What Does Class “B” Flame Spread Rating Mean?

September 29, 2016

A flame spread rating is a comparative number established through the Steiner Tunnel Test.

The way it works is that decking samples are exposed to a flame source to ignite them. The rate and distance the flame spreads is measured and assigned an index value based upon the results. So, the lower the rating, the longer it takes the decking to catch on fire and the slower it spreads—both good things!

The ratings are as follows:

A = 0-25

B = 26-75

C= 76-200

D = 201-500

E = OVER 500

All wood composite decking products are required to have a Class C or better flame spread rating. Fire regulations and codes continue to become more important in the building industry. TimberTech is committed to manufacturing products that are compliant with these requirements and safe for our customers.

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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