Construction is underway in Vancouver for the world’s tallest timber tower by Acton Ostry Architects. The 18-story Brock Commons Student Residence at the University of British Columbia, which began construction in November 2015, will be completed in the summer of 2017. At 53 meters tall, with housing for 404 students, it will be the tallest mass wood hybrid building in the world. The structure’s two freestanding concrete cores will be completed by the end of May, after which, the erection of the mass wood structure will take place.
The $51.5 million project is being completed with Architekten Hermann Kaufmann of Austria as tall wood advisors, Fast + Epp as structural engineers, GHL Consultants Ltd. as science and building code consultants, and Structurlam as the provider of the mass timber package. Brock Commons demonstrates the benefit of a hybrid design that combines mass wood and concrete, with costs that are comparable to all concrete and steel structures.
The building’s construction is comprised of a one story concrete podium, the two concrete cores currently under construction, and 17 stories of mass timber topped with a prefabricated steel beam and metal deck roof. Lateral stability is provided by the cores, while vertical loads are carried by the timber structure. The building’s glulam columns are fitted with steel connectors that provide a direct load transfer between the columns and a grid of cross laminated timber (CLT) panels, allowing the building to meet new seismic design requirements for the 2015 National Building Code of Canada.
Upon completion of the concrete cores, it is projected that the mass wood hybrid structure and facade will be erected at a rate of at least one floor per week. Speed is being achieved by use of prefabricated materials, including the CLT slab panels, glulam columns, steel connectors, and facade elements. As a proof of concept for the swiftness of construction, a two story project mockup was successfully built in July of last year. The building, which has been designed to target LEED Gold certification, will tap into the UBC district energy system, and by employing carbon-trapping wood construction, it will have a carbon benefit of 2,563 tonnes (the equivalent of taking 490 cars off the road for a year). The hope is that once Brock Commons is completed and able to be studied, British Columbia’s building codes for tall wood structures will be revised and mass wood construction will become more common.