The Internet of Things (IoT) is fragmented into many different smart environments, each requiring specific technical solutions for their use cases. This is a problem that has worsened over the years as new standards and technologies are constantly being developed. The term “horizontal integration” is used in literature to describe the attempt to reunite this fragmented IoT landscape. Abstract (in the sense of the OSI model) solutions are often proposed for this. However, the limitations of the underlying technologies are rarely sufficiently pointed out. This paper examines the integration of two smart environments as examples – the Smart Home and the Smart City. More specifically, it takes a theoretical look at how technologies can be connected between two Smart Home systems with the help of a Sma rt City technology and the problems that arise with it. ZigBee and LoRa are used for this purpose as exemplary technologies. Various possible application scenarios are shown to carry out a qualitative asse ssment of the feasibility of such a solution. The resulting problems of such an integration are shown and possible solutions for these are discussed.