Enclosure fire dynamics with a cross‐laminated timber ceiling

Summary An experimental study of the influence of an exposed combustible ceiling on compartment fire dynamics has been performed. The fire dynamics in compartments with combustible cross‐laminated timber ceilings vs non‐combustible reinforced concrete ceilings in otherwise identical compartments with three different ventilation factors were investigated. The experimental results are compared against predictions from two theoretical models for compartment fire dynamics: (a) the parametric fire model given in EN 1991‐1‐2, and (b) a model developed at Technische Universität Braunschweig, which are the parametric fire models currently used in Germany. It is confirmed that the introduction of a combustible timber ceiling leads to higher temperatures within the enclosure, both under fuel‐controlled and ventilation‐controlled scenarios. It is also demonstrated that the theoretical models considered in this article require refinement in order to adequately represent all relevant scenarios when combustible ceilings are present. A refinement of the German model, by adding the fuel from the combustible ceiling to the occupancy fuel load, was shown to not adequately capture the response for the ventilation‐controlled fires.