This paper describes a computer-based Interactive Biomimetic Space (IBS) installation. Through an interactive process, a user creates and relates new spaces. The simulation of a simplified ecosystem populates the created space with life. The installation attempts to inspire architectural design ideas by integrating biological principles. In particular, the biological concepts of stochastic motion, interaction and reproduction of artificial swarms have been explored and applied. Both the user and the swarm agents contribute to the design process, which results in interesting design outputs with a certain degree of unpredictability. We introduce the theoretical background of our work, outline its technical implementation, and present various interaction examples and scenarios.