The ‘Neues Regionshaus’ building is an addition to a complex of existing buildings in Hanover’s city centre. The compact reinforced-concrete extension forms an additional inner courtyard together with the existing structures. The character of the surrounding buildings is defined by the ‘Stadtbibliothek’ – the City Library, which is housed in a listed Expressionist building – and other buildings dating from the 1950s. The materials and colour scheme blend in with those of the existing surroundings. The well-defined facade was built using bright limestone and dark anthracite-coloured granite, which makes the window openings in the facade appear larger. The ‘Regionssaal’ hall stands out prominently in front of the six-storey new building and extends almost as far as the public footpath. The result is a harmonious combination of the old and the new. The hall building, which can accommodate 540 people and be divided into three smaller halls if necessary, allows for maximum use of daylight, even when the hall is divided into smaller units.

For cost reasons, it was decided not to include basements or an underground car park. Parking spaces were provided at the rear of the site. Wood-aluminium windows with insulating glass units and 16-cm external wall insulation made of mineral wool ensure good thermal insulation of the air-tight facades.

There are 191 office rooms, each intended for two employees, in the upper storeys. The 20-m² rooms are comfortably furnished and equipped for the users. For example, sun and glare protection is integrated into the cavity between the glass panes in the window units, with daylight redirection in the upper third. Daylight can enter even when the sun protection is closed. In the case of strong solar irradiation, the sun protection is automatically pulled down once per day during a time period that depends on the orientation of the facade. The sun protection can also be operated manually, in which case automatic control is switched off for the rest of the day. The lighting, which is controlled based on presence and brightness and has both direct and indirect elements, adds to the energy-efficient lighting concept. The ability to switch off the power supply to all the equipment sockets on each floor and concrete core activation for room cooling both lead to further comfort and energy savings. Because of the concrete core activation, sound-absorbing ceiling panels were installed to improve the room acoustics.

Based on the experience of other regional bodies, the client, the Hanover region, considered whether to implement the project as part of a Public-Private Partnership, or PPP for short. This idea was investigated by means of a feasibility study which had the goal of identifying potential economic benefits. The results of this study were positive, and so the region decided to use the PPP financing model. The various services such as planning, construction, financing and, if necessary, operation can be acquired as a single package, which is in contrast to conventional acquisition methods for public clients. The private company can then operate independently and carries risks itself; when purchasing services, it does not have to act in accordance with the formalities and decision-making processes which apply to public bodies.

The PPP tender defines all the important targets – such as energy efficiency and user comfort in the case of the ‘Regionshaus’ in Hanover. According to the criteria in the tender, the most cost-effective offer will be awarded the contract. The next step is to negotiate the details of the contract between the contractor and, in this case, the Hanover region. The contract is a combination of a construction contract and a financing contract. Once the building has been handed over in a ready-to-occupy state, the quarterly payments commence and continue over a period of 20 years, after which the building becomes the property of the client.