The building complex of the University of Mannheim was erected in 1971/1972 according to a standard “university building system” using prefabricated concrete frames. Later, larger room modules for lecture halls, seminar and PC rooms were integrated, which has led to the following problems:

• insufficient ventilation (ventilation through the windows restricted because of noise exposure)
• sound insulation insufficient
• high heat loads from persons and PC concentration.

THE NEW ROOM STRUCTURE:

• new dimensions and uses thanks to movable wall components in lecture halls and seminar rooms
• additional space available in the basement thanks to the new light well directing glare-free daylight into the rooms.

STEEL AND GLASS SHELL AS A DOUBLE FACADE WITH THE FOLLOWING EFFECTS:

• avoiding a costly renovation of the concrete structure (only “cosmetic“ measures)
• improving the facilities’ properties in terms of building physics (protection against the weather and the cold)
• better noise protection, ventilation with open windows now possible
• ventilation with open windows during the night without safety risks
• energy-intensive air-conditioning of the room not necessary thanks to combination with earth duct
• sustainable solution with reduced maintenance costs and low energy consumption  
• providing more comfort for users of the building.

HOW THE DOUBLE FACADE WORKS:

The double-leaf facade reduces heat loss caused by ventilation and transmission, preheats the supply air by solar energy, provides a comfortable indoor climate near the facade and a controlled natural ventilation in case of high wind speeds and calms; it captures heat from the outgoing air, shields the outer sun protection from weather effects and improves noise protection. During the night, ventilation with open windows helps re-cool the storage masses; at the same time, the double facade protects the building from rain and burglary.

Fresh air sucked in through the ground floor and controllable ventilation slats is directed upwards in the area between the facade leaves through natural convection (“air collector”) and is transferred outside after having passed not more than three storeys.