Is Spray Foam Insulation Flammable?

The safety and effectiveness of insulation materials are paramount concerns for homeowners and builders. Among various insulation options, spray foam insulation has garnered attention due to its exceptional insulating properties. 

 However, a pertinent question arises: Is spray foam insulation flammable? This blog delves into the crucial topic of spray foam insulation’s flammability, including the role of fireproof paint. By examining different perspectives and expert insights, we aim to comprehensively understand the material’s fire risk and its implications for residential and commercial applications.

Is Spray Foam Insulation Flammable


Spray foam insulation is a high-quality, durable, and energy-efficient insulation and air barrier solution used in residential and commercial structures. It is created on-site using specialized equipment, typically polyurethane foam that expands upon application. 

Today, spray foam insulation contributes to enhanced comfort, reduced energy consumption, and improved building science by serving as a thermal and sound barrier while safeguarding against air leakage and providing continuous insulation.

Flammability Concerns

Spray foam insulation, like all foam plastic materials, is indeed flammable. It can potentially catch fire and combust when exposed to sufficient heat sources. Its flammability is primarily attributed to the chemical composition of polyurethane foam, a common material used in spray foam insulation. 

Polyurethane foam contains hydrocarbons, which are compounds made up of hydrogen and carbon atoms. These hydrocarbons are inherently combustible, and when exposed to heat or flames, they can undergo combustion reactions, releasing heat, light, and potentially harmful combustion byproducts such as smoke and toxic gasses. 

As a result, while spray foam insulation offers valuable insulation properties, it’s essential to be aware of its flammability characteristics and take appropriate fire safety precautions in its installation and use.

Fire Ratings and Resistance

Fire ratings, such as the “class 1 hour fire rating,” indicate the ability of a material or assembly to withstand exposure to standardized fires for a specified duration. These ratings classify materials and components’ performance when fire or heat is subjected. For example, a “class 1 hour fire rating” means the material can resist exposure to a standardized fire for one hour.

Fire-resistant treatments for materials like spray foam involve applying coatings, intumescent paints, or barriers that expand when exposed to heat, creating a protective layer that insulates against flames. 

These treatments slow combustion and heat transfer, providing additional time for occupants to evacuate and firefighters to respond. Combining fire-resistant treatments with proper installation practices enhances the safety of buildings and structures, reducing the potential impact of fires.

Safety Measures

Installing and using spray foam insulation requires careful safety measures. Here are some key precautions:

Personal Protective Equipment (PPE): Wear appropriate PPE, including goggles, gloves, long-sleeved clothing, and respiratory protection, to minimize skin and inhalation exposure to chemicals.

Ventilation: Ensure proper ventilation during installation to dissipate fumes and avoid accumulation of volatile organic compounds (VOCs).

Evacuation: Inhabitants should vacate premises during installation, especially for 24 hours post-installation, due to potential off-gassing.

Professional Installation: Have trained professionals install the insulation, adhering to industry best practices and safety guidelines.

Fire Safety: Prevent ignition sources, as spray foam is flammable. Apply fire-resistant coatings to mitigate flammability risks.

Safe Handling of Chemicals: Understand the chemicals used in spray foam and follow proper handling and storage protocols.

Safety Recommendations: Refer to safety resources provided by organizations like EPA and CPSC to understand risks and precautions.

Cost and Value

Spray foam insulation offers several benefits but generally comes at a higher initial cost than other insulation options like fiberglass. Key points to consider:

Energy Efficiency: Spray foam provides superior insulation and air sealing, saving energy and reducing heating/cooling bills.

Cost Comparison: Spray foam insulation costs more upfront, but its long-term energy savings can offset this cost over time.

Moisture and Air Barrier: Spray foam acts as a moisture and air barrier, preventing mold growth and drafts.

Durability: Properly installed spray foam insulation can last for decades without deterioration.

Installation Complexity: Spray foam requires professional installation due to its application technique.

Cost Factors: The cost of spray foam insulation depends on factors like insulation type (open-cell or closed-cell), thickness, and area to be insulated.


In conclusion, the flammability of spray foam insulation raises important considerations for homeowners and builders alike. Spray foam is indeed flammable due to its foam-plastic nature. However, a “class 1 hour fire rating” indicates its ability to withstand exposure to standardized fire conditions for a specified duration. 

While spray foam insulation can provide benefits such as enhanced insulation and air sealing, it’s essential to balance these benefits with the possible risks, particularly regarding fire safety. Don’t compromise safety. Contact Foam Insulation Solution at (888) 616-8704 to learn about spray foam insulation’s fire risks and ensure a secure environment for your family.