A research project, Wood and Wood-Hybrid Midrise Buildings, was undertaken to develop information to be used as the basis for alternative/acceptable solutions for mid-rise construction using wood structural elements. As part of this project, four large-scale fire experiments were conducted to evaluate the fire performance of two forms of encapsulated combustible structural wood systems, a lightweight wood-frame (LWF) system (2 experiments [3, 4]) and a crosslaminated timber (CLT) system (1 experiment). The fourth experiment [5] involved a test structure constructed using a steel frame system described below. Each experiment involved construction of a test set-up of an unsprinklered full-size apartment unit, intended to represent a portion of a mid-rise (e.g. six-storey) building.
The structural elements used in the LWF system (wood stud walls and wood I-joist floors) and CLT system (3-ply wall panels and 5-ply floor panels) were all chosen on the basis of the types of construction that were currently being used in 5- and 6-storey mid-rise residential construction being built in the province of British Columbia, where the building code had changed earlier, in 2009, to permit such mid-rise combustible construction. This report provides the results of the experiment with an encapsulated CLT setup representing an apartment in a mid-rise (e.g. six-storey) building.