Access the latest method for assessing the fire spread traits of exterior wall assemblies constructed of combustible materials or components.
NFPA 285, Standard Fire Test Method for Evaluation of Fire Propagation Characteristics of Exterior Wall Assemblies Containing Combustible Components, outlines a test method for determining the flame spread resistant properties of these materials when exposed to interior fires.
The purpose of this standard is to provide a standardized fire test procedure for evaluating the suitability of exterior wall assemblies that are constructed using combustible materials or that incorporate combustible components for installation on buildings. It covers details for the test specimen—including how it must be mounted, the size of the specimen, and the position of it.
The 2025 edition of NFPA 285 features:
- A new Chapter 12 with guidance on an engineering analysis/judgment that may demonstrate how exterior wall assemblies that differ from a successfully tested wall assembly comply with NFPA 285
- A revised Annex B to reflect new guidance in Chapter 12
