HomeOutdoor Living BlogFlame Spread Ratings, Ignition Resistance & WUI Compliance: What Homeowners Need to Know

Flame Spread Ratings, Ignition Resistance & WUI Compliance: What Homeowners Need to Know

April 3, 2024
Outdoor living room on a light brown deck in the desert

When it comes to decking for your home, fire safety is crucial, especially in wildfire-prone areas. Understanding flame spread ratings and choosing materials with an Ignition Resistant designation, a Class A Flame Spread Rating, and/or WUI Compliance can help protect your home and loved ones. With TimberTech Advanced PVC Decking, you can enjoy your outdoor space knowing that you’ve made a smart investment in safety and durability. Let’s take a closer look at flame spread ratings and learn why they matter as you choose a decking material for your project.

Why you should choose TimberTech’s fire-resistant decking

"Best Choice for Fire Zones" badge
Class A badge, reads, "A | Class A Flame Spread Rating | ASTM E84"
Ignition Resistant badge, a graphic of a match with a slash through it is in the middle, the text reads, "Ignition Resistant | ASTM E2768"
WUI Compliant badge, reads, "WUI Compliant | Meets requirements for Wildlife Urban Interface | ASTM D7032 / E84"

Here’s a quick preview of just some of the benefits TimberTech Advanced PVC Decking offers:

  • Top-rated fire resistance With collections featuring an Ignition Resistant designation, a Class A Flame Spread Rating (the best available), and/or WUI Compliance.
  • Code compliance Municipalities in some areas require not only WUI Compliance but decking with a Class A Flame Spread Rating.
  • Low maintenance TimberTech’s fire resistance is inherent to the material itself.
  • Durability Our products are designed to withstand the elements, including harsh weather conditions and UV exposure, ensuring long-lasting performance and protection.
  • Authentic wood looks With a wide range of colors, textures, and finishes, our decking allows you to create an outdoor oasis that complements your home’s design.
  • Peace of mind You can enjoy your outdoor space with confidence, knowing that you’ve taken proactive steps to help protect your deck against fire hazards.

Understanding Flame Spread Ratings

Flame spread ratings are based on the measure of how quickly and how far flames travel across the surface of a material. This indicates a material’s resistance to fire and its potential to contribute to the spread of flames. Ratings range from Class A (0-25) to Class C (76-200). A Class A Flame Spread Rating indicates superior fire resistance, meaning the material is highly effective at inhibiting flame spread. Here’s what the ratings mean for your deck:

Flame background
Class A badge, reads, "A | Class A Flame Spread Rating | ASTM E84"

Class A Flame Spread Rating

This is the best rating available, and indicates a material is in the highest range of resistance to flames. This means that in a fire, flames will spread slower across the deck surface. Class A Flame Spread Rated decking will resist catching fire and won’t readily contribute to the spread of flames.

Class B & C Flame Spread Ratings

These ratings indicate materials spread flames more readily. Traditional wood and composite decking fall into these categories, indicating they pose a greater fire risk.

What Ignition Resistance Means in California

As growing wildfire threats endanger lives and property, California is working to protect both. Our Advanced PVC Vintage and Landmark Collections have been designated as ignition-resistant, the second highest level of recognition next only to non-combustible materials. The crucial time a flame or ember first touches a material is when ignition resistance comes into play. Ignition-resistant materials resist catching fire or burning easily, and that may slow the spread of flames.

What does a Class A Flame Spread Rating — and Ignition Resistance — mean for homeowners?

Two chairs and an outdoor couch face each other, a coffee table separates the furniture

Ignition-resistant, Class A Flame Spread Rated decking, like our Vintage and Landmark Collections, can help provide better protection for your home against fire incidents. Materials with this rating are more fire resistant and won’t spread fire as quickly as materials in lower classes. This could help contain the fire and prevent it from rapidly spreading to other areas.

Resists igniting Ignition-resistant decking is less likely to catch fire compared to traditional wood and composite decking.  

Slower flame spread If a fire starts, it won’t spread as quickly. This could help contain the fire and prevent it from rapidly spreading to other areas.

Increased Combustion Resistance Class A-rated decking is more likely to have a slower rate of burning, reducing the risk of the fire becoming uncontrollable or causing extensive damage.

Enhanced safety In regions like California, where wildfires are a serious concern, fire-resistant decking is crucial to help safeguard your home. By choosing materials with this rating, you’re adding an extra layer of protection against the threat of fire.

Reduced risk In the event of a fire, these materials are more likely to resist fire and slow the spread of flames compared to traditional wood and composite decking materials. This may give you valuable time to help prevent more extensive damage. 

Code compliance Some areas of the country require decking to have a Class A Flame Spread Rating for WUI Compliance.

WUI Compliance Explained

Wildland Urban Interface refers to zones where houses and areas prone to wildfires meet and where wildfires can easily jump to structures. It’s not just a western state issue; over 60,000 communities in the U.S. are at risk for WUI fires. Different sets of rules and regulations exist for WUI fire safety in different jurisdictions.* Local building codes in WUI zones require fire-resistant materials for construction projects, including decks. In general, these materials resist flame spread and catching fire due to flying embers.

TimberTech’s Advanced PVC Decking and TimberTech Porch, as well as the Composite Reserve Collection for WUI areas (special order only), meet WUI compliance standards,* ensuring your deck adheres to regulations and offers an extra layer of protection. By choosing WUI compliant decking, you’re not only prioritizing safety for your home, you’re also contributing to a fire-resistant community that can help mitigate the spread of wildfires.

Building a Safe and Beautiful Deck

Safety shouldn’t compromise aesthetics. TimberTech offers a variety of collections featuring an Ignition Resistant designation, a Class A Flame Spread Rating, and/or WUI Compliance in a variety of colors and styles to match your vision, so you can build a beautiful, low-maintenance deck that prioritizes both safety and style. Explore our range of colors and textures to find the right fire-resistant collection for your outdoor space.

Additional Fire Safety Tips

No matter which decking you choose, remember these general safety practices:

  • Request information from your local Fire Marshal’s office on local fire code ordinances and recommendations.
  • Keep your deck and surrounding areas clear of debris like leaves, branches, or flammable materials.
  • Regularly clean your grill and dispose of grease properly.
  • Maintain a safe distance between fire pits or grills and the deck.
  • Have working smoke detectors and fire extinguishers readily accessible near your deck.
  • Have a fire evacuation plan in place for your family.

By choosing TimberTech Advanced PVC and following these safety tips, you can help create a beautiful, more fire-resistant outdoor space for your family to enjoy. 

*Check with your local building code department or local Fire Marshall for more guidance.

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