Resistance to transformation: synthetic visual indicators to evaluate the environmental impact of building refurbishment through the use of BIM models

Refurbishment design is a complex operation, which has to take into account multiple constraints, and that imposes numerous choices. Every project produces an impact on the environment due to demolition and reconstruction processes. To optimize the use of resources, and to reduce the impact of transformation, synthetic indicators that can support designers and planners in evaluating the impact of the different design alternatives should be considered in the early phase of the design process. Thanks to rapid response data evaluation, the increasing diffusion of BIM technologies allows to quantification of the impact on the environment of alternative measures from the very first phases of building design. The main aim is to give designers a synthetic estimation of the impacts generated by transformation of existing buildings in the early stages of the design process. These indicators should be clearly and rapidly comprehensible. The overall impact is measured through the specific environmental impacts, namely GWP (Global Warming Potential) indicators, for demolition as well as for reconstruction. Values are taken from the existing LCA (Life Cycle Assessment) database. BIM Models allow combination of building elements with synthetic values for the GWP indicators. Every modification of the building model can generate an image of the impact with different colors, similar to thermographies.