Go beyond the surface of fluid-applied roofing

By Emma Peterson. 

Learn why more professionals are treating fluid-applied roofing as membranes.  

Fluid-applied roof systems are exactly what they sound like – roofing systems that are applied in a liquid (fluid) form. Once they are installed, they then cure into a seamless, waterproof barrier across the roof substrate. Made from a variety of materials, such as polyurethanes, acrylics, rubberized asphalts and acrylics, they have grown popular because they don't have weak points in the form of seams found in traditional sheet membranes.  

These fluid-applied systems have often been used as coatings. Roof coatings are typically installed in thin layers with the purpose of “protect[ing] against UV exposure, improv[ing] reflectivity and/or provid[ing] limited waterproofing.” Traditionally, this is the only role that fluid-applied has filled in roofing. But there is a shifting sentiment in the industry that fluid-applied systems can also be installed as full-on membranes. Membranes, in contrast to coatings, are considered the primary waterproofing system on a roof and must handle movement, all types of weather and long-term use.  

What is driving this change in perspective? Developments in the technology behind fluid-applied systems that make them more durable and higher performance! These include:  

• Seamless finish: As we mentioned, fluid-applied roofing avoids seams as it cures into one continuous layer. This avoids one of the most common sources of roof failure. 
• Easy installation: Fluid-applied systems do not require complex installation steps like mechanical fastening or heat welding; this lowers safety risks and labor requirement.  
• Long-term sustainability: Many fluid-applied products are low-VOC and can be re-coated at the end of their service life, rather than completely torn off. This makes them both more environmentally sustainable and financially affordable. 
• Monolithic coverage: The same continuous coverage that avoids seams also makes it easy to apply around penetrations, irregular surfaces and complex roof details. Further, these systems have no layered assemblies that could separate or delaminate. 

These are just some of the many reasons the industry is shifting towards thinking about fluid-applied systems as more than just coating options. To be clear, when we think about fluid-applied as a membrane, rather than just a coating, it is important to note that the systems must be installed accordingly. Western Colloid explained:  

When fluid-applied systems are treated only as coatings, they’re often under-specified or applied too thinly. But when they’re treated as membranes, they’re designed and tested to meet — or even exceed — the performance standards of traditional systems like TPO, PVC, EPDM or modified bitumen. 

At the end of the day, as roofing technology and products evolve, it is natural to discover new ways to use products and systems.  

Learn more about using fluid-applied roof systems as membranes.