When it comes to fire safety in structures, two critical components come into play—thermal barriers and ignition barriers. Each is a critical aspect in the design and construction of any building. Understanding the distinctions between both barriers is key to ensuring the appropriate level of protection for a building, from homes to offices and beyond. Not only do these barriers make buildings safer, but they also ensure the designs are code-compliant on a regular basis.
The risk of fire is a constant threat that can cause devastating loss of life and property. Ensuring the right fire safety measures are in place can make the difference between a minor incident and a catastrophic event. So what is the difference between thermal and ignition barriers? Let’s examine what sets these materials apart so you can properly use them both in any building.
Discussing Thermal Barriers
A more detailed understanding of thermal barriers requires a closer look at their structure and function. A thermal barrier essentially acts as a shield, preventing the foam insulation from reaching a temperature that could lead to ignition. It slows down the transfer of heat and delays the temperature increase of the foam during a fire, thereby reducing the risk of fire spreading by direct flame impingement.
However, although thermal barriers are shields, their protection is temporary. Using thermal barriers in construction does not make a building’s structure impenetrable by fire, but it does delay damage and the spread of flames significantly. With coatings ranging from 15-minute protection to an hour or more, applying a thermal barrier gives building occupants extra time to react during emergencies.
Protection with thermal barriers involves limiting the heat transfer from one side of the barrier to the other. In simplest terms, a thermal barrier shields the foam from the interior spaces in the event of a fire.
The materials frequently used for thermal barriers, such as gypsum and specially treated plywood, are common because of their fire-resistant properties. Thankfully, modern thermal barrier technology continues to help professionals protect buildings in many different ways. At Flame Seal, our TB-Pro thermal barrier is an intumescent material that will instantly make insulation less susceptible to fire damage upon application. Thermal barriers are effective on their own, but let’s take a closer look at why ignition barriers are essential for safety, too.
Evaluating Ignition Barriers
On the other hand, an ignition barrier is a material or system of materials that provides protection by delaying the ignition and subsequent spread of fire to the foam. As you can see, the confusion between ignition and thermal barriers is understandable. Ignition barriers, while somewhat similar, serve a slightly different purpose than their thermal counterparts.
Simply put, a thermal barrier is a material that separates insulation and the interior of a room, whereas an ignition barrier is applied directly to the insulation. The primary purpose of an ignition barrier is to prevent a small fire, such as a match or a shorted electrical wire, from getting to the foam insulation too quickly, thereby stopping it from becoming a large fire. Again, these materials don’t make insulation impenetrable to fire, but it does maximize durability, slowing down the flames temporarily.
Ignition barriers are typically installed in attics or crawl spaces where the foam insulation might be exposed. These materials are not necessarily fireproof but are durable enough to withstand exposure to fire for a longer period of time than other materials. Our spray foam ignition barriers at Flame Seal are intumescent coatings that will help you completely conceal foam plastic insulation with a defensive layer against direct flame exposure.
Testing for Compliance
Choosing the right thermal and ignition barriers requires understanding whether those barriers meet the codes relevant to your project. These primarily relate to the IBC, IRC, and NFPA codes. For instance, the aforementioned TB-Pro from Flame Seal is carefully designed and tested to meet the requirements of the E84 Class A, IBC 2603.9, IRC 302.9.4, and more.
While thermal and ignition barriers serve similar purposes, they don’t always meet the same codes and regulations. That said, both barriers must undergo testing to meet the current building codes and fire safety standards. In comparison, the FS-IB ignition barrier from Flame Seal passes the AC 377 Appendix X test, and you can use it to meet IBC and IRC requirements. Only choose a thermal or ignition barrier when you know exactly what kind of testing the manufacturers use when creating it.
Applying Each Barrier
Now that you know the difference between thermal and ignition barriers, it’s crucial to know how they work together to keep buildings safe and compliant. In the wider context of building design, both thermal and ignition barriers play crucial roles in ensuring safety—but they are not interchangeable.
The materials used in these barriers serve a dual purpose, they provide the necessary insulation for energy efficiency, while also acting as a line of defense against fire. The choice of materials can greatly influence the fire resistance of a structure.
For instance, using gypsum as a thermal barrier increases the fire rating of a wall assembly, but accurate installation is paramount. Apply each barrier to meet relevant fire safety standards and building codes so the barriers can do their jobs successfully during emergencies. Similarly, the use of intumescent coatings as ignition barriers can improve the thermal performance of the building when properly applied by trained experts.
Use Your New Knowledge Now
Thermal and ignition barriers are more than just passive fire protection measures. They are integral components of a building’s overall design and construction, ensuring both energy efficiency and fire safety. As such, understanding the role of each material within these barriers is crucial in making informed decisions in building design and fire protection measures.
The choice between the two depends on the specific requirements of a building and the potential fire risks it faces. Thankfully, now that you know what sets thermal and ignition barriers apart, you can make an informed decision when working on any structure, whether commercial or residential. It is always recommended to consult with a fire safety professional when determining which type of barrier is most suitable for your needs. Put your new knowledge of this topic into action now if you’re working on a building that needs the benefits of thermal barriers and ignition barriers immediately.
