FE Analysis of a Modular Fireplace Fire with an Improperly Constructed Hearth Extension

Jerry Tindal

doi:10.51501/jotnafe.v42i1.970

Authors

Jerry Tindal Safe Labs and Engineering Corp https://orcid.org/0000-0002-2568-6649

DOI:

https://doi.org/10.51501/jotnafe.v42i1.970

Keywords:

Modular fireplace, hearth extension, wood burning, chimney, low temperature ignition, smoldering, clearances, fire investigation, methodology, reconstruction, testing, chase, heat transfer, NFPA 921, NFPA 211, UL 127, International Residential Code, IRC, combustible concealed space, conduction, convection, radiant, forensic engineering

Abstract

A fire originated beneath a modular fireplace hearth in a newly constructed home, which then spread into the adjacent chase and attic spaces, resulting in the destruction of the residence. The fireplace was installed on a CMU block riser positioned on a wooden subfloor in violation of the manufacturer’s installation instructions. Scene investigators concluded based on fire patterns and witness observations that the fire originated beneath the fireplace hearth and that the first fuel ignited was wood construction in proximity to the hearth. The author was contacted 3.5 years after the fire during ongoing litigation to review and analyze the available information and determine the cause of the fire. This paper examines the cause of the fire based on forensic engineering analysis and testing. Incorporation of analysis of previous similar cases and testing data as well as new testing data are utilized to reinforce the author’s cause determination.

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