Together with Nicola Rigoni and Matteo Novati, I worked on the redesigning of the Tietgen Kollegiet dormitory in Copenhagen. The purpose of the project was to first conduct an energy analysis on the current building, and then to apply new energy standards and technology to the building. The project had to present the architectural and engineering design choices. The building was designed with a new structure based on gasometers, in order to promote the renewal of extisting structure. A special attention was given to the materials used, and the use of renewable and recycled materials was maximized. In this project simulations with BSIM, Be06, and HEAT were conducted. The building new geometry assures that the daylight distribution is optimal, and that the passive energy gain from the sun is at its best.