The Building Information Model and the IFC standard: analysis of the characteristics necessary for the acoustic and energy simulation of buildings

The new European Directive 2014/24 / EU requires for all member States the use of BIM procedures in the construction of public buildings. The countries belonging to the European Union shall be obliged to transpose the Directive and adapt their procedures to that effect. The paper analyzes the IFC format, the only recognized by the European Directive Standards for BIM procedures, in order to assess its use for simulations of buildings. IFC, described by the ISO 16739 (2013), is today a standard that describes the topology of the constructive elements of the building and what belongs to it overall. The format includes geometrical information on the room and on all building components, including details of the type for performance (transmittance, fire resistance, sound insulation), in other words it is an independent object file for the software producers to which, according to the European Directive, it will be compulsory to refer in the near future, during the different stages of the life of a building from the design phase, to management and possible demolition at the end of life. The IFC initiative began in 1994, when an industry consortium invested in the development of a set of C ++ classes that can support the development of integrated applications. Twelve US companies joined the consortium: these companies that were included initially are called the consortium "Industry Alliance for Interoperability". In September 1995 the Alliance opened up membership to all interested parties, and in 1997 changed its name to "International Alliance for Interoperability". The new alliance was reconstituted as a non-profit organization, with the aim of developing and promoting the '' Industry Foundation Class "(IFC) as a neutral data model for the building product that were useful to gather information throughout the life cycle of a building facility. Since 2005 the Alliance has been carrying out its activities through its national chapters called SMART building. The present study aims at evaluating the IFC, comparing the information and data contained in it, with other formats already used for energy simulations of buildings such as the gbXML (Green Building XML), highlighting the missing required information and proposing the inclusion of new ones to issue the energy and acoustic simulation. More generally the attention is focused to building physics simulation software devoted to exploit the BIM model potential enabling interoperability.