Towards code compliance checking on the basis of a visual programming language

In the AEC industry, there is a large number of standards and codes which ensure the structural stability, reliability, usability of the building under design. Accordingly, checking the conformity of the building design with these requirements is a crucial process. Nowadays this checking is performed to a large extent manually based on two-dimensional technical drawings and textual documents. Due to the low level of automation, the conventional checking procedure is laborious, cumbersome and error-prone. As Building Information Modeling (BIM) becomes more and more mature, a suitable digital information basis also becomes available to enable automating the process. The commercial solutions for code compliance checking available so far mainly follow a black-box approach where the rules that make up a certain regulation are implemented in a hard-wired fashion rendering their implementation in-transparent and non-extendable. A number of researchers have tackled this problem and have proposed various ways that allow the user to define rules, either in a standard programming language or in a dedicated language. However, AEC domain experts usually do not have the required programming skills to use these languages appropriately. To overcome this issue, we introduce the Visual Code Checking Language (VCCL), which uses a graphical notation in order to represent the rules of a code in a machine- and human-readable language. The paper presents the features and functionalities of the VCCL in detail and shows its application in a number of case studies.