Unilever, Hamburg

First-rate sustainable architecture in Hamburg’s HafenCity

The new Unilever headquarters in Hamburg/
Solar control glass optimises the energy balance  

HafenCity Hamburg is located right at the bank of the Elbe River. This inner-city construction project, currently the largest in Europe, features modern and sustainable architecture. One example is the Unilever building that was designed by Behnisch Architects: Graceful like an “ocean liner”, the new headquarters of the consumer goods producer is located at Strandkai 1. The building combines climate protection and transparency:ipasol solar control glass (Interpane) allows for high levels of daylight transmission and, therefore, it lowers the costs for indoor lighting. At the same time, it also prevents the rooms from heating up too much on hot summer days and thereby reduces the need for air conditioning. Seven levels spanning 30,000 square metres provide plenty of room for 1,200 employees to interact and communicate.

Right between Speicherstadt and the Elbe River, on an area of 157 hectares, a new quarter with residential buildings, office buildings, shopping centres, restaurants and leisure time facilities is growing – Hamburg’s HafenCity. This growing process will continue well into the 2020s. A total of 40,000 new jobs will be created. 

A new architectural highlight in the skyline is the new Unilever headquarters for Germany, Austria, and Switzerland. The building resembles the cruise ships that are anchored in the immediate vicinity. Inside the building, the enormous transparency generates a feeling of openness and freedom. The peripheral ipasol solar control glazing facade promotes this concept with its high level of daylight transmission, while preventing excessive heat build-up at the same time in the case of intensive solar radiation. There are hardly any small individual offices: Bridges and stairs connect the wings; conferences take place in so-called “meeting points” that exist on each level and have a positive impact on communication among the staff. Its atrium is the heart of the building: As a “communication spot”, it is accessible to the staff and visitors alike – a concept that underscores Unilever’s company philosophy of “openness, vitality, and quality of life.”

Awarded for sustainability

The building sets new ecological standards: The golden environment award of the HafenCity Hamburg GmbH, the WAF (World Architecture Festival Award), and the international Bex award (Building Exchange Award) are all proof of its sustainable and architectural excellence. The façade, which features ipasol solar control glazing, optimises the energy balance: In warm months, it minimises the costs for air conditioning, and in cold months, its insulation value of 1.1 W/m2K (as per EN 673) keeps the warmth inside the building. Another part of the energy concept is the application of LED technology for lighting the workplaces. This reduces power consumption by up to 70 per cent compared to using halogen lamps. Due to the close vicinity of the cruise terminal, special attention had to be paid to the emissions of the ships’ motors. The planners, therefore, implemented a special hybrid ventilation system: The primary ventilation is a mechanical type employing compressed air systems in the floor. Via a filter system, outside air is distributed through the offices and then into the atrium, where the air rises up. Heat exchangers inside the roof minimise the heat losses.

A “Cocoon” protects the glass facade

The small drops that are churned up by the rough maritime climate can soil the facade. In order to protect it, but also for design reasons, it is covered by a single-layer, fully transparent plastic cover. This also supports the association with ships, which is intended for the viewers of the building: Under certain weather conditions, it inflates like a sail and hisses in the wind. It also allows the construction to be without horizontal seals, which would have been necessary for fire protection reasons with the use of a double facade. The space between the facades is ventilated and, therefore, it also supplies draught-free fresh air through open windows.

Daylight and comfortable temperatures – all year long

Neutral views, lots of daylight and a high level of solar protection are the strengths of the ipasol neutral solar control facade. It comprises two parts: On the ground floor, the generously dimensioned glazing in a pillar-beam design allows plenty of light into the building. Especially in the summer months, the reflecting water caused the facade to let in considerably more light and heat. Therefore, the planners decided to use ipasol neutral 50/27: With the large windows and the special light intensity, as little as 50 per cent of daylight transmission provides for bright rooms, so that artificial light only has to be used relatively late in the day. This reduces the operating costs and is good for the environment. The particularly low solar factor (27 per cent as per EN 410) effectively protects the rooms from heating up too much on sunny days. This reduces the costs for air conditioning. The neutral glass also allows for a pristine view from the offices over the Elbe River and HafenCity.

From the first storey upwards, the glass facade is protected from the rough sea air by a “plastic cocoon”. Since the sophisticated cover, despite its high transparency, reduces light transmittance, the planners decided to use ipasol neutral 70/39.
The high level of light transmittance (tL = 70%) maximises the daylight transmission. Together with the “plastic sail” enclosing the building, the solar factor of 39 per cent is sufficiently low. In the wintertime, the Ug-value of 1.1 W/m2K (as per EN 673) provides for effective heat insulation. In some parts of the building, a cold sound-insulation facade, using laminated sheet glass supplied by Interpane, provides additional protection from increased noise levels.

photo: Interpane / Adam Mørk

The building sets new ecological standards and has already won several awards.
ipasol solar control glass optimises the energy balance.
download image (300 dpi) 

photo:  Interpane / Adam Mørk

The new Unilever headquarters in Hamburg’s HafenCity: A sophisticated plastic cover protects the solar control glass facade against the rough maritime climate.
download image (300 dpi)