Risk Assessment for Energy Efficient Refurbishment of 19th Century Townhouses Using Interior Insulation

Abstract

The paper deals with the thermal rehabilitation of 19th century townhouses using interior insulation. It presents the latest research results of two ongoing projects of the Research Centre of Building Physics and Sound Protection of Vienna University of Technology. Essential details concerning the renovation - focusing on the thermal rehabilitation of an exterior wall, e.g. interior insulated wooden beam connections - are discussed. It is shown, how the risk of damage of an inside insulated construction can be assessed by hygrothermal simulations and the analysis of certain issues. A planning example of an internally insulated exterior wall with wooden beam connections is presented. The worst case scenario is described by variation of certain boundary conditions. It is shown how selective tempering of the joist bearing can minimize the risk of damage as well as the energy expenditure. Besides the description of the technology of wooden beams´ temperature controlling, a patent is introduced which is currently being further developed in an ongoing Project of the Research Centre of Building Physics and Sound Protection of Vienna University of Technology.