Development of openBIM based building code compliance checks: Case study in the City of Vienna

This study presents a structured, process-oriented methodology for developing and validating Automated Code Compliance Checking (ACCC) systems within real-world public-sector permit processes. The methodology addresses the challenge of systematically translating building regulations formulated in natural language into checking rules under legal and technical constraints. The proposed approach follows a four-phase workflow comprising evaluation of legal provisions, iterative development and testing, and pilot-based validation. A Regulation Information Matrix is introduced as a central methodological artifact to document legal interpretation, information requirements, implementation decisions, and validation outcomes, thereby ensuring transparency and traceability throughout the development process. The methodology was instantiated and evaluated within the BRISE-Vienna project, using openBIM standards and a rule-based checking environment. During the pilot phase involving 24 real construction projects and multiple BIM authoring tools, the approach was validated under heterogeneous modeling conditions. A representative regulatory requirement from the Austrian OIB Guideline 4 is used to illustrate the end-to-end workflow from legal interpretation to executable checking logic. The results demonstrate that ACCC can be operationalized in a reliable and transparent way when legal expertise, information modeling, and iterative validation are systematically integrated. This study contributes a transferable methodological framework that supports sustainable ACCC development within diverse regulatory permit contexts.