Regarding the constantly changing boundary conditions for the industrial creation of value, changeable factories must be challenged. Hence, the common factory planning process is enhanced by simulation techniques. Due to the increasing level of detail and complexity during this planning process, simulation models are characterised by an decreasing amount of changeability. In the prevailing work, the term changeability concerning factory planning and simulation is examined in further detail. For a mutual understanding, a cybernetic model of factory planning is developed. On this basis, three strategies for increasing the changeability of simulation models are depicted.