Codes and standards
NFPA Impact: August 2018
By Shayne Mintz
By Shayne Mintz
This past June 14 marked the first anniversary of the Grenfell Tower fire in London, England, that blaze was one of the most tragic fires in the history of the modern United Kingdom. Seventy-two people died and more than 70 were injured.
Since the 1980s, innovative exterior wall facade systems have been developed to enhance building appearance and improve overall performance. In recent times, an increasing number of fast-moving fires involving combustible exterior cladding have occurred on high-rise buildings, including structures in Dubai, UAE, Shanghai, France, Korea and the U.S.
With an ever-aging building stock and the constant pursuit of innovative designs, there will be more and more of these types of retrofit exterior cladding applications found or being considered. As ever, vigilance is needed on the part of fire authorities to avoid falling victim to contractors or building owners who may or may not knowingly try to cut corners (and costs) to be more competitive.
In response, the National Fire Protection Association (NFPA) and the Fire Protection and Research Foundation (FPRF) have created a report titled “Fire Hazards of Exterior Wall Assemblies Containing Combustible Components”. To go even further the NFPA has established a website dedicated to sharing information that will increase awareness about these hazards and the codes that may address them. The latest research and reports that relate to these topics are posted at www.nfpa.org/exteriorwalls.
The research and the resources derived from the report are intended to help building owners and enforcement authorities assess the fire risk of existing high-rise buildings, as well as identify what fire test procedures apply when designing new buildings.
NFPA has also created a free, interactive tool to help navigate the code requirements that apply to exterior walls of high-rise buildings with combustible components. The tool, named the Exterior Facade Fire Evaluation & Comparison Tool (EFFECT), takes into account both existing and new structures and is intended to help building owners, facility managers, and authorities having jurisdiction (AHJ) identify, evaluate, and address hazards in high-rise buildings under retrofit that may have combustible exterior wall components.
The tool details how AHJs can conduct initial fire risk assessments and identify buildings that should have the highest priority for remediation and follow-up inspection. In addition the tool is also designed to help architects and engineers identify what fire test procedures are mandated when new wall systems or assemblies are being designed. In essence it serves as a means of decoding exterior wall requirements. It helps navigate the code requirements that apply to exterior walls containing combustible components and it also helps determine when those requirements require testing to whichever code or standard that applies to the local jurisdiction. In Canada the national model building code refers to CAN/ULC-S134, “Fire Test of Exterior Wall Assemblies” as the accepted test method.
There are however some limitations – it evaluates a building on its completed state and not on components of it. The tool does not address ‘temporary risks’ that may arise as a result of construction work or partial completion and occupation, and in the interest of fire and life safety it is considered to be conservative and widely applicable.
The methodology used in the EFFECT tool relies on a two-tier process. Tier 1, basically consists of a desktop study of a communities portfolio of building stock to establish a priority ranking for further assessment. Tier 2 undertakes a more detailed assessment based on the outcomes and ranking of tier 1. In this step such details consider the need for on-site inspections, review of ‘as built’ information, building maintenance records and evidence gathering that all component materials are tested as ‘assemblies’ and not as separate elements.
By going through a series of questions related to the exterior condition of a building; a profile of the building stock will emerge. The general outcomes from this profile will be, a building is compliant and no further action is required, mitigation or remediation measures are needed, or, a detailed assessment by a qualified team of facade and fire engineers is required.
Shayne Mintz has more than 35 years of experience in the fire service, having completed his career as chief of the Burlington Fire Department in Ontario. He is now the Canadian regional director for the National Fire Protection Association (NFPA). Contact Shayne at email@example.com, and follow him on Twitter at @ShayneMintz