Residential Structure Separation Fire Experiments

Published

August 1, 2008

Author(s)

Alexander Maranghides, Erik L. Johnsson

Abstract

Building codes often allow structures with window openings and combustible exteriors to be built with as little as 1.8 m (6 ft) of separation between them. In a recent full-scale laboratory experiment at the National Institute of Standards and Technology (NIST), it took less than 80 s for flames from a simulated house with combustible exterior walls to ignite a similar "house" 1.8 m (6 ft) away. In another experiment, involving the same type of structures, the flames from one simulated house again reached the second, but this time a gypsum barrier protected the simulated home from sustained ignition. The experiments showed that an adjacent structure can be ignited if flames from a fire inside a house exit through window openings. The experiments illustrated how a fire resistant barrier can, in the scenario tested, slow down flame spread between two structures separated by 1.8 m (6 ft). The scenarios tested were not the worst case. Flame spread between structures is a complex process primarily affected by structure construction type, structure separation distance, placement and size of windows and weather conditions.

Citation

Technical Note (NIST TN) - 1600

Report Number

1600

NIST Pub Series

Technical Note (NIST TN)

Pub Type

NIST Pubs

Download Paper

https://doi.org/10.6028/NIST.TN.1600

Local Download

Keywords

residential fires, residential structures, structure separation distance, community fire spread, multi-structure fires

Citation

Maranghides, A. and Johnsson, E. (2008), Residential Structure Separation Fire Experiments, Technical Note (NIST TN), National Institute of Standards and Technology, Gaithersburg, MD, [online], https://doi.org/10.6028/NIST.TN.1600, https://tsapps.nist.gov/publication/get_pdf.cfm?pub_id=861598 (Accessed May 6, 2026)

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