Is Spray Foam Insulation Flammable? Debunking the Myth

Spray foam insulation has gained popularity in recent years for its energy-efficient and cost-effective properties. Homeowners, however, often have concerns about fire safety when considering spray foam insulation for their homes. In this article, we will discuss whether spray foam insulation is flammable and what safety precautions should be taken.


Understanding Spray Foam Insulation

Spray foam insulation is a type of insulation material that is applied using a spray gun. It expands to fill and seal gaps, cracks, and cavities in walls, roofs, and other areas. The two main types of spray foam insulation are:

  1. Open-Cell Spray Foam: This type of foam is less dense and has a lower insulating value. Open-cell spray foam is permeable to moisture but offers excellent soundproofing properties.
  2. Closed-Cell Spray Foam: This foam is more dense, has a higher insulating value, and is impermeable to moisture. It provides superior insulation and acts as an effective vapor barrier.

Are Spray Foam Insulation Flammable?

Spray foam insulation, when properly installed and cured, is generally considered to be fire-resistant. The key factor that determines the flammability of spray foam insulation is the type of foam used.

1. Open-Cell Spray Foam: Open-cell spray foam is considered less fire-resistant compared to closed-cell spray foam. This is because open-cell foam contains a higher proportion of air and tends to be more combustible.

2. Closed-Cell Spray Foam: Closed-cell spray foam is more fire-resistant due to its dense structure. The trapped gases within the cells make it more difficult for heat and flames to spread through the material. Closed-cell spray foam can even provide additional structural integrity during a fire.

Fire Safety Precautions

While spray foam insulation is generally considered fire-resistant, it is still important to take necessary precautions to ensure safety. Here are some recommended fire safety measures:

  • Choose the Right Type: If fire safety is a major concern, opt for closed-cell spray foam insulation as it offers better fire resistance.
  • Proper Installation: Spray foam insulation should be installed by professionals who are trained in its application. Improper installation can increase the risk of fire hazards.
  • Fire-Resistant Coatings: Applying fire-resistant coatings over the spray foam insulation can provide an additional layer of protection in case of fire.
  • Clearances and Accessibility: Ensure that the spray foam insulation is not blocking any fire exits, electrical panels, or other areas that need to be easily accessible during an emergency.
  • Fire Safety Equipment: Install and maintain adequate fire safety equipment, including smoke detectors, fire extinguishers, and fire alarms, in your home.


Is Spray Foam Insulation Flammable?

Spray foam insulation is not flammable when properly installed. It meets industry safety standards and has a high fire resistance rating.

Does Spray Foam Insulation Release Toxic Fumes?

Spray foam insulation, when cured, does not release toxic fumes. It is made of non-toxic materials and is safe for residential and commercial use.

How Long Does Spray Foam Insulation Last?

Spray foam insulation can last a lifetime without losing its effectiveness. It is a durable insulation material that provides long-term energy savings.

Is Spray Foam Insulation Expensive?

Spray foam insulation may have a higher upfront cost compared to other insulation options, but its long-term energy savings make it cost-effective in the long run.


Spray foam insulation, when properly installed and cured, is generally considered to be fire-resistant. The closed-cell spray foam insulation provides better fire resistance compared to open-cell spray foam. However, it is important to take necessary fire safety precautions and follow the manufacturer’s guidelines to reduce the risk of fire hazards. By choosing the right type of spray foam insulation, ensuring proper installation, and observing fire safety measures, homeowners can enjoy the benefits of spray foam insulation while keeping their homes safe.

Updated: December 30, 2023 — 6:45 pm