Main content:
New passive-house offices for the foundation "Stiftung Waisenhaus" in Frankfurt, Germany
Project participants:
Client: Stiftung Waisenhaus
Architect: Braun & Volleth Architekten
Energy planner: Ingenieurbüro Klöffel GmbH / Engelbach + Partner Ingenieurges. mbH
Gebäudedaten:
Building type: Administration building
Location: Bleichstraße 10, 60313 Frankfurt am Main
Gross floor area: 7.092 m²
Jury evaluation
"The way in which an empty site was developed in Frankfurt’s city centre is a prime example of how a building with pioneering energy standards can blend in naturally in an urban setting. This project with 6,000 m² of NFA can boast excellent solutions to a number of challenges: the conservation of the remains of a city wall, the layout of the floor plan on the confined site that was available, and the tailored development of a high-quality energy solution. The CO2-neutral provision of heating for this passive house using wood is combined with a solar thermal system for cooling using an absorption heat pump during summer operation. To run the building element temperature control in an ideal manner, weather forecasts will also be taken into account."
Project_characterisation
Building concept
This new building has seven storeys above ground plus two further basement storeys. The basement storeys house an underground car park with 38 parking spaces and the technical and storage rooms. The generous entrance area and a lobby for the lecture theatre are located on the ground floor. The staff canteen and the staff kitchen are also on this level.
As the building is being constructed to passive-house standards, controlled ventilation with limited air-change rates is planned. Concrete core temperature control is included in the ceilings to provide heating and, in the summer, cooling. The outer shell and the roof are insulated to the specifications of the passive-house standard. The building will also have an air-tight building envelope, as per passive-house requirements.
Energy concept
The energy requirements for heating and cooling for the building are decreased considerably by the high standards applied to the thermal properties of the building envelope and the reduction in internal loads. An air intake and exhaust system provides the necessary fresh-air turnover in the building. Apart from the highly efficient heat recovery which works at over 85%, no additional temperature control of the air is carried out.
To minimise the thermal bridges present, all linear components end in supports at the interface to the underground car park and the facade supports are also optimised. The use of new types of insulation material, such as Resol, an innovative high-performance insulation material with a thermal conductivity coefficient of 0.022 W/mK, or of vacuum insulation panels in order to optimise the use of space at urban sites is being considered.
Alongside the significant reductions in the energy requirements for the building already achieved, the remaining energy needed for heating and cooling will be supplied from renewable energy sources such as wood pellets and, to a certain degree, solar thermal energy. In this way, the primary energy use can be kept low and the emissions of climate-damaging CO2 can be reduced permanently.