A procedure to import a complex geometry model of a Heritage Building into BIM for advanced architectural representations

The aim of this communication is to present the advantages and disadvantages of a Scan-to-BIM process applied to a heritage building in order to obtain advanced technical drawings to be used in the analysis and illustration of the project. The whole process described includes: the survey planification and data acquisition with a Terrestrial Laser Scanner; the processing and cleaning of the point cloud; the 3D mathematical modelling; a proposal for semi-automatic modelling of organic elements; and the import of the final model into a BIM environment. Rhinoceros (McNeel) and Revit (Autodesk) are the main programs used. The crucial aspect of this workflow is found at the moment of importing the geometrical model into Revit, having to accommodate the criteria of this program in terms of tolerances, geometric structure of the solids, incompatibilities with NURBS libraries, etc. The result is a BIM model divided into families and subcategories where visual attributes can be assigned per element, parameterized and other visual information can be added (orthophotographs, wireframe analysis drawings, etc.). In other words, a 3D model from which highly configurable advanced representations (plans, vertical sections, perspectives, isometric exploded view, etc.) can be obtained and with which to generate analyses from the field of Architectural Graphic Expression.