Robustness of renovation scenarios according to the passive house standard

Abstract

The present master thesis has emerged in the context of the building refurbishment goals of the Swiss Energy Strategy 2050. It is to determine the robustness of renovation scenar- ios based on the passive house standard in comparison with general renovation solutions. The robustness of the heating demand, the life cycle costs (LCC), and the life cycle as- sessment (LCA) is evaluated for representative multi-family dwellings from different time periods. For every case study building, the heating demand, LCC, and LCA are calcu- lated using a Python code. Moreover, the Matlab-based framework called UQLab is used for the uncertainty quantification and therefore to identify the robustness of renovation solutions.

A passive house renovation solution could not be found for every case study building. Old multi-family dwellings built in the inter-war period or before can not be renovated according to the analysed standard. For the newer case studies, built in the post-war or the economic boom period, robust passive house renovation methods could be found. The optimal solution in terms of LCA and LCC is the general renovation of the building’s shell and the installation of a heat pump heating. The installation of a mechanical ventilation system, to reach the passive house standard, requires a big financial investment which can not be compensated by the passive house benefits in terms of LCA and LCC.

To enable a detailed analysis of the scenarios, the LCA and LCC results should be split into their individual causes. For example, the used materials, the window replacements, and the heating emissions and costs. Although the renovation of multi-family buildings to passive house standard does not seem worthwhile, this should not diminish the advantages of a newly built passive house in terms of the high standard of quality and comfort.