IEA EBC Annex 55: Reliability of Energy Efficient Building Retrofitting - Probability Assessment of Performance & Cost (RAP-RETRO)

The scope of the project is to develop and provide decision support data and tools for energy retrofitting measures. The tools will be based on probabilistic methodologies for prediction of energy use, life cycle cost and functional performance. The impact of uncertainty on the performance and costs will be considered. Methods based on probability give powerful tools that can provide us with reliable ranges for the outcome.

Short Description

The ultimate outcome of the project will be to develop knowledge and tools that support the use of probability based design strategies in retrofitting of buildings to ensure that the anticipated energy benefits can be realized. These will give reliable information about the true outcome of retrofitting measures regarding energy use, cost and functional performance.

The principle objective will hence be realized by merging hygrothermal building physics with probability and economic analyses. The methods developed will then be applied to optimize energy retrofitting methods.


Austria, Belgium, Brasilia, Canada, Czech Republic, Denmark, Estonia, Finland, France, Germany, Japan, Netherlands, Norway, Portugal, Slovakia, Spain, Sweden, Switzerland, UK, USA

Contact Address

Ao.Univ.Prof. Dipl.-Ing. Dr.techn. Thomas Bednar
Associate Prof. Dipl.-Ing. Dr.techn. Azra Korjenic
Institut für Hochbau und Technologie
Forschungsbereich für Bauphysik und Schallschutz
Technische Universität Wien
Karlsplatz 13/206-2
A-1040 WIEN
Tel.: +43 (1) 58801 - 20602