Surveying and digital workflow in energy performance retrofit projects using prefabricated elements

Due to the need for improving the energy efficiency of existing buildings, various methods for energy retrofitting are being developed. One such initiative is the TES Energy Façade project, a joint European academia and industry project under the umbrella of the WoodWisdom Net research platform. The project has developed a systematic approach for using prefabricated timber-framed elements that can be assembled in front of an existing façade. The TES approach requires a detailed and precise documentation of the as-built/as-maintained conditions of the existing façade. This paper discusses the approach for the surveying and documentation of a building's existing state and the need to establish a continuous digital chain that encompasses the various project stages from the survey to the site assembly of the elements. Technologies such as 3D laser scanning and BIM are efficient tools in the process but are not yet sufficiently developed to handle all of the challenges in renewal and retrofit projects.