It is the purpose of the work to find out a new methodology for open BIM-based parametric library establishment.With the rapid development of computer technology,modern Computer Aided Design (CAD) systems generate feature-based product shape models with parameterization and constraints. However, standards for CAD data exchange among different CAD systems were restricted to the exchange of pure shape information in the context of the current technology. In the Architecture, Engineering and Construction (AEC) area, more and more attention is paid to digital methods of design and preservation on traditional houses. Unlike traditional 2D method, Building Information Modeling (BIM) offers an object-oriented and parametric digital representation way for traditional house components, an object-oriented parametric library could be established, and users need only to adjust the pre-defined parameters to their own needs in order to apply the components to their projects directly. However, recent researches mostly focus on certain software package; the parametric information cannot be exchanged among these kinds of BIM software packages even by open standard Industry Foundation Classes (IFC). This means that if users are to establish a library in BIM software A, the option to use parametric information from this library is unavailable to BIM software B using the current technology. Therefore each kind of software must have their own parametric library which causes extensive works. In view of the above limitations, the author developed an open BIM-based library for traditional house components. Open BIM means using advanced tools to manage a collaborative, interdisciplinary workflow process without limiting users’ choice of the electronic design and communication tools used. The research process is that: the author applied insight in the mechanical field, which applied a macro-parametric approach for parametric data exchange between different CAD systems, extended some commands in their XML Schema to parametrically represent traditional components. Since the XML technology has the advantage that it is a widely accepted format for data exchange and is suitable to open data implementation of application software, these XML files were then implemented in a browser which can be accessed by users for their component edit and selection in the Establishment of Korean Traditional House Component Library Project (EKTHCLP). After that, the author chose one component, parsed its XML file, and implemented a pilot Add-on User Interface in ArchiCAD for users to parametrically edit and direct utilization. Thus based on these XML files, both a browser can be implemented for users’ view and selection purpose and an add-on in ArchiCAD for users’ application purpose. In the future research, these XML files need to be implemented in other BIM tools. If the whole library was to be completed based on this XML approach way, an open BIM-based library would be established that all kinds of BIM software users could apply this parametric library for their easy modeling of traditional houses. This paper provides a new methodology for data interoperability and open BIM-based library establishment in the AEC field.The future research will focus on implementing more commands in the XML Schema to represent more kinds of traditional components; implementing the traditional component XML files in other BIM software packages; meanwhile, because the XML files are typed manually currently, a translator to automatically map the geometric information from IFC files to the XML files based on the XML schema is needed.