Solutions for aging metal roofs: Pros and cons

By Tim Fowler, Sentry Roofing. 

Metal roofs are known for their long lifespans, but they do eventually start aging. Here’s what to do when that starts happening! 

In the roofing industry, metal has been consistently growing in popularity due to its durability and long lifespan. However, this doesn’t mean that metal is infallible and as it ages, there will inevitably be damage and wear on the roof. If these are not treated properly, they can lead to significant costs for repairs and maintenance. Luckily, for concerned commercial and industrial building owners, the experts here at Sentry Roofing, Inc. have compared the pros and cons of various metal roof solutions that can revitalize your aging roof.  

Metal roof repair and replacement options 

Metal roofing systems are an excellent choice for new buildings. They are structurally sound, stand up to the elements well and offer long life spans. However, as metal roofs age they develop a number of issues such as missing fasteners, failed sealant and flashings, corrosion and damage from continuous thermal movement. Eventually basic repairs are not sufficient and an investment in a long-term solution is necessary. 

There are several factors to consider when deciding on the best course of action for your metal roof, including budget, the severity of the issues and your building’s specific needs. We will explore four main metal roofing options, each with their pros and cons, to help you make an informed decision: 

• Coating 
• Remove and replace 
• Install metal panel retrofit system over the existing metal 
• Install single-ply retrofit system over the existing metal 

By understanding the benefits and drawbacks of each option, you can choose the one that best suits your building and its requirements. In this post, we will provide a comprehensive overview of each metal roofing solution, while subtly emphasizing the advantages of metal retrofitting as the ideal choice for aging metal roofs. 

Sentry Roofing, Inc. is committed to providing valuable insights and expert guidance to building owners with metal roofs. 

By the end of this post, you will have a better understanding of the available options and feel confident in making the right decision for your building’s metal roof. 

Roof coatings - A budget-friendly solution for minor issues 

One of the most cost-effective options for addressing issues with aging metal roofs is the application of a protective coating. Coating systems are specifically designed to provide an additional layer of defense against the elements, helping to extend the lifespan of your metal roof while addressing minor concerns such as rust and small leaks. 

The coating process typically involves the thorough cleaning of the metal roof surface, followed by the application of a primer and a specialized coating material. These materials are formulated to adhere to the metal surface, providing a watertight seal and increased resistance to corrosion and weathering. There are many different coatings on the market with different applications. These can range from lightweight coatings for corrosion resistance to heavy fabric reinforced coatings that can seal seams and small holes. 

Pros of coating 

• Least expensive option: As a budget-friendly solution, coatings are ideal for building owners looking to address minor issues without breaking the bank. 
• Good for stopping rust and sealing small leaks: Coating systems can effectively prevent rust formation and seal minor leaks, enhancing the overall performance of your metal roof. 
• Can increase reflectivity of the roof: Certain coatings are designed to increase the roof’s solar reflectance, which can help reduce energy consumption and cooling costs for your building. 
• Good for increasing the life of a roof with minor issues: Applying a coating can extend the service life of a metal roof that is experiencing only minor problems, delaying the need for more expensive repairs or replacements. 

Cons of coating 

• Warranty limitations: Coating warranties typically cover only the integrity of the coating itself, not the repair of any leaks that may occur during the warranty period. 
• Ineffectiveness for major leaks: Coating systems are not designed to address significant leak issues such as severe corrosion, large holes or damaged seams from thermal movement. Building owners may need to consider alternative solutions for more severe problems. 
• Limited success with repeat coatings: The effectiveness of additional coatings may diminish over time, as the accumulation of multiple layers can result in reduced adhesion and increased risk of coating failure. 

Coatings can be a viable option for commercial and industrial building owners seeking an affordable solution to minor metal roof issues. However, it is essential to recognize the limitations of this option, as coatings may not be suitable for addressing more significant problems or providing long-term protection for aging metal roofs. 

Remove and replace - The complete overhaul 

For building owners facing severe issues with their metal roofs, such as widespread deterioration or loss of structural integrity, a complete removal and replacement of the existing roofing system may be necessary. This option involves the removal of the old metal roof and installation of a brand-new metal roofing system, offering a fresh start and long-lasting protection for your building. 

The process of removing and replacing a metal roof requires careful planning and execution, as well as consideration of factors such as building codes, insulation requirements and compatibility with the existing structure. 

Pros of remove and replace 

• Completely new roofing system: This option provides a clean slate, replacing the old and damaged roofing materials with new, high-quality metal panels. 
• Long life span: A new metal roofing system offers an extended service life, ensuring reliable protection for your building for years to come. 
• Solves major issues with the roof: The removal and replacement process can address significant problems, such as severely deteriorated roofs with compromised structural integrity. 

Cons of remove and replace 

• Typically, the most expensive solution: The cost of completely removing and replacing a metal roof can be substantial, making it one of the most expensive roofing options. 
• Exposure to the elements: During the removal and replacement process, your building may be temporarily exposed to weather conditions, which can be disruptive to ongoing operations. 
• Warranty limitations: Most warranties for new metal roofing systems cover only the metal finish and not leaks. There are some weathertight warranties on the market, but they are not universally available. 
• Impractical for facilities with ongoing operations: The disruptive nature of the removal and replacement process may not be suitable for buildings with continuous operations or sensitive equipment. 
• No insulation or reflectivity improvement: The new metal roofing system generally does not offer any significant improvement in insulation or reflectivity compared to the existing roof. 

The remove and replace option is best suited for commercial and industrial building owners facing severe metal roof issues that cannot be addressed by less invasive solutions. While this option can be costly and disruptive, it provides a long-lasting solution that ensures the continued protection and performance of your building’s metal roof. 

Metal panel retrofit - Maintain the metal aesthetic 

For building owners seeking a solution that maintains the appearance of a metal roof while addressing significant roofing issues, a metal panel retrofit system might be the ideal choice. This option involves installing a new metal panel system over the existing metal roof, providing additional protection without the need for complete removal and replacement. 

The metal panel retrofit process requires careful assessment of the existing roof structure, as well as the design and installation of a compatible new metal panel system. 

Pros of metal panel retrofit 

• Retains metal roofing appearance: A metal panel retrofit system maintains the aesthetic appeal of a metal roof, which may be a crucial consideration for certain building owners. 
• Long lifespan: Like a complete replacement, a metal panel retrofit system offers an extended service life, providing reliable protection for your building. 
• Addresses major roofing issues: Metal panel retrofit systems can effectively resolve significant roofing problems, such as leaks and deteriorated panels. 
• Less expensive than metal replacement: A metal panel retrofit is less labor intensive and typically more affordable than a complete removal and replacement, making it an attractive option for building owners seeking cost-effective solutions. 
• No need to expose the building to the elements: The retrofit process does not require removing the existing metal roof, meaning your building remains protected from weather conditions during installation. 

Cons of metal panel retrofit 

• Still one of the most expensive options: Although less costly than a complete removal and replacement, a metal panel retrofit can still be a significant investment. 
• Difficulty in installation on complex roofs: Roofs with numerous penetrations or complex designs may present challenges for the installation of a metal panel retrofit system. 
• Warranty limitations: Most warranties for metal panel retrofit systems cover only the metal finish, with some weathertight warranties available on the market but not universally offered. 
• No insulation or reflectivity improvement: A metal panel retrofit system may not provide significant improvements in insulation or reflectivity compared to the existing roof. 

A metal panel retrofit is a suitable option for commercial and industrial building owners who want to maintain the look of a metal roof while addressing major roofing issues. While this option may be more expensive than some alternatives, it offers a long-lasting solution that preserves the aesthetic appeal of your building’s metal roof. 

Membrane retrofit - An all-around solution 

For building owners looking for a versatile and reliable solution to address their aging metal roof’s issues, a single-ply membrane retrofit might be the answer. This option involves installing layers of insulation to make a smooth roof surface and a high-performance membrane over the existing metal roof, providing an additional layer of protection that effectively solves most major roofing concerns while offering several other advantages. 

The membrane retrofit process requires a thorough evaluation of the existing roof, proper membrane selection and precise installation to ensure a successful outcome. 

Sentry Roofing, Inc. can assist you in making the right choices and provide professional installation services for your membrane retrofit project. 

Pros of membrane retrofit 

• Solves most major roofing issues: Membrane retrofit systems are designed to address various roofing problems, including leaks, rust and failing flashings. 

• Comprehensive warranty coverage: Membrane retrofit warranties typically cover roof leaks and are often no-dollar-limit warranties, providing peace of mind for building owners. 
• Additional insulation options: The installation of a membrane retrofit system adds insulation to your roof which improves your building’s energy efficiency. 
• Increased reflectivity and emissivity: Selecting a white membrane for your retrofit system can enhance your roof’s reflectivity and emissivity, potentially reducing energy consumption and cooling costs. 
• No need to expose the building to the elements: The retrofit process allows your building to remain protected from weather conditions during installation. 
• Effectively seals existing roof penetrations: Membrane retrofit systems excel at sealing existing roof penetrations, providing a watertight solution for your building. 

Cons of membrane retrofit 

• Higher cost than coating: While a membrane retrofit is typically more affordable than metal panel retrofit or replacement, it is still more expensive than a simple coating solution. 
• Potential change in aesthetics for some building owners: If the appearance of a metal roof is essential for your building, a membrane retrofit may alter the aesthetics, which could be a concern for some owners. 

A membrane retrofit is a flexible and effective solution for addressing the challenges of an aging metal roof. Although the cost may be higher than a coating, the benefits of a membrane retrofit, such as comprehensive warranty coverage, insulation improvements and increased reflectivity, make it a worthwhile investment for many commercial and industrial building owners. 

Making the right choice for your metal roof 

As a commercial and industrial building owner, addressing the issues associated with an aging metal roof is a critical concern. In this blog post, we have provided an in-depth analysis of the four main metal roofing options available to you: coating, remove and replace, metal panel retrofit and membrane retrofit. 

Each option comes with its unique advantages and drawbacks and selecting the right solution for your building’s specific needs is paramount. 

At Sentry Roofing, Inc., we believe that metal retrofitting, particularly membrane retrofit systems, offers an excellent balance of cost-effectiveness, performance and long-lasting protection for aging metal roofs. While it may not be the least expensive option, the comprehensive warranty coverage, improved insulation and increased reflectivity make it a sound investment for many commercial and industrial building owners. 

Ultimately, the decision of which option to choose for your aging metal roof lies with you, the building owner. By considering the information provided in this blog post, along with the advice of a reliable commercial roofing contractor like Sentry Roofing, Inc., you can confidently make an informed decision that will ensure the long-term protection and performance of your metal roof. 

Original article source: Sentry Roofing