Persevering with our Timber Revolution collection, we take a look at the Tamedia Workplace Constructing by Shigeru Ban – Switzerland’s first seven-storey mass-timber construction that was barely authorized on the time of its completion in 2013.
Designed as an extension to the neighbouring headquarters of Swiss publishing group Tamedia, the workplace takes over a outstanding web site on the banks of the river Sihl and leaves its timber skeleton uncovered for all to see, sheathed solely by the constructing’s glass pores and skin.
Its prefabricated body is made of two,000 cubic metres of glued-laminated timber, held collectively fully with out screws or nails utilizing a novel structural system developed by Japanese architect Ban in collaboration with Swiss engineer Hermann Blumer.
“The Tamedia Workplace Constructing serves as a guiding instance of how structural timber may result in a radically completely different tectonic kind than these already established by metal and concrete,” concluded a paper revealed in Architectural Analysis Quarterly.
The seven-story Mansard-roofed construction flew within the face of native hearth codes, which on the time solely allowed wooden buildings of as much as six tales.
However Blumer managed to tug some strings at GVZ, the municipality’s devoted building-insurance firm, to get the progressive challenge accepted with further fire-safety measures.
“I used to be preceded by the status that once I deal with one thing, it’s normally smart and pioneering,” stated Blumer, who had beforehand helped Ban realise the undulating timber roof of France’s Centre Pompidou-Metz.
“So I made the pilgrimage to the Zurich constructing insurance coverage and was obtained like this: if Hermann Blumer desires one thing, we are able to enable it.”
Two years after the completion of the Tamedia constructing, Switzerland went on to amend its hearth codes and permit timber buildings of any variety – together with high-rises and skyscrapers.
This paved the way in which for record-breaking tasks such because the 100-metre-tall Rocket&Tigerli housing block, which Schmidt Hammer Lassen is presently setting up close to Zurich and which is ready to be the world’s tallest residential timber constructing.
“In hindsight, you may say it pushed the boundaries – on the one hand with the Swiss constructing insurance coverage corporations and alternatively in structure and engineering circles,” Blumer advised Dezeen.
“Individuals realised {that a} seven-storey timber workplace within the metropolis is now allowed,” he continued. “And engineers have been incredulous that such a big picket construction might operate with out metal connections.”
The intuition to forgo fastenings got here from Ban himself, who insisted that they might detract from the pure fantastic thing about the uncovered timber construction.
“He stated a wooden development as stunning as this can’t be defaced by metal components,” Blumer advised the timber development journal Mikado. “So we needed to put our backs into it and make it doable.”
The skeleton of the Tamedia constructing was constructed from a equipment of 1,400 components, together with columns, posts and beams that have been first 3D-modelled on a pc after which digitally fabricated utilizing a CNC mill.
This prefabrication course of took round half a yr. However the construction itself was assembled on web site in solely three months, working in eight sections that every needed to be accomplished earlier than the following might be trucked in, attributable to an absence of cupboard space on the tight city web site.
Every part consists of 4 columns – extending as much as the constructing’s full 21-metre top beneath the Mansard roof – and 5 double cross-beams with forked ends that have been designed to fit across the columns.
Strategic holes at their connection factors enable for the insertion of an extended, horizontal spacer beam, which is pushed all through every column in a given row to successfully lock collectively all of the completely different components.
The system was knowledgeable each by conventional Swiss craftsmanship and the frilly joints of Japanese miyadaiku carpentry – used to assemble a number of the world’s longest-surviving picket buildings resembling Horyuji Temple in Nara, which is over a thousand years outdated.
To make sure the steadiness of the joints at such a big scale with out the necessity for metallic fastenings, Blumer milled the spacer beams into an oval moderately than a conventional spherical form to forestall them from rotating.
As well as, the constructing’s structural body is made fully from slow-grown glued-laminated spruce sourced from not less than 1,000 metres above sea degree within the Steiermark area of neighbouring Austria.
“These circumstances give the timber higher properties than timber with a sooner development price, together with improved dimensional stability,” reported Swedish wooden journal Trä.
To additional reinforce the joints, Blumer glued thick plates and dowels made from beech plywood contained in the connection factors, offering improved transverse power attributable to its multi-directional graining.
“The concept of a beech peg may seem to be a brand new innovation, however the system has really been put to make use of earlier than in manufacturing,” the engineer advised Trä. “Wood pegs was employed to repair the bearings in place on rotating metallic axles.”
Organized right into a double row that runs all the way in which across the periphery of the constructing, the columns act as vertical trusses to carry up the flooring.
The timber skeleton is left utterly untreated and uncovered all through the constructing, to create the impression of standing amongst a forest of timber.
As an alternative of including fire-proof cladding across the timber, the structural components have been over-dimensioned by 40 millimetres on all sides.
Based on the engineers, this exterior layer will flip to char when it comes into contact with hearth and defend the core for as much as 60 minutes.
Ban additionally added two concrete staircases to supply emergency exists, in addition to cladding the constructing’s timber partitions and ceilings in gypsum board and cement-bonded particle board to additional enhance its hearth security.
The glass facade basically features as a pores and skin over the body, moderately than being a structural factor in its personal proper.
Past simply triple glazing, Ban put in further energy-efficiency measures together with a three-metre-deep double facade on the river-facing aspect, within the area between its double row of columns.
This successfully acts as a thermal buffer in addition to offering pure air flow, since complete sections of the facade could be opened up on motorised tracks to create impromptu balconies.
Based on Ban, the structural system developed for the Tamedia constructing might simply be used to construct the taller buildings that are actually dominating the mass-timber scene.
“I could make a a lot greater constructing with the identical system,” he advised Azure on the time. “If the location have been completely different, the construction might be greater or smaller, however the joinery could be the identical.”
The pictures is by Didier Boy de la Tour.
Timber Revolution
This text is a part of Dezeen’s Timber Revolution collection, which explores the potential of mass timber and asks whether or not going again to wooden as our major development materials can lead the world to a extra sustainable future.
