LETTER TO THE EDITOR

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Updated: August 4, 2011 4:20PM

Industry spokesman challenges statements about vinyl siding as ‘high fire-spread material’

There are several inaccuracies in the article “South Elgin poised to water down its fire sprinkler rules,” published Thursday — including the statements by Steve Super, director of community development for the village of South Elgin, that vinyl siding is a “high fire-spread material” and an “oil-based product.” Both of these statements are incorrect.

It is a misperception that vinyl siding is an oil-based product. Vinyl siding is actually made of natural gas and salt. Polyvinyl chloride, more commonly known as PVC or vinyl, is unique among plastics in that it does contain chlorine (which it gets from the salt), which results in vinyl siding being inherently flame-retardant.

Moreover, because of the unusually large amount of oxygen required for vinyl siding to burn and stay burning, it will not independently sustain combustion in air with a normal concentration of oxygen. Vinyl siding does not readily stay burning on its own; unless it is involved in a fire fueled by other materials, it tends to self-extinguish.

Not only is vinyl siding not a “high fire-spread material,” its inherent flame-retardant characteristics significantly reduce its contribution to fire spread, especially in comparison with other common building materials. Vinyl siding is typically given a flame spread index rating of 25 or less, which puts it in the category with the highest resistance to flame spread. Vinyl siding is a specified component in many fire-rated assemblies recognized by both the International Building Code and International Residential Code.

In testing required for combustible wall coverings under the International Building Code, vinyl siding typically qualifies for use at the closest fire separation distances allowed under the code. The National Fire Protection Association statistics show that only a very small percentage of home structure fires originate on the exterior wall surface (fewer than 2 percent); but when they do, burning of vinyl siding does not significantly contribute to the spread of the fire.

Matthew Dobson

Director, Code and Regulatory

Vinyl Siding Institute