When the 17 wood floors of the 18-storey student residence at the University of British Columbia (UBC) start being constructed in May, the construction industry will watch to see how prefabricated wood components will speed up the build.
The $51.5-million Brock Commons residence building will stand 53 metres tall (174 feet), house 404 students in 272 studios and 33 four-bedroom units plus have study and social gathering spaces with ground floor common areas for commuter students. It will also become the world's tallest wood building.
Construction began November 2015 on the concrete portion of the structure, the ground floor and two cores.
The project is expected to be completed in summer 2017.
Structurlam is providing five-ply cross laminated timber (CLT) panels measuring 2.8-by-four metres (for floors) and glulam columns, both pre-fitted with quick installation connections, while Centura Building Systems (2013) Ltd. is providing large prefabricated exterior panels, with cladding that is 70 per cent wood fibre.
Bill Downing, president of Structurlam Products, said: "A crane will pull them right off the delivery truck and place them in the building."
Structurlam, the Penticton producer of engineered wood products, is providing "the right panel at the right time" in the hope that construction is expedited and becomes an example for the industry, he said.
The CLT panels will attach to horizontal glulam columns, which are distributed throughout the building's exterior and interior.
The glulams on each floor are aligned. The prefabricated brackets are expected to speed the building's assembly.
Once all components are seated, the metal fasteners are shaped like the Roman number two (II), with the columns seated on the top and bottom and the CLT attached to the sides.
Downing said he is optimistic that two floors per week can be achieved in the construction schedule, which has Seagate Structures installing the panels and columns.
Rob Brown, project management representative for UBC Properties Trust, is more cautious.
"We are saying we will average one floor a week," he said, adding that "it is a new process and while we are aiming to do better, the schedule calls for one floor per week."
There are inevitable production glitches such as winds which can halt the crane.
"So, one week we may do one floor and the next week maybe two. If we get the extra production then, that's great."
Managing director of UBC Infrastructure Development John Metras said that building efficiencies were factored into the construction schedule using prefabricated components.
Wood prefab components are expected to cut the construction schedule by two months compared to a conventional concrete structure. That time-saving is calculation based on an estimate by the design and construction team, he said.
"We are confident that we can erect the wood structure one floor a week. Obviously, if we can move faster that is great, but there are always factors such as the crane, wind and a range of potential risks."
Metras said the main focal point of the building is not a race for the tallest structure but a chance to learn from new technology.
"This is the first one of its kind and it is an opportunity to learn from the experience."
The project's architect, Vancouver's Acton Ostry Architects, is working in collaboration with tall wood advisor Architekten Hermann Kaufmann from Austria.
While the building's structure is heavily reliant upon prefabricated components, the interior is not.
Architect Russell Acton said the prefab industry is still in a neophyte stage in B.C.
"The strategy by the design team was to determine which components could we affect and economically prefabricate," said Acton.
The answer became the structural elements with the objective to enclose the building so that trades could work in a sheltered environment.
"We have amazing trades here and they are used to doing highrise construction. Our strategy then became to use the trades the way they are used to working on the rest of the building," he said.
The building's facade, with prefabricated panels, is a focal point.
"It was designed specifically for this project," said Acton. The panels are eight metres-by-three-metres and made up of eight metre long steel stud-framed sections with pre-installed windows, wood fibre cladding, rain screen and insulation.
"They are craned into place," he said.
The structural engineering firm on the project is Fast & Epp with Robert Jackson and Paul Bernhard Gafner serving as project engineers. Jackson said that efficiencies in construction are being gained several ways through the prefabrication.
"We are separating the concrete and timber trades out," he said, so that while the concrete work is underway, the wood components are being fabricated in the plant.
"That means we also only need one crane on site," he said.
Once concrete work is complete, the building is more of an assembly project than construction.
"It's like a big Meccano set," he said.
Jackson said the crews installing the exterior prefabricated panels would work two storeys below the crews placing the CLT and glulam columns.
In 2015, the B.C. government passed the Building Act promoting innovation in building construction.
The act enabled B.C. to develop a regulation to allow construction of UBC's new tall wood student residence, with rigorous health and safety standards.
The building is also the first to meet the new 2015 rigorous seismic standards under the National Building Code.