Kielotie 13 mixed-use building “Koralli”

Kielotie 13 mixed-use building “Koralli”

Vantaa, Finland

Winner, public procurement negotiated procedure, 2021 / In progress

Client: City of Vantaa

Design-build team: Lehto Group, PES-Architects, Sweco Finland

Project Area: 23,000 m2 (of which 6,000 m² residential)

Functions: Civic, Office, Commercial, Residential

The unique hybrid building at Kielotie 13 in Tikkurila will form a vibrant new heart for the city of Vantaa, part of the Helsinki metropolitan area. Built on the principles of openness and inclusion, the building blends public functions with commercial services and living to create an urban, communal centre that encourages encounters between people in shared, multifunctional spaces.

The name for the design, “Koralli” (coral) refers to the varied and flexible forms and functions of the building. Like a coral reef, the building forms an ecosystem of its own, supporting a rich variety of users and uses throughout the day.

The 23,000 sqm complex contains a mixed-use office building with restaurants and retail premises on the ground floor and three floors of offices for the City’s use, topped by three four-storey residential components. Parking is arranged underground.

The large building mass is broken down into smaller blocks stacked on top of each other like a partly open chest of drawers, forming green terraces and natural shading overhangs. The different functions are located in distinctive blocks, unified by the facade design. The vertical lines of the facade, composed of alternating ceramic and glass elements, create the feel of a classic administrative building in a visual nod to the adjacent City Hall, dating from 1958, while the varying width of the panels gives the building a dynamic, contemporary appearance.

The building steps down towards the City Hall, creating a green, human-scale square in a continuation of the existing urban squares of Tikkurila. The central pedestrian zone continues along indoor streets into the building via entrances on all sides, passing shops and restaurants to converge on the central atrium, or “market square”. The atrium spans the full height of the building and features natural materials and elements, including a wood-clad staircase that rises like a tree to the office floors. Natural light streams in through the skylights.

The City offices are clustered around the atrium and have access to green rooftop terraces and balconies. Citizens’ services and other semi-public areas, such as meeting rooms, are located around the open and easily accessible second-floor lobby, with a direct connection to the adjacent City Hall provided via a glazed bridge.

City employees will be engaged in designing the activity-based work environment using participatory service design methods, taking into account the changing nature of workplaces and the need to accommodate future hybrid forms of working.

In the residential section, apartments come in different shapes and sizes and can be combined to meet individual residents’ needs. A sheltered green roof terrace forms a shared courtyard.

The design allows for easy modifiability of the office and commercial premises over the building’s lifespan, and minimal fixed structures enable reuse of the building if needed.

The carbon footprint of the complex is planned to be up to 55% lower than in an average new build, aiming at LEED Platinum Certification. This will be achieved through careful choice of materials and high energy efficiency, with a CHC heat pump system and roof panels supplying solar power.