A Prefectural Office Building Symbolizing “Gifu, the Land of Clear Streams”

Located in Gifu City, Gifu Prefecture, midway between Tokyo and Kyoto, this project involves the rebuilding of the former prefectural government office, which had become outdated and spatially constrained. Conceived as a symbol of “Gifu, the Land of Clear Streams,” a region characterized by its diverse climates, landscapes, and historical cultures, the building makes extensive use of locally produced materials, including cypress and cedar, Mino washi paper, and ceramic tiles. By bringing together the technologies and craftsmanship of local companies, the project aims to function as a “showcase of Gifu.” The Administrative Building adopts a seismic isolation system located at the top of first-floor columns, allowing the isolation devices and other critical equipment to be positioned above potential flood levels. By eliminating the need for above-ground isolation clearance, the design seamlessly connects the low-rise building with the plaza in front, creating an open space accessible to the community. On the top floor, a highly transparent CLT curtain wall encloses the observation lobby, offering a full panoramic view of Gifu’s landscape and establishing a new regional landmark.

A “showcase for Gifu” created through the integration of local expertise

Located in Gifu City, Gifu Prefecture, midway between Tokyo and Kyoto, this project involves the rebuilding of the former prefectural government office, which had become outdated and spatially constrained. The surrounding area accommodates a concentration of prefectural administrative facilities, including the government office itself.

Gifu has long been known as the land of “Hizan Nosui”—the mountains of Hida and the waters of Mino. In the northern Hida region, 3,000-meter peaks stretch out, while in the southern Mino region, the Nobi Plain is traversed by the Kiso Three Rivers: the Kiso, Nagara, and Ibi rivers. As a symbol of “Gifu, the Land of Clear Streams,” with its broad and diverse climate, natural environment, and historical culture, the project seeks to realize a “showcase for Gifu” through the extensive use of locally produced materials and products, bringing together the technologies of local industries.

A façade reflecting the characters of the prefecture

The project consists of the Administrative Building, composed of low-rise and high-rise building blocks, and the detached Assembly Annex. The exterior employs a variety of custom-made tiles produced within the prefecture, tailored to the scale of each building. From the perspective of long-term maintenance, all exterior finishes are applied using dry construction methods. On the north and south façades of the high-rise block, which serves as the “face” of the government office, prestressed concrete cast with bush-hammered cedar formwork is used to create a deeply articulated external frame. Evoking the traditional chidori lattice patterns of Takayama, the design offers space for maintenance activities such as window cleaning and sealant replacement, while also providing shades to the interior. In this way, a symbolic façade that integrates maintenance performance and environmental control is realized.

A civic building open to the community and conveying the appeal of “the Land of Clear Streams”

Spanning approximately 160-meters east to west across both the Administrative Building and the Assembly Annex, the entrance lobby is open to the community. Finished with locally sourced hinoki (Japanese cypress) timber, Mino washi paper, and ceramic tiles, the space welcomes visitors. Inspired by the “sparkle of water,” its interior features walls cladded in blue-glazed border tiles, a “water-surface” ceiling with floating white boxes resembling the “ripples of water”, and layered bands of timber louvers evoking delicate threads of flowing water. These abstract expressions of water are distributed throughout the space, aiming to recall the fresh and gentle movement of Gifu’s clear streams.

On the north side of the first floor of the Administrative Building, a continuous opening measuring 14.4 meters in width can be fully opened, allowing the interior to be used as a single integrated space with the covered north plaza during events. The “Minamo Hall,” which could be used for symposiums and award ceremonies, is designed to accommodate flexible configurations, including stepped seating with movable stands as well as flat-floor arrangements.

On the 20th floor, the observation floor named “Seiryu Lobby” spans approximately 100 meters east to west and 30 meters north to south, offering an experiential view of Gifu’s defining landscape of mountains and water. A four-side supported curtain wall system accommodates timber-steel hybrid mullions using locally produced sugi (Japanese cedar) CLT. It is positioned above the 3-meter-tall two-sided supported glass facade, creating a highly transparent space with no visual obstructions at eye level. The interior design incorporating Mino washi paper continues seamlessly in the observation elevator halls on each floor and up to the Seiryu Lobby, consistently embodying the building as a showcase for “Gifu, the Land of Clear Streams.”

Achieving high level of resilience and security

From the perspective of improving disaster resilience, the Administrative Building adopts a seismic isolation system at the top of first-floor columns, while critical equipment is concentrated above the anticipated inundation level as a flood mitigation measure.

In emergency situations, movable partitions on the fifth floor can be retracted, allowing the entire floor to function as a single, open center for crisis management. In addition, natural ventilation system utilizing the column spaces around the north and south façades’ perimeter, photovoltaic panels, rainwater utilization, and Cool Heat Trench—an earth tube system that pre-cools and pre-heats outdoor air for air conditioning by harnessing underground temperatures—are incorporated to ensure operational continuity during emergencies while reducing energy consumption during normal conditions.

Furthermore, security gates are installed on the first floor, clearly separating the office areas on the upper floors from the public zones on the lower floors. On the typical floors of the high-rise office section, an open-plan layout is organized around an open central staircase, enabling free movement for staff and enhancing collaboration between departments. By clearly delineating the two zones, the building achieves rigorous information management for prefectural administration and high functional performance in emergency situations. At the same time, spaces outside the security gates are fully opened to the visitors, pursuing an architectural approach that positions the building as a hub for communicating the appeal of the region.

An open assembly chamber while preserving the independence of the assembly

The assembly chamber, located in a separate building (the Assembly Annex), symbolizes the independence of the prefectural assembly. Its curtain wall façade with CLT mullions, designed in continuity with the observation floor, expresses the transparency of the legislative process. The interior is composed using regional materials, including tiles evoking clear streams and groves of trees, a lobby with timber ceiling, wooden furniture, tiles, and ceiling lighting inspired by Mino washi paper. Historical elements such as stained glass and ceramic panels preserved from the former government office are also incorporated as interior features, creating a setting appropriate for deliberating both the past and the future of Gifu.

Project name: Gifu Prefectural Office
Purpose: Government office
Location: Gifu City, Gifu Prefecture
Site area (m2): 33,974.26
Total floor area (m2): 85,384.29
Number of floors: 21 floors above ground, 2 penthouse levels
Eave height / maximum height (m): 105.39／106.19
Main structure: Steel structure, partially steel-reinforced concrete
(Administrative Building: seismic isolation system at the top of first floor columns)

Completion month/year: September 2022

Credits

Client name: Gifu Prefecture
Architect: Nikken・Daiken・Misaki Joint Venture

Main scope:

Nikken・Daiken・Misaki Joint Venture (Concept Design, Schematic Design, Design Development)

Nikken・Daiken Joint Venture (Construction Supervision)

Construction Contractor:

Administrative Building:
Maeda・Dainippon Doboku・TSUCHIYA・Giken Special Construction Joint Venture

Assembly Annex:
Dainippon Doboku・TSUCHIYA・Giken・Seikyo Special Construction Joint Venture

Photo credit 1: ©ToLoLo studio
Photo credit 2: SS Co., Ltd.