Available online at 2019.creative-construction-conference.com/proceedings/ CCC 2019 Proceedings of the Creative Construction Conference (2019) 067 Edited by: Miroslaw J. Skibniewski & Miklos Hajdu https://doi.org/10.3311/CCC2019-067 *Corresponding author: ziga.turk@fgg.uni-lj.si Creative Construction Conference 2019, CCC 2019, 29 June - 2 July 2019, Budapest, Hungary Towards a Parsimonious Information Management for Energy Retrofitting of Buildings Žiga Turk a* , Robert Klinc b , Zhilliang Ma c a,b University of Ljubljana, Jamova 2, 1000 Ljubljana, Slovenia c Tsinghua University, Beijing, China Abstract Throughout the world there are thousands of residential and public buildings that have been built during the reconstruction and rapid urbanization after the 2 nd world war, particularly Eastern and Central Europe as well as in China. These are the most efficient target for mass improvement of their energy use through the improvements of façade insulation and windows. Advanced information technology (IT) - including building information modelling technology (BIM) - is not used very often in these renovations. Our hypothesis is that the use of BIM could be more efficient if it would focus on the essential information needs of the actors involved. The key idea of BIM - structured collaborative shared database of all required information - should be preserved but the model should be parsimonious. The paper presents the ongoing research in the context of a bilateral Chinese-Slovenian project with the goal of designing parsimonious information management for the retrofitting of existing buildings. The broader goal of the work is to study information modelling supporting works where a complete information model may not be needed at all and where a detail process definition - as outlined in BIM execution plan and related documents - would lead to overspecification, constraining the workflow. © 2019 The Authors. Published by Budapest University of Technology and Economics & Diamond Congress Ltd. Peer-review under responsibility of the scientific committee of the Creative Construction Conference 2019. Keywords: building information modeling; energy efficiency; renovation; building process; parsimonious; 1. Introduction Buildings are a major (up to 40%) user of primary energy everywhere in the world. Unlike with cars or electrical appliances - where the next generation can be more energy efficient than the previous one - buildings have a life span of decades or even centuries. The only way to improve the energy efficiency of the buildings is renovation. This is a goal in national strategies of both China and Slovenia (Smart Specialization). It is expected to make a major contribution in tacking climate change. 1.1. Renovation of buildings In Europe, China and in many other countries in the world, there has been a serious housing crisis following the baby boom years after the Second World War. The crisis was being solved by a rapid construction of high-rise apartment towers and blocks. They were being built rapidly and economically, with several copies of each design, and in a time when energy was cheap. Such buildings can be seen at the outskirts of all major European and Chinese towns. The