Uses of Wood in the C.K. Choi Building

Seventy per cent of the structural framing in C.K. Choi is made from wood roof trusses salvaged from the 1940’s Armoury Building that was demolished in the early 1990s. The exposed heavy timber framing is distinctive and immediately apparent. Each timber piece was inventoried by size, length, species, and an initial visual grading as the Armoury Building was deconstructed.

For the columns, pieces were spliced together with steel connections to achieve the required three-storey height. To achieve the necessary strength requirements, timber pieces were bolted together to form thicker cross-sections. Metal fasteners were recessed and covered with wooden plugs, as an alternative solution to achieving the required fire rating. Used strategically throughout the project,

Initially, the ungraded wooden beams from the old building presented a problem. At the time, the grader found many checks and cracks in the wood which caused him to doubt of the structural integrity of these members. Yet, by the end of the project, the milestone of making 70% of the structural framing in the building from re-used and salvaged wood members from the demolished building was accomplished.

To achieve the necessary strength requirements, beam timber pieces were bolted together to form thicker cross-sections. Metal fasteners were recessed and covered with wooden plugs, as an alternative solution to achieve the required fire rating.

Additionally new Glulam beams and columns were strategically used to supplement the heavy timber framing members; most notably as the structural support to the custom-shaped curved atrium roofs.

The use of wood in the C.K. Choi building as principal structural members has not only demonstrated the adequate performance of timber elements as main gravity and lateral framing members; it has also served as a benchmark for modern sustainable building requirements which promote the use of recycled and salvaged materials.