Wildland Urban Interface Codes in the USA: Comparison Between the Codes From the International Code Council and the State of California

Two organizations in the United States have developed codes to protect against the hazards associated with wildfires: the International Code Council (ICC; a private not-for-profit organization) and the state of California. Both codes contain strict requirements that, when put into effect, do significantly improve fire safety. The ICC code (IWUIC) has been adopted (either as issued or with amendments) by several states in the USA while the California code (CA Chapter 7A) applies only in that state. There are many similarities between both sets of codes but there are also some clear differences. The most important difference is that CA Chapter 7A allows wood that has not been treated with fire retardants (untreated wood) to be used on decks and walls, while the IWUIC requires the use of materials with improved fire performance for those applications. On the other hand, there are also requirements in CA Chapter 7A that are more conducive to fire safety than the equivalent ones in the IWUIC. One example is the fact that CA Chapter 7A does not permit the use of coated wood materials, in view of the act that all wildland applications involve exterior use and that coatings on wood materials have been shown to be susceptible to suffer fire performance degradation when exposed to weather; IWUIC is silent on that issue, meaning that the use of coated wood materials is not prohibited. The two codes (in the USA only) will be compared and contrasted in this work with respect to delivering improved fire safety.