zertifiziert durch TÜV Rheinland
  Certipedia-ID 0000021410,


The office was founded in 1990. The founders Heike Fischer and Wilhelm Stahl were previously longstanding members of staff at the Fraunhofer-Institut für Solare Energiesysteme in Freiburg.

Since January 2004, the office has been operated as a GbR by Volker Weiss in partnership with Wilhem Stahl.

We implement cross-industry services for the energy and comfort planning of buildings. Our aims are: Natural comfort, minimal energy consumption and the use of regenerative energies with reduced investment and operating costs, whereby we constantly take architectural issues into consideration.

We offer our services in accordance with HOAI and as special engineering services with fixed rate payments.

The company focuses on:

  • Design of energy concepts
  • Building physical consulting
  • Energy pass according
  • Thermal bridge calculation
  • KfW - consulting
  • Passive house projecting
  • Noise protection proof
  • Room acoustic calculations
  • Dynamic building simulations
  • Illumination simulations
  • Fluid-dynamic simulations
  • Water concepts
  • Construction material consulting
  • Economic calculations
  • Building physics attendance of timber constructions
  • Sustainability certification according to DGNB/BNB/NBBW

Office management: Partnership between Prof. Dr. Wilhelm Stahl and Dipl.-Ing. Volker Weiß

Members of staff: 1 physicists, 9 engineers, 2 architects, 1 drafter, 1 office expert

In addition, our office also provides workplaces for school work experience and internships as well as thesis opportunities

Office equipment: Server, network, 16 computer work stations with all the associated hardware components

Software resources: TRNSYS, HEAT 2D + 3D, FLUENT, RADIANCE, CATT Acoustic, IBP18599, ECAD, Ecitect, T SOL