In an attempt to prevent the spread of fire and smoke beyond the compartment in which the fire starts, regulations often require building construction such as walls and floors to exhibit varying degrees of fire resistance. Since penetrations for building service equipment and systems in wall and floor assemblies acting as fire separations are unavoidable, steps must be taken to ensure these penetrations do not compromise the fire resistance of the compartmentation. As designers embrace taller and larger wood buildings, and as new massive wood products such as cross-laminated timber (CLT) become available, fire stop solutions for massive-wood structures are becoming increasingly necessary.
Currently, there are no listed fire stop systems available for service penetrations in solid wood wall and floor assemblies in North America. The lack of available listed and generic fire stop systems for solid wood construction, especially for massive wood products such as CLT poses a challenge to architects and engineers in their effort to gain acceptance of a proposed design from an Authority Having Jurisdiction (AHJ).
To this end, the wood industry is interested in facilitating the development and approval of fire stop systems for solid wood construction such as CLT construction. The following report provides background information on the standard test method used in Canada to evaluate fire stop systems, ULC S115, “Standard Method of Fire Tests of Firestop Systems” and the regulatory requirements specified in the National Building Code of Canada (NBCC).
A review of research conducted in Europe demonstrates that fire stop systems currently used in reinforced concrete and light-frame construction can be used with success in solid wood construction. While testing conducted in Europe has largely relied on lining the reveal of openings with gypsum board, a limited number of tests indicate that lining methodology using gypsum board may not be necessary in all cases.
The highest priority for facilitating the development and approval of fire stop systems is in wood structures up to 6 storeys tall. This is due to the fact that these buildings are currently permitted in the British Columbia Building Code (BCBC) and are likely to be permitted in other provinces as well as in the 2015 edition of the NBCC.
In order to help the wood industry in moving forward in addressing fire stops issues, three paths are identified and discussed in which the wood industry could facilitate the development of approved fire stop systems for solid wood construction. Ultimately, it is the fire stop manufacturers who must conduct testing in order to seek fire stop listings. Therefore, it is highly recommended that testing be conducted in cooperation with one or more fire stop manufacturers.