Refurbishment concepts for a student housing at the Otto Wagner Areal in Vienna under the aspects of sustainability, energy efficiency and heritage protection

For the Otto Wagner area which is situated in the west of Vienna, one pavilion is selected to be refurbished for sustainable and energy-efficient construction to simulate the thermal and energy performance of the building. The selected pavilion has been redesigned to be used as a student residence while preserving the cultural heritage. A dynamic building simulation model is used to improve the energy efficiency and livelihood of Otto Wagner area with the main focus on heritage conservation. The pavilion of four levels is re-designed according to the proposed regulations of plus energy university building to become a student residence. The energy demand can be decreased while preserving the buildings’ heritage requirements. Various changes are made through Sefaira tool in SketchUp model: optimization of the U-values of roof, walls and floor, addition of different layers of sustainable energy efficient insulation materials to decrease the overall energy demand, vacuum insulated panels and rigid cellulose board used to maintain existing roofline and calcium silicate boards to allow for vapor permeability in the brick walls, all working towards achieving the standards of zero energy buildings in Austria. The specific energy demands for heating, cooling and lighting are decreased in the proposed model to reduce the overall energy demand. The main goal of this study is achieving a plus energy district for the entire Otto Wagner area by improving the building envelope and integrating renewable energies using Polysun simulation tool. The selected building achieved the standards of zero energy buildings in Austria by optimizing the energy performance and to assess the thermal comfort in the building, both natural ventilation and mechanical ventilation are used to reduce the summer loads.