LOW-COST 4D BIM MODELLING: A COMPARISON BETWEEN FREECAD AND COMMERCIAL SOFTWARE

Abstract. The paper aims to investigate the potential inherent in a FOSS (Free and Open Source Software) approach for the 4D BIM modelling using Freecad. In order to reach this goal it shows a comparison of Freecad features with those of commercial software, considering the evaluation of the effective application of this Open Source software in the professional environment, and highlighting the progress in the FOSS BIM area, that still represents an unexplored study field if compared to the vast publications related to BIM modelling that occurred in the last two decades. To this end, the study has been carried out on a singular case study, a steel canopy which has been designed for the urban renewal of a public space in Teramo. Despite its size, the canopy required the definition of complex details. Its structural system has addressed the study to compare Freecad with some software dedicated to steel structures or particularly suitable for the modelling of this specific structural typology: Tekla Structures and Sketchup. Starting from a concise historical reconstruction of the FOSS spread, the paper introduces a brief overview of the potential of Freecad in terms of BIM modelling - also proposing an operational modality to facilitate the drawing of BIM elements within the software - and finally reaching to the examination of three simulations which has been carried. This comparison can be useful to establish the current state of development of Freecad in the field of 4D BIM.