Is Hardie Board Flammable? Discover the Truth about its Fire Resistance

Is Hardie Board Flammable?

Hardie Board, also known as fiber cement siding, is a popular choice among homeowners for its durability and low maintenance. One important question that many people have when considering this type of siding is whether or not it is flammable. In this article, we will explore the flammability of Hardie Board and provide you with all the necessary information.

Flammability refers to the ability of a material to catch fire and sustain combustion. Given that home fires can be devastating, it’s essential to understand the fire resistance properties of building materials, including siding.

Is Hardie Board Flammable? Discover the Truth about its Fire Resistance


What is Hardie Board?

Hardie Board is a composite material made from a blend of cement, sand, and cellulose fibers. The resulting product is a durable and sturdy siding option that can mimic the appearance of wood, stucco, or other materials.

Being a composite, Hardie Board exhibits excellent fire-resistant properties that set it apart from other traditional sidings such as vinyl or wood. Let’s dive deeper into why this material is considered to be non-flammable and how it compares to other options.

Is Hardie Board Flammable? Discover the Truth about its Fire Resistance


The Fire Resistance of Hardie Board

Hardie Board has gained popularity over the years due to its exceptional fire resistance. While it is important to note that no material is entirely fireproof, Hardie Board comes very close to being so.

Hardie Board is classified as a non-combustible material, which means it does not contribute to the spread of fire. Its primary components, cement and sand, are naturally fire-resistant, reducing the risk of ignition. The addition of cellulose fibers further enhances its fire resistance.

Additionally, Hardie Board is designed with multiple layers, increasing its durability and resistance to fire. The presence of numerous layers makes it challenging for flames to penetrate the material.

Unlike wood siding, which is highly flammable and can contribute to the rapid spread of fire, Hardie Board provides added safety and peace of mind to homeowners. It has a Class A fire rating, the highest possible rating for fire resistance.

How Does Hardie Board Compare to Other Siding Options?

Siding Material Flammability
Hardie Board (Fiber Cement) Non-combustible
Vinyl Flammable
Wood Highly flammable
Stucco Non-combustible

As shown in the table, Hardie Board outperforms other common siding materials when it comes to fire resistance. Vinyl and wood sidings are flammable, making them more susceptible to catching fire and spreading it throughout the building.

On the other hand, stucco is also non-combustible like Hardie Board, but it does not possess the same level of durability. Unlike stucco, fiber cement siding does not crack easily, ensuring prolonged fire resistance.

Additional Benefits of Hardie Board

Aside from its exceptional fire resistance, Hardie Board offers several other advantages that make it an ideal choice for homeowners:

  • Durability: Hardie Board is resistant to rot, pests, and damage caused by harsh weather conditions.
  • Low Maintenance: It requires minimal upkeep, reducing the need for frequent repairs or replacements.
  • Longevity: The lifespan of Hardie Board is typically longer than other siding materials.
  • Style Options: It is available in various colors, textures, and styles, allowing homeowners to customize their exteriors.

Overall, Hardie Board provides a combination of fire resistance, durability, and aesthetic appeal that many homeowners appreciate.

Frequently Asked Questions For Is Hardie Board Flammable? Discover The Truth About Its Fire Resistance

Is Hardie Board Flammable?

No, Hardie Board is not flammable. It is made of cement, wood fibers, and additives that make it highly fire-resistant.

Can Hardie Board Catch Fire?

Hardie Board is highly fire-resistant and does not easily catch fire. It has a Class A fire rating, which is the highest level of fire resistance.

What Happens If Hardie Board Is Exposed To Flames?

If Hardie Board is exposed to flames, it will not ignite or release toxic fumes. It will char on the surface, but it will not contribute to the spread of fire.

Is Hardie Board Fireproof?

Hardie Board is not technically fireproof, but it is highly fire-resistant. It can withstand high temperatures and provides an extra layer of protection against fire hazards.


Hardie Board, also known as fiber cement siding, is a non-combustible material that offers excellent fire resistance. With its composition and multiple layers, it significantly reduces the risk of ignition and the spread of fire. Comparatively, it outperforms other siding options like vinyl and wood, which are flammable. In addition to its fire resistance, Hardie Board boasts durability, low maintenance, and various style options. If you are looking for a safe and long-lasting siding material, Hardie Board is a great choice.

Updated: December 31, 2023 — 5:12 pm