Within the context of a project, a software system is under development that supports the pre-planning of industrial halls using prefabri cated concrete elements. The goal of planning, using the software system, is a design that is stable and easy to implement in practice. It is therefore im-portant to use cross-sections that have a sufficient load bearing capacity and can be manufac-tured inexpensively and that the connections are planned such that they are easy to implement. The selection of suitable cross-sections and connections takes place with the aid of a knowledge base, which is not integrated in the source code but is kept separate instead. As a result of this, adaptation to various design standards or company-specific know-how is possible without having to make changes to the source code.