existing roofing susbstrates and delays the need for another full replacement. Duro-Last and Goliath flat roofing membranes are known for their durability. Thus, they provide consistent protection against harsh weather for decades.

    This long-term performance reduces ongoing maintenance costs and the need for frequent flat roof replacement. Therefore, using top-quality, time tested, flat roofing materials offers real financial value to industrial and commercial building owners.

    Energy Efficient & UV Resistant Roofs

    Goliath and Duro-Last flat roofs are engineered for energy efficiency. These roofing systems have UV-resistant, reflective surfaces that reduce heat absorption and keep buildings cooler in summer. This lowers overreliance on HVAC systems, resulting in reduced energy use and lower utility bills.

    In addition, commercial flat roofs require minimal maintenance because the membrane is resistant to mold, mildew, and algae growth. Their smooth surfaces also prevent debris buildup and drainage system issues. When maintained properly, these roofs are energy efficient and durable.

    No Wastage of Roofing Materials

    Capping over an existing roof with a Duro-Last or Goliath retrofit or overlay roof assembly helps conserve resources by extending the service life of your current roofing system. Instead of completely tearing off your existing roof, the overlay method allows us to install the new roofing membrane on top of the existing substrates (if they’re in good condition), preserving their value.

    This flat roof installation method enhances performance and durability without requiring large quantities of new roofing materials. Therefore, it lowers the overall environmental footprint of a roofing project. Remember, we only recommend complete roof tear-off and replacement if, after a thorough inspection, we determine that your flat roof is extensively deteriorated.

    Recyclable Flat Roof System

    The “Recycle Your Roof” initiative from Duro-Last gives property owners an environmentally responsible option for roof disposal. Instead of sending old roof membranes to landfills, this program collects and recycles them for reuse in new products.

    The program keeps old roofing materials away from the waste stream. Thus, it supports a circular approach to flat roofing, a process that gives used roofing membranes a second life. This reduces landfill burden and demonstrates a clear commitment to sustainability.

    Top-Quality Flat Roofing Systems

    The Duro-Last roofing system and Canada-made Goliath roofing assemblies we recommend are engineered to withstand even the harshest weather conditions. For instance, the Duro-Last and Goliath systems have heat-welded seams and a watertight design that offers superior protection against leaks.

    Unlike most flat roof systems with vulnerable joints and seams, Duro-Last an Goliath flat roof assemblies offer a watertight barrier against water leaks and moisture infiltration. Thus, your commercial property or industrial facility will be protected from water damage. Remember, the PVC membrane is resistant to tears, punctures, and other forms of roof damage.

    Ready for a new roof?

    At Watertite Roofing, we’re committed to offering superior flat roof replacements and other roofing solutions that combine innovative technology with quality craftsmanship. We leverage our 50 years of combined experience and wealth of flat roofing knowledge to ensure that owners of industrial facilities, commercial properties, and residential homes can get the best value for their investments in flat roof replacement.

    Our Flat Roof Inspection Can Save You Thousands

    A proper flat roof inspection is the first step to keeping your property protected year-round. In Ontario, flat roofs face heavy rain, snow buildup, and rapid freeze-thaw cycles that test every roofing seam. A professional inspection helps identify issues like clogged drains, trapped moisture, and weak membrane areas before they cause costly leaks or structural damage.

    Our roofers check every section for water pooling, cracks, and improper slope that can slow drainage. They also inspect vents, flashing, and joints to ensure water moves freely toward drains or scuppers. Modern drainage systems are designed to prevent standing water and extend roof life.

    Whether your building uses internal drains or external downspouts, keeping them clear is essential for long-term performance. Regular inspections every spring and fall can save thousands in repairs and keep your roof performing at its best.

    Flat Roof Installation in the Ontario Winter

    Modern flat roofing systems and cold-weather compatible materials allow our roofing contractors to complete installations safely and effectively, even in freezing temperatures. The key is preparation, precision, and using products built to handle the season.

    A cold-weather flat roof installation follows a careful process:

    • Site Preparation: Clear snow, ice, and debris to create a clean surface.
    • Moisture Control: Ensure the substrate is dry before applying any roofing layers.
    • Material Selection: Use flexible membranes designed for cold application.
    • Temperature Monitoring: Work during daylight hours when conditions are most stable.
    • Seam Sealing: Thermally weld roofing seams with computerized hot-air welding units.
    • Inspection and Cleanup: Double-check seals, flashing, and drainage paths before leaving the site.

    When managed by the experienced roofers at Watertite Roofing, winter installations offer the same strength and weather protection as those done in warmer months. For Ontario businesses that can’t afford downtime, this is a reliable and efficient solution to keep projects on schedule and roofs in good condition year-round.

    What’s the Flat Roof Replacement Cost in Ontario?

    Whenever you think there’s an issue with your roof, let our roofing experts carry out a thorough flat roof inspection. In many cases, targeted flat roof repairs can fix small leaks or other forms of isolated damage and restore your roof’s performance.

    When to Repair Your Flat Roof

    Here’s when we recommend flat roof repairs:

    • Minor cracks, minor flashing issues, and other forms of isolated damage
    • Your roof isn’t old and hasn’t developed membrane buckling or widespread leaks
    • The roof’s membrane, insulation, and the underlying substrate are still in good condition
    • No structural roof damage, and most roof issues are limited to the membrane’s surface

    When to Replace Your Flat Roof

    There are times flat roof repairs won’t cut it. Any minor leaks and small cracks we identify during regular inspections can be fixed through targeted repairs. However, when your flat roof has deep structural issues or the system has surpassed its service life, we may recommend a full flat roof replacement. Here’s when complete replacement makes sense.

    • Large blistered sections, widespread leaks, and extensive damage to your roof
    • Extensive water damage to the insulation, damaged decking, and other structural issues
    • Old roof (over 20 years) that requires costly maintenance
    • Multiple, recurring leaks that indicate structural roof problems

    The specific materials you need for your roofing project will significantly affect the total cost of your flat roof replacement. Work with our team to determine the specific materials you need, their cost, and how to source them.

    Ready to Replace Your Flat Roof?

    Whether you need a flat roof replacement for your commercial, residential, or industrial building, you can count on us to use high-quality materials to ensure your new roof is durable. Contact us for an initial roof inspection and an accurate estimate for costs and project timeline.

    Schedule a free consultation today and let our professional roofers assess your roof.

    FAQs

    The cost of flat roof replacement typically ranges from $6 to $30 per square ft., depending on the roof size, material costs, labor costs, extent of the roof damage, and your roof’s accessibility.
    Flat roof replacement is a big investment that owners of commercial and residential properties make. When faced with a 5-digit roof replacement bill, it can cause hesitation. Consult our flat roofing experts until you find a budget-friendly option to ensure your commercial or industrial facility has an efficient flat or low-sloped roof.
    With proper maintenance, your flat roof can last 20 to 30 years. Pay attention to any signs of damage or inefficiencies and get them fixed on time. Note that routine inspections and professional maintenance can extend the lifespan of your roof - services offered by Watertite Roofing.
    Spring, Summer, and Fall all are the recommended times to replace your flat roof. Winter presents its own roofing challenges in Ontario, Canada. However, we are able to perform roof replacements during the winter as well when required. Consult our team of roofers to schedule your roof replacement at the right time.
    A compromised roof for your property is a financial inconvenience and a safety risk. Water and moisture intrusion can cause rot, mold, and lead to ceiling collapse. In addition, failing to address roof damage can lead to liability issues and insurance claim denials.
    Targeted repairs can extend the lifespan of your roof and offer you valuable time to plan and schedule a full flat roof replacement. Work with the Watertite Roofing team to determine if repairs are a cost-effective option for your commercial or industrial roof.

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      What our customers are saying

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      Zac and his team have been incredible from our first contact. They were the most reasonably priced of 4 quotes, got the job done quickly when they said they would, have promptly responded to any queries and have came back to support installation of ventwork during renovations. The new roof, trim and eaves troughs look great and we’re very happy with the service.

      Amanda Harry

      In February this year, we had a serious flooding problem at our house coming from an outside flat roof deck and probable freezing / ice damage. As part of researching our options, we learned that identifying and fixing flat roof issues can be very complicated, expensive and problematic for insurance coverage. While WaterTite Roofing was not involved in the original installation of our flat deck, Zachary came to our house the day after we contacted him and provided us with a detailed assessment of the problem, a solution and the cost. While we ended up using a different roofing company, mostly due to insurance complications, we could not have been more pleased or impressed by the professionalism of Zachary and we make no hesitation in suggesting you consult WaterTite / Zachary if you have an issue with a flat roof.

      Don Davidson

      Watertite did an amazing job with our rooftop terrace installation, very professional and built to last many years. I would recommend them to anyone looking for a solution that is long lasting and low maintenance. Amazing job!

      Glenn Edwards

      We hired Watertite Roofing to repair a leaking flat overhang on the front of our house that had been poorly done by another roofing company about 10 years earlier. Rot had set in and owner Zak Keyes had the solution for a permanent fix. Lead hand Jon took over from there and skillfully directed his crew to undo all the damage, working tirelessly in cold weather to give us a house that looks great and the knowledge that the problems are fixed for good. We highly recommend Watertite Roofing for flat roof construction and repair. Leanne and Pierre – Hamilton Ontario

      Leanne Joanisse

      Great responsiveness, good value and no hidden costs. Would not hesitate to recommend this company to anyone needing roof work. Chris Elgar of C Elgar Holdings Limited.

      Chris Elgar

      During a heavy rain event, the roof leaked and one of the tenant was concerned about the leak. I called Watertite Roofing and they were on the roof to patch the leak by end of the same day. In the meantime, they did an assessment of the roof and provided a quotation within days for the replacement of the roof. Once the quotation was approved, Watertite Roofing promptly began to replace the roof the following day. The foreman on site for Watertite Roofing was considerate of intrusion to the businesses and their clients. The site foreman was approachable and made changes requested by the landlord. The work was completed in four days and before the next rainfall. Communication with the head office was always pleasant and frequent updates were provided every several days of work progress by the Operations Manager/Estimator. I was pleased with the quick response and the professional manner in which the work was completed ahead of time.

      Silvio Mucciarelli

      Thank you Ibrahim, We really appreciate your Google rating us five stars. Can you share a few words about your experience please as it would be helpful for fellow Googlers. Thank you kindly from Management and Staff

      Ibrahim Jame Mosque

      I had the opportunity to work with Watertite in 2008, they educated me on their product along with the installation process. The job was completed in a diligent and timely manner and the material is a superior technologically advanced product. Most recently, I had an ice issue this past December where Watertite came out to my building to tackle an ice issue. Upon completion, I was shocked to hear from Zak that there was NO charge for the time spent. There are a very few out there that exercise honest ethical business practice…….THANK YOU

      Zappa Zappa

      After doing a lot of research on possible solutions for renewing an existing 35yr old low pitch corrugated metal roof on a pre-eng industrial building; a membrane overlay system was chosen as the most effective from a performance, cost and warranty standpoint. After engaging 3 local firms for proposals, it quickly became apparent that Watertite was by far the best solution to meet our needs. Their rep (Zak) was very easy to work with, maintained great communications, and was very professional/responsive to any questions or communications I had. Through the whole process (survey, quotation, project coordination/execution, and wrap-up), Watertite and their personnel were top notch with little inconvenience to the tenant. Definitely would not hesitate to highly recommend Watertite and the Duro-last membrane system.

      Dave Allan

      Zak at Watertite was fantastic! Called him up to get a quote and was very happy with the responsiveness. The work was completed as promised and in a very professional. Would definitely recommend them for any roofing needs.

      D. B.

      The crew from Watertite Roofing did and amazing job. They were professional and friendly and worked hard to get the job done. Quality of work was fantastic. It even cost less than originally quoted and appreciated the honesty. Highly recommend this company.

      J. W.

      this team was excellent! they repaired our roof (a former elementary school) and did the work on time and within budget. The crew were friendly, professional and cleaned up all during the project work. We have asked them to quote us a second building and look forward to having this repaired. They are the experts in flat roofs. Great work Watertight!

      Joanna Mataya

      As a custom home builder and renovator we work on many unique projects that require unique products and solutions. We only work with contractors that can provide the level of professionalism, service, and product quality that we demand of ourselves for our clientele. Watertite Roofing is one of those contractors who sets the bar higher for others. Their response time, organization of operations, and delivery on service is rarely paralleled. And they install a durable, well warrantied product that takes a load off our minds. We wouldn’t use anyone else.

      David Tucker

      In 2018 the team at Watertite installed a new flat roof on our building. Being that it was fairly new product and procedures to us we were a bit apprehensive at first. However, Zak and the team were great to deal with in terms of explaining the new product and installation procedures and it really eased our mind during the decision making process. During installation the team couldn’t have been better. Quick, clean and efficient, very knowledgeable and upon completion they took the time to explain the do’s and don’ts as well as general maintenance tips for us to follow. This past week during the excessive snow storms we’ve had in our area we had some water dripping into our office and showroom. Zak had a team member over the next business day to have a look, at no charge. He did the best he could to clear the water and ice from a frozen eavestrough and downspout that was causing water to travel behind siding and under the membrane. We are very grateful for them to have come out so quickly and not even charge us even though the leak wasn’t even from their roof installation! We have another project in the works for the spring time and we will definitely be going with the team at Watertite again!

      Steve Yendt

      We did our due diligence on roofers when we needed a complete new 15,000 square foot flat roof. All signs were positive for Watertite and they did not disappoint us, they did a great job. Zack was our main contact and he kept us informed throughout the project and always returned our calls in a timely fashion. Well done Watertite team! Larry Fontaine, president of Fontaine Transport Inc.

      Barb Fontaine

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