Recent progress on test evidence, standardization and design of protection for exterior openings

Any opening in the exterior of structures are critical when exposed to fire. Windows and doors may be open, ventilation openings may be unprotected, wall cladding and roof tiles may allow flames or embers to enter cavities. Gaps may have developed over time and allow embers to settle in crevices or cavities in the structure. In fact, rarely does initial fire penetration occur right through cladding, sheets, insulation or solid walls. Penetration is most often related to openings, weak joints or cracks. There is no doubt these weak points to fire spread in construction or indoor are crucial to the outcome of exterior fire exposure whether caused by wildfire or fire in outdoor trash or neighbouring buildings. Therefore, this has been addressed by authorities, standardization bodies and industry world-wide and much progress have been made during the last decade. This paper provide overview on new standards, on codes and on various pass/fail criteria set by code or classification standards. The paper describes how new designs of fire resistant ventilating facades and roofs apply dedicated cavity fire barriers and how new standard test methods helps to improve performances. A number of different fire scenarios that elements in vented facades/constructions can be exposed to have been studied. New test standards have been developed for the last few years and are explained. Finally, this paper evaluate how different fire stop products perform in different fire scenarios and which test standards are applicable