Abstract: Modern buildings are often equipped with universal bus systems. The purpose of these bus systems is to control the functions of houses such as lighting, climate control, and heating. In this paper we present a case study on how to build a home intrusion detection system based on data delivered by a house installation network. For this purpose we use anomaly detection in a similar way as in traditional network observing intrusion detection systems. We also present an example implementation utilizing outlier detection. Finally, we derive further research questions from the example implementation. Keywords: Home and building automation, Presence detection sensors, Intrusion detection, Outlier detection.