Maximizing the longevity of your metal roof

By H. B. Fuller. 

Learn the key steps to protect and extend the life of your metal roof with expert insights on installation, maintenance and repair. 

Metal roofs are revered for their durability, resilience and ability to stand up against nature’s toughest elements. However, achieving a decades-long lifespan depends on more than the metal panels themselves. The real secret to extending the life of a metal roof lies in the materials that seal and support it. With the right sealants, installation practices and maintenance habits, you can safeguard your roof from leaks, UV damage and corrosion, ensuring it remains a steadfast protector for years to come. Here at H. B. Fuller, we look into the essentials of metal roof care, from installation best practices to repair techniques that truly stand the test of time. 

Choosing the right materials can optimize each stage of the life of your metal roof — from installation to repair to regular maintenance.  

Stage 1: Proper metal roof installation prevents problems   

Installing a metal roof using long-lasting materials helps reduce the need for repairs and maintenance. While storm damage is uncontrollable, leaks from vulnerable areas, such as edges, fasteners at seams and flashing around chimneys and other protrusions, can be prevented.  

Butyl tape prevents leaks at metal roof seams  

A study conducted by the Metal Construction Agency on the service life of metal roofs found that sealant was the deciding factor in the service life of a metal roof. Researchers inspected metal roofs, sealed with butyl sealants, across the US and used an independent laboratory to analyze materials. They found no deterioration in tensile strength in the sealants, estimating that butyl sealant service life could last over 60 years.   

Choosing materials like butyl tape, which is proven to have long-lasting strength, is key to preventing costly problems in a roofing assembly. Butyl tape is non-skinning, meaning it doesn’t create a membrane after application and remains tacky and flexible throughout its lifetime. It is also easier to apply evenly than other types of sealants.  

Butyl tape’s greatest strength, the ability to remain tacky over time, is also its biggest downside. Miguel Pena, from H.B. Fuller business development, explains, “Butyl tape creates a waterproof seal between two overlapping panels. In that assembly, the butyl tape can perform its duties over the life of the roof. But its greatest power is also its greatest limitation. Because it doesn’t form a protective layer, it can’t go on the top of panels—where it would be exposed to the sun. The sun will deteriorate it quickly without protection against the elements.”  

Butyl tape is ideal for substrate sealing during installation, where it won’t be exposed to ultraviolet (UV) light. Other products, such as H.B. Fuller’s EternaBond® and FulaFlex™ lines, are ideal for topical repair and maintenance tasks.  

Stage 2: Make repairs with long-lasting sealants  

Metal roofs may become damaged by wind or hail during storms or if materials used in vulnerable areas degrade. Aluminum metal roofs, such as those used on recreational vehicles (RVs), semi-trailers and box trucks, are more likely to require repairs than metal roofs made of other materials. This is because aluminum is more vulnerable to oxidation and stress cracks.     

How EternaBond® tape creates leak-proof sealing  

Topical sealants like H.B. Fuller EternaBond®  semi-permanent roof repair tapes are ideal for leak-proof sealing on damaged roof panels or flashing. EternaBond® products use MicroSealant® Technology formulated with synthetic polymers and a built-in primer. MicroSealant®, creates a waterproof seal resistant to light, heat and environmental factors.  

In addition to instant sealing and leak protection, EternaBond® benefits include:  

• Easy, no-mess application  
• Low-temperature flexibility to -57°C (-70°F) 
• No shrinkage  
• Seals in harsh environments (-40°F to 150°F) 
• Comes in multiple sizes and colors  
• Remains flexible for decades  

The EternaBond® family of sealant tapes can be used in many different ways. Jacque Ince, an H.B. Fuller senior product manager, explains, “Depending on what type of backing you need for your restoration or repair projects based on the type of metal roof, we have a lot of EternaBond products that cater to those needs.”  

When to repair vs. replace a metal roof  

At a certain point, metal roof owners may have to decide between repairing damage to their roof or replacing it entirely. This decision is best made with the help of the metal roof manufacturer and depends on the general condition of each panel and whether the metal roof is on a commercial or residential building.  

When damage is limited to one part of a panel, repairing the panel with EternaBond® is a cost-effective, durable solution. However, if an entire panel is severely damaged or the roofing assembly must be taken apart to make repairs, replacing the entire roof is often more cost-effective. Commercial property owners may choose to build a second metal roof over the damaged one if it can’t be repaired.  

Step 3: Metal roof maintenance   

The first step in metal roof maintenance is simple: visually inspect the roof. Look for rust, warped panels and signs of moisture buildup. Accessing your roof for inspection must be done carefully to avoid falls. The Metal Roofing Alliance recommends hiring a professional. 

In addition to visually inspecting the roof, periodic cleaning will help reduce damage from pollution, dirt and debris from organic material. Since metal roofs are not prone to mildew, they can be cleaned just like a vehicle — with mild detergent and water. Experts at the Metal Roofing Alliance advise applying cleaning solutions with non-abrasive materials and always following manufacturer recommendations.  

A third element of ongoing metal roof maintenance is remaining mindful of any additions to the roof. Metal roofs may become damaged during the installation of equipment like solar panel systems. Checking with the manufacturer before installing anything onto your metal roof is critical to preventing damage.      

Conclusion: Choose from a range of metal roof sealants from H.B. Fuller  

Metal roofs are often billed as a low-maintenance, long-lasting, environmentally friendly alternative to traditional asphalt roofs. While this is true, proper installation, ongoing maintenance and repair with quality materials can extend the life of your roof.  

In addition to the two solutions covered in depth above (EternaBond® and butyl tape), H.B. Fuller offers a wide range of products for use in metal roofs. Applications include topical sealants, exterior repairs, vapor sealants, wall joint adhesives, pole-setting products and more.   

Effective sealants help ensure the service lifetime of your metal roof. Contact an H.B. Fuller expert to explore which sealants are best for your application.  

Original article and photo source: H. B. Fuller