With the increasing size of 3D environments manual modelling becomes a more and more difficult task to perform, while retaining variety in the assets. The use of procedural generation is a well-established procedure within the field today. There have been multiple works presented within the field before, but many of them only focus on certain parts of the process. In this thesis a system is presented for procedurally generating complete build- ings, with an interior. Evaluation has shown that the developed system is compa- rable to existing systems, both in terms of performance and level of detail. The resulted buildings could be utilized in real time environments, such as computer games, where enterable buildings often are a requirement for making the envi- ronment feel alive.