The Cool Facts About Flame Spread Rating & TimberTech Decking

August 20, 2020

Your family’s safety has always been important to you — and we know it’s a major factor when you’re considering building materials for your outdoor living space. If you’re looking for a backyard build that combines all the nature-inspired beauty of traditional wood with the leading materials science of composite decking, look no further than TimberTech.

Because your deck should fight moisture and flame spread alike.

What Is ‘Flame Spread Rating’?

If you’re wondering how flame spread can be measured in the first place, you’re not alone.

Today’s building materials are tested, rated, and classified by the International Building Code (IBC) as developed by the International Code Council (ICC). In short, the ICC tests building materials by burning them under controlled conditions and measuring the speed and extent of flame spread.

The IBC recognizes the American Society for Testing and Materials’ (ASTM) benchmark, Standard Test Method for Surface Burning Characteristics of Building Materials, or ASTM E84. Flame Spread results range on an index from Class A (the best) to Class C.

What to Know

  • Flame Spread Rating Index = A numerical reference that measures how fast and far a flame spreads during a 10-minute test.
  • Class A = Flame Spread Index of 25 or less; the best possible rating, awarded to fire-retardant building products, like concrete.

What Is WUI Compliance?

WUI stands for “Wildlife Urban Interface” and was adopted by the California Building Commission a decade and a half ago. WUI designates areas that are within or adjacent to communities deemed “at-risk” for wildfires. WUI-compliant building products, therefore, mean those below a certain threshold for flame spread.

Some jurisdictions designated as Wildland Urban Interface (WUI) areas, especially in California, Colorado, and Nevada, actually require that decking products meet the Class A Flame spread rating.

One of those products? The TimberTech AZEK® Vintage Collection®.

The Vintage Collection

TimberTech AZEK Vintage Mahogany Decking Class A Flame Spread Rating

Leading Tech

The most advanced synthetic material technology, without the use of wood particles in the core or cap.

TimberTech AZEK Vintage Weathered Teak with flame spread rating rooftop deck in Chicago

Superior Performance

Backed by industry-leading warranties: A 50-Year Limited Fade & Stain Warranty and Lifetime Limited Product Warranty.

High Flame Spread Rating from Fully Synthetic Material

Fully Synthetic Material

Engineered to not only protect against invasion from moisture, insects, and other harmful agents but to curb flame spread.

How Does TimberTech Prioritize Fire Safety?

Put simply? Because Better Tech Means Better Deck. We combine sustainable manufacturing processes with innovative materials science so that your composite deck boards can keep their shape, hue, and beauty — even when faced with harsh conditions.

Why TimberTech Beats Wood on Flame Spread Rating

  • Protective polymer capping: Our decking portfolio includes 3- and 4-sided capped deck boards, and our capping is 100% synthetic. No organic material means no ready-made fuel for fire.
  • Majority-synthetic board cores: Our capped composite decking lines (TimberTech PRO® and TimberTech EDGE®) feature up to 80% recycled content, and capped polymer TimberTech AZEK decking boasts up to 54% recycled content — that’s post-consumer polymers and plastics. Instead of letting those materials fill landfills, we repurpose them to strengthen and protect your deck boards. Again, cutting down on organic material means limiting a fire’s chance to spread quickly.

WUI-Compliant TimberTech Products

TimberTech AZEK WUI-Compliant Decking

We know protecting your family and your home is always top-of-mind. With WUI-compliant composite decking, you can feel good about their safety, and about your role in protecting the planet.

Ready to see and feel better tech for yourself?

See & Feel the TimberTech Advantage

Our capped polymer and capped composite decking lines combine recycled material with all the beauty of traditional wood.

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