Abstract 

A significant aspect of deep-energy retrofits involves the recording and modelling of existing conditions. This paper discusses proposed best practices and ongoing challenges. Our discussion draws on the work of the Carleton Immersive Media Studio (CIMS) over the past decade in the context of heritage documentation and Heritage Building Information Modelling (HBIM). In contrast to recording and modelling for heritage — which demands a high level of correspondence between the physical asset, the data from the documentation process, and the HBIM — the retrofitting of non-heritage buildings for energy performance has little or no imperative to preserve the character of the original building. Rather, deep energy retrofits typically look to reconcile generalized construction solutions with unique as-built conditions. In comparing techniques for recording architectural heritage with techniques for capturing as-built conditions for deep energy retrofits, questions of levels of detail, information, and accuracy become paramount. Recognizing the differences but drawing on our experience in HBIM, we argue that accurate modelling from point clouds in a BIM environment can allow for a better understanding of the deformations of a building prior to fabrication — allowing designers to better understand how the building has deformed in non-uniform ways. The paper will examine the processes of building capture and modelling in a BIM environment for a deep energy retrofit of a commercial building constructed in the 1970’s. Similarities and differences in scan-to-BIM best practices for heritage and rehabilitation will be discussed.