Dynamic frame of large timber roof dictates exterior form and internal layout
Uenoa, a Tokyo-based architectural practice, has completed a new building for Synegic, a structural screws manufacturer in the Miyagi prefecture, north of Tokyo.
According to Uenoa, the client wanted to showcase newer possibilities of wooden construction, particularly in light of the fact that it provides the structural screws used to build wooden buildings.
As such, the studio proposed a plan that incorporates a three- dimensional, cross-laminated timber (CLT) roof with a large truss spanning 18 meters.
The three-dimensional roof shape is formed by connecting flat trusses made of laminated timber with triangular CLT panels.
By adopting a CLT panel for fastening flat trusses, complicated processing of joints and joining by hardware are avoided. In addition, it enables a rational method of factory pre-cutting and on-site screw joining.
In addition, the use of heavy CLT panels here, which are traditionally used for walls and floors, represents a new way of incorporating CLT in a roof.
The CLT structure is also used as a partition wall that bears a vertical load on the first floor.
Not only did Uenoa thoroughly try to control the texture of the CLT surface just like marble, they also wanted to use screws factoring in design and workability rather than hardware commonly used to fix CLT walls.
Through such an ambitious process, a large CLT wall that emphasizes the wood texture without modules has been realized in the atrium.
The designers hope that their use of CLT for this building will encourage further experimentation in its application moving forward.
The CLT panels for this project were commissioned to be manufactured by factories in the prefecture, who co-operated in the selection of sapwood lamina from the design stage for the decorative panels used on the walls.
The finished CLT panel was further checked for the texture of the adjacent panels so that the colors of the adjacent panels would match.
The joint of the flat truss was a simple joint mainly consisting of tenon + screw shear joint.
Triangular CLT panels are used for members that connect flat trusses with different inclination angles so that stress transmission at the contact points can be performed rationally, avoiding complicated three-dimensional machining.
Once the ground plane truss was built on the temporary base under the central ridge, the CLT panel was inserted in a wedge shape and integrated.
Along with the construction of the new company building, a workshop called ‘Seed Picking Project’ was conducted in which the seeds of local native species were collected from the surrounding mountains and regenerated on the site of the new company building.
In this area where development is progressing, Uenoa worked to restore the lost local identity and to connect that awareness to the future.
Seeds collected with the co- operation of employees and local people sprouted in the parking lot of the old office building during construction work, and all were transplanted to the new office building site in the spring after the building was completed.
Over the long term, the hope is that a native forest will be created here, and that the intention of this attempt will be inherited not only by the company but also by the community.
Uenoa has developed the building to accommodate Synegic‘s various working styles – from standard desk work to experiments, and collaboration with external researchers – in a way that they can influence each other, creating a lively dialogue and a sense of solidarity.
The office floor plan follows the dynamic frame of the large timber roof, which dictates also the exterior form of the building.
Spread across two levels and a mezzanine platform, the working area balances between the steepness of the space, reinforced by the large roof, and an intimate, warm atmosphere created by the use of wood.