Presentation of the BIM produced for the renovation of the first skyscraper of Switzerland built in 1930 by Alphonse Laverrière. The project of the renovation was done by CCHE Architecture (Ehrensperger, Steiner, Cherix et al.). First, a digital model was produced to test the project according to the requirements of the authorities in terms of conservation. In the execution phase the Mechanical Electrical & Plumbing engineers were asked to produce digital models with their own CAD software and submit them in .IFC (Industry Foundation Class) format to the architects for coordination.