What is a Thermal Barrier?
A thermal barrier, or heat barrier insulation, is an essential component when using spray foam insulation. It acts as a shield, protecting against fire and slowing the movement of heat between insulation and living spaces. Materials like drywall or intumescent coatings (special fire-resistant coatings) are commonly used as thermal barriers.
A thermal barrier provides more time for safe evacuation by slowing the spread of fire. It is not only vital for fire protection but also plays a significant role in improving your home's energy efficiency and comfort.
In this article, you’ll learn more about why thermal barriers are important, the materials used, and how to apply them in DIY spray foam insulation projects.
Why Are Thermal Barriers Important in Spray Foam Insulation?
Thermal barriers are important because they serve as a fire-resistant layer, helping to contain flames and minimize heat transfer, which is crucial for maintaining safety and consistent indoor temperatures. Materials like drywall or intumescent coatings create this protective layer, increasing the overall safety of your home. When using spray foam insulation, a thermal barrier is necessary to protect it from fire hazards by delaying the ignition of the material, giving extra time for evacuation.
In high-risk areas, such as those close to living spaces, thermal barriers are essential for minimizing the fire hazard. According to building regulations, walls, ceilings, and roofs containing spray foam must be protected with a thermal barrier to comply with safety codes. Beyond fire protection, thermal barriers help maintain a consistent indoor temperature, improving energy efficiency in both hot and cold weather.
What is a 15 Minute Thermal Barrier?
The 15-minute thermal barrier is designed specifically to delay fire spread, giving occupants 15 minutes to safely evacuate their homes. Common examples include 1/2-inch gypsum board or special fire-resistant coatings. These barriers help control fire and increase safety by preventing the spray foam temperature from reaching 250°F for 15 minutes. They are mandated by building codes such as the IRC.
What Types of Materials Are Used as Thermal Barriers?
Here, 4 materials used as thermal barriers are:
- Gypsum Board (Drywall)
- Intumescent Coatings
- Plywood
- Cementitious Coatings
When Do You Need a Thermal Barrier for Your DIY Spray Foam Project?
You need a thermal barrier for your DIY spray foam project when the insulation is close to living spaces. For best results, use high-quality spray foam insulation and install a thermal barrier when necessary. Thermal barrier insulation helps slow the spread of fire and provides extra time for escape in an emergency. Installing a thermal barrier for spray foam is necessary for compliance with building regulations.
What are the Building Code Requirements for a Thermal Barrier?
The building code mandates a thermal barrier to separate spray foam insulation from living spaces and ensure fire safety. According to the International Residential Code (IRC), this barrier must provide at least 15 minutes of protection and be made of ½-inch gypsum board or similar materials.
What Are the Common Areas That Require a Thermal Barrier?
Thermal barriers are required in areas where spray foam insulation is exposed to living spaces or where there is a fire hazard. These areas require heat barriers and fire-resistant coatings to ensure safety and compliance with building regulations. Common areas requiring thermal barriers are:
- Exterior walls
- Ceilings
- Basements used for storage or living
- Attic spaces
How to Install a Thermal Barrier with Spray Foam Insulation?
To install a thermal barrier with spray foam insulation, apply thermal coat spray foam over the insulation layer to provide fire resistance and additional insulation. This barrier ensures safety by separating the spray foam from living spaces and preventing rapid heat transfer in the event of a fire. Drywall or an intumescent sheeting acts as this barrier. Remember that you can add more after the application has completed expansion. For more information, see our Essential Guide to Spray Foam Insulation.
Frequently Asked Questions
Is Plywood a Thermal Barrier?
Yes, plywood can act as a thermal barrier because it is a fire-retardant material. Plywood is, therefore, widely used as a thermal barrier between living spaces and insulation.
Is Drywall a Thermal Barrier?
Yes, drywall is commonly used as a thermal barrier, especially in combination with spray foam insulation. During a fire, it delays the ignition of the foam, allowing up to 15 minutes for safe evacuation. This makes it a fire-retardant material in homes.
Do I Need a Thermal Barrier with Spray Foam Insulation?
Yes, using a thermal barrier with spray foam insulation is important for fire protection, especially in areas close to living spaces. Thermal barriers provide a protective layer that slows down the spread of heat in case of a fire. For more details on using thermal barriers with spray foam, see our Spray Foam Insulation Tips.