The energy-efficient building of the RAL Institute plays with all colors

The facade of the new headquarters of the RAL Institute in Bonn leaves no doubt as to who is the client and user of this building. A total of 428 large-format glass blades from Schüco ALB powered by solar energy provide shade while protecting almost all offices and meeting rooms from overheating. The building stands out with its original solution of glass blades tinted by screen printing in an almost endless range of RAL color shades, which has been inextricably linked to this German institute for quality assurance and certification for more than 90 years.www.schueco.cz

The representative, barrier-free, and incredibly energy-efficient office and storage spaces of the RAL Institute - Deutsches Institut für Gütesicherung und Kennzeichnung (German Institute for Quality Assurance and Certification) - and its subsidiary RAL gGmbH are located in the Am Mühlenbach business zone in Bonn. On the occasion of its return to its native Bonn, this established institute with a long tradition wished to build a new headquarters that embodies its values. The project was successfully completed in 2017. "Functionality, quality of life, identity at the highest technical and sustainable level thanks to the latest elements and technologies used in everyday operations, with quality products and services certified by the RAL institute." The external appearance of the building was intended to surpass these "internal values" and become a first-class and attractive building that clearly references the core expertise of the RAL institute and represents an imaginative solitaire in itself.

Rounded building among rectangular structures

The western side of the new technology park "Am Mühlenbach," occupied by functional, strictly rectangular buildings, has been enlivened by the Architectural Studio Frank Piotrowski, which designed a gently rounded object. The project was inspired by the adjacent area of the extensive valley floodplain, after which the Mühlenbach business zone is named. The tension between rectangular and rounded forms allowed for unusual room layouts within the defined space in the new building.

The part of the building on Sankt Augustiner Straße, facing the most demanding traffic and the most difficult to furnish due to its northern orientation, has a strictly rectangular shape. It houses the essential underground parking, main storage areas, and modern technologically equipped color laboratories on the ground floor, as well as an office atrium on the first floor. This arrangement allows for easy and unobstructed material loading and unloading. The facade of the storage area has no windows and can thus serve as an advertising space - it features a white backlit logo, making the new headquarters of the RAL institute easily identifiable by its well-known design.

The depth of the building allowed for the first floor to be divided into three office sections centered around the atrium in the central part. The connecting corridors are equipped with lighting that enhances other visual elements. Access to the management offices can be made separately via a staircase.

The strictly rectangular mass of the building oriented towards Sankt Augustiner Straße contrasts with the subtly rounded shape on the western side. The technical background of the building and archives are hidden in the basement. On the ground floor, there are public meeting rooms with a view of the green Mühlenbach plain. The first floor, divided into two parts, is entirely reserved for office use. At the junction of both wings of the building, the designers placed a central entrance with a reception area and access to the single staircase for the entire building.

Solar-powered glass blades in shades of the RAL color scale

The dynamic contrast between the different shapes of the building continues in the facade design. The visually robust ground floor clad in limestone serves as a base for the lighter first floor, fully glazed to its height, and for the flat roof, which notably overhangs the mass of the building on all sides. Above the base, specially designed glass louvered blades dominate, serving to shade the interiors of the building.

The glass blades, covered with a translucent perforated layer in various colors, extend across the entire first floor. They rotate around their central axis and adjust their angle according to the position of the sun using a drive mechanism, providing pleasant illumination in the adjacent rooms thanks to their translucent surface. The carefully graduated color shades from the RAL scale also effectively evoke one of the client's main fields of activity. Additionally, they open up entirely new areas of application, as there is currently no standardization for using RAL colors for the surface treatment of glass panels.

More than 80 different color shades of Schüco ALB blades

Technologically, the outdoor shading solution is based on the system of large-format louvered blades from Schüco ALB. The facade is equipped with movable glass blades in more than 80 different color shades, each measuring 3 or 3.5 meters in height and approximately 50 centimeters in width and weighing 100 or 120 kilograms, respectively. They can be rotated up to 90° and thus automatically adjust to the angle of sunlight. The motors required for their rotation are embedded in hidden aluminum support profiles. Linear drives, each rated at 3000 N, ensure quiet and precise movement of 428 blades depending on the position of the sun.

An additional innovation used by the designers for some of the meeting rooms and offices without shading by vertical louvered blades is the Schüco FW 50+.SI facade with electrochromatic glass from Saint-Gobain. The light transmittance of this dynamically colorable glass can be regulated according to requirements at four levels, ranging from 1% to 60%. Depending on solar radiation, shading and heat gain can also be controlled.

The technologically demanding shading, facade, and window systems with relatively complex design elements were produced by the experienced manufacturer Keskin Fensterbau GmbH, a partner company of Schüco based in Troisdorf.

Energy efficiency and ecology at the highest level

All external surfaces of the RAL Institute headquarters have excellent thermal insulation, which significantly slows down the loss of internal heat while also limiting overheating from external heat despite the extensive glass surfaces. Thanks to natural light and warmth, the need for artificial lighting and heating is reduced. Regulated ventilation through heat exchangers extracts heat from the used air and heats the incoming fresh air. Thanks to these measures, the primary energy consumption of the building remains at 52 kWh/(m².a), easily meeting the strict limit of 55 specified for low-energy buildings as per KfW. The heat consumption is 5 kWh/(m².a), and the energy required to ensure electricity is 30 kWh/(m².a).

Light sensors based on daylight regulate the intensity of artificial lighting

An important role in the extremely low energy consumption is played by the amount of natural light. Well-insulated windows and facade elements from Schüco contribute to reducing the need for artificial lighting. Light sensors installed in each room calculate the current amount of daylight and subsequently regulate the intensity and color of the artificial lighting provided by the installed lamps. Energy for heating and cooling is supplied by a geothermal heat pump, which is part of a closed circuit with 20 deep boreholes. Throughout the year, energy is extracted from the ground in winter and returned in summer. In addition, the boreholes serve as a source of heat for surface heating and as an active source of cooling for surface cooling purposes.

All rooms in the new building are equipped with a controlled clean ventilation system that allows for gradual regulation of the supplied fresh air/external air as needed in individual rooms. Although it is still possible to open windows (Schüco AWS 75.SI+), which, due to excellent insulation, reduce energy consumption and noise levels, it is no longer strictly necessary. Closed windows significantly limit external noise penetrating from the busy Sankt Augustiner Straße.

Transparent fire doors protect against the spread of fire and smoke

Thanks to the design solution of the building, a single staircase is sufficient for the entire structure. Direct escape routes from all rooms are a maximum of 35 meters long. Individual fire compartments (rectangular office section, rectangular management section, rounded construction) do not exceed 400 m² in area, and no further fire safety measures need to be implemented within these compartments. The staircase is separated from the individual fire compartments (basement garages, storage, offices) by large, glazed, automatic fire doors that prevent the spread of fire and smoke. Specifically, the project used double-leaf doors with the ability to regulate the closing sequence of the leaves from the Schüco ADS 80 FR 30, Schüco Firestop T90/F90, and Schüco ADS 65.NI SP systems. The barrier-free solution of the project includes motorized locks, push buttons for door opening, and card code operations at all locked doors. Smoke from storage areas is removed by a separate smoke extractor fan with a capacity of 10,000 m³ per hour.

The atrium has become a home for bees

The philosophy of the RAL Institute, which visitors are introduced to immediately upon entry, is fully in line with the holistic and sustainable concept of the building, perfectly thought out from overall energy efficiency to all ecological details. For example, the new headquarters of the RAL Institute features surface drainage with underground tanks, roof greenery, and a 10 kW photovoltaic system installed on the roof, complemented by three rapid charging stations for electric vehicles. The remaining electricity needed to operate the building is provided by certified green energy from sustainable sources. The design of the outdoor spaces respects nature and limits the built area to a minimum. The atrium on the first floor has also become a new home for a bee colony.

Project information