(The information below is excerpted from the Significant Changes to the 2012 International Codes series.)
The use of 1/2-inch wood structural panels installed on the walking surface side of a floor assembly is now permitted as an alternative to the thermal barrier typically required where foam plastic insulation is installed within a floor assembly. The thermal barrier typically required where foam plastic insulation is installed beneath a walking surface must not only be an adequate barrier to protect the foam plastic but must also be durable enough to withstand the load and wear-and-tear that is needed for the floor. The new allowance is consistent with the minimum protection required for attics and crawl spaces and should eliminate confusion about what level of protection is needed for floor assemblies containing foam insulation, such as those where structural insulated panels are used.
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