Hanhikivi Training Building

The first building to be completed at Fennovoima’s Hanhikivi nuclear power plant was an architecturally minimalist office building constructed using CLT technology.

Fennovoima Oy is building a nuclear power plant in Hanhikivi in Pyhäjoki. In addition to the actual power plant, there will be dozens of other buildings in the area. The first is a training building that has now been completed.

Among other things, the building will be used to train the employees of the project’s various contractors. As many as 20,000 people will work at the site during the different phases of construction, and 1,600 of them have been trained so far. The building will also house various official services and Fennovoima’s office space.

The building’s design language is minimalist and modern. There is a clear contrast between the open and closed facades. A portion of the glass surfaces on the second floor is covered with wooden slats, which, depending on the viewing angle, make the building appear to open and close when viewed from the outside. The exterior cladding is larch, which fades to grey over time and blends in smoothly with the Hanhikivi landscape. The underlying idea was to make the small-scale, organic material design language grow more generous and metallic as it approaches the power plant.

The first floor consists of a rectangular mass. The main entrance leads directly to a multi-purpose foyer, where customers will be directed to the desired service The space serves as an information point and can also be used for small exhibits. The acoustics of the space are well-suited for concerts. According to the local choir conductor, the space has the best acoustics in the area. The ground floor also houses official offices.

The spaces on the second floor are in two projecting masses. The second floor has two training areas that are used for the orientation of new employees. Fennovoima’s own offices are on the second floor.

A matte epoxy treatment that withstands heavy use was selected as the floor material, and the wall surfaces and doors are oiled CLT and birch veneer with white varnish. The spaces do not have drop ceilings. Instead, HVAC equipment has been left in plain sight against the white varnished birch ceiling. Acoustic mineral wool boards were used for drop ceilings in some of the offices.

The load-bearing and stiffening structure in the exterior walls is CLT board, which has been left visible inside the building. The insulation has been fastened directly to the surface of the CLT board, as has the frame of the exterior larch cladding.

The load-bearing structures in the roof and floor are glued laminated timber beams. The aim was to utilise element construction in every detail of the project, as the implementation schedule was extremely challenging.