The national standards for digital modeling are summarized in the separate digital standards group ÖNORM A 6241 These standards play a crucial role in defining basic techniques for the exchange and management of building information, which is essential in planning and property management for both building and civil engineering. ÖNORM A 6241-1:2015 "Digital building documentation - CAD data structure and Building Information Modeling (BIM) – Level 2" focuses on the technical implementation of data exchange and data storage of building information. It sets out the basis for the data transfer of CAD files and BIM and defines terms and representation principles.
In contrast, ÖNORM A 6241-2:2015 "Digital building documentation - Building Information Modeling (BIM) - Level 3-iBIM" regulates the technical implementation of a uniform, multidimensional data model for buildings. It creates the basis for comprehensive data exchange based on IFC and bSDD, in particular for the openBIM-Ansatz.
A central focus is on the ASI Property Server, which acts as a national property server. This manages properties such as descriptions, discipline affiliation and project phases and is linked to the international property server (bSDD). In the AVA process in particular (tendering, awarding, invoicing), the standard emphasizes the possibility of invoicing using models instead of traditional work contract standards, provided this is contractually agreed.
Furthermore, the dimensions of the virtual building model are highlighted, such as 3D for geometric and Alphanumeric information, 4D for time and construction planning, 5D for cost calculations and 6D for sustainability assessments. Reference is made to standardized performance descriptions according to ÖNORM A 2063 and the flexibility to carry out quantity take-offs and cost calculations according to the model is emphasized if this is agreed between the client and the contractor.