The search for ways to build greener, more sustainable buildings has sparked a brand new skyscraper race, but these contestants aren’t made of concrete and steel.
Coming first in the global green race is the Brock Commons, Phase 1, in Vancouver, Canada, which is one of the tallest mass timber buildings in the world and currently under construction at the University of British Columbia’s Point Grey campus. The 18-storey student residence building will provide housing for 400 students and comprise between 300 studio apartments and 30 four-bedroom units plus social and study amenity spaces.
Other candidates include recently proposed structures including a 100-story tower in London, nicknamed the Splinter, and a 40-storey building in Stockholm – but Canada’s is the only under construction.
Canada’s Brock Commons structure is a hybrid system comprised of cross-laminated timber (CLT) floor slabs, glulam columns, steel connectors and concrete cores. When completed in 2017 Brock Commons will stand 53 metres tall.
The building will connect to the UBC District Energy System and has been designed to target LEED Gold certification.
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.
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. After all, building with wood is cheaper, more renewable and much easier to build.
What is CLT (cross-laminated timber)?
Wood is still slightly more expensive than concrete and steel, but according to the University of British Columbia, there’s another benefit. On top of creating fewer greenhouse gas emissions, timber buildings also store carbon dioxide.
New wood engineering technology and ultra-strong bonding means it’s possible to create sheets of plywood-like panels that can provide the equivalent strength of steel.
But what about fire?
The risk of fire has been a problem for those trying to build taller with wood. But since most Canadians live in wooden homes, Canada is the country driving the push and leading innovation to make wooden buildings a big player in the skyscraper game.
According to experts, enormous, chunkier pieces of wood are largely resistant to fires and safe in earthquakes. This means they burn very slowly, then char, then in turn can ‘insulate’ themselves.
The majority of Canadian building codes still limit wood structures to four or six storeys, but increasingly planners are looking at the wood innovations and granting exceptions.