Understanding Structure Ignition Vulnerabilities Using Mock-up Sections of Attached Wood Fencing Assemblies

Firebrand production from structure combustion becomes a key factor in the magnitude of how quickly a large outdoor fire may spread. Post-fire disaster investigations suggest that attached building components, such as wood fencing assemblies are known to be prone to ignition in these fires, and may provide pathways to structure ignition. Here, a comparison of ignition results from full-scale fencing assembly experiments conducted using a full-scale wind tunnel facility, to mock-ups of full-scale fencing assemblies using the recently developed experimental capability at the National Research Institute of Fire and Disaster (NRIFD) are discussed. In both experimental facilities, the fencing assemblies were exposed to firebrand showers using custom built continuous-feed firebrand generators with size and mass distributions similar to those generated from structure combustion. Similar ignition behaviors were observed between the full-scale fencing assemblies and the mock-up of full-scale fencing assemblies. Additional experiments are required for other fencing assembly types to further verify these important findings.