Efficient Development of Refurbishment Concepts: Case Studies in Germany

The development of refurbishment concepts for residential buildings is a complex and time-consuming track that requires deep technical knowledge and broad experience. Heterogeneous building typologies with different characteristics and needs for action make the concept developing process more complicated. This paper provides an efficient development approach for refurbishment concepts based on a guideline of prioritised refurbishment recommendations for multi-family houses from the 1970s in Western Germany. These buildings contribute about 2.4 million dwellings (13 %) to the entire multi-family housing stock in Western Germany. In many cases, these multi-family houses are in substantial need of refurbishment measures. In two empirical case studies, the guideline of prioritised refurbishment recommendations is applied and investigated. The refurbishment recommendations are derived from a broad analysis of data from housing corporations and 13,700 energy certificates, a secondary analysis of a representative survey of the housing demand in Germany as well as from 20 expert interviews and an extensive literature review. The case studies indicate that the refurbishment recommendations are suitable for the feasible development of refurbishment concepts for individual multifamily houses from the 1970s in Western Germany. Therefore, the guideline is useful for property owners, real estate developers, engineers, consultants or foreign investors to develop refurbishment alternatives for their buildings and to estimate their costs and economic efficiency.