The turn of the 19th and 20th centuries resulted in many new solutions in residential construction. The changes mainly concerned the style of the facades and the diversity of the building blocks. The functional layouts of flats were also adapted to new needs. Patterns from leading architectural centers were assimilated into smaller towns. In Bydgoszcz, which at that time belonged to the German Empire, thanks to the activity of well-educated architects and investors, buildings erected according to Berlin patterns appeared very quickly. The article examines the work of the architect Rudolf Kern who was active here at the beginning of the 20th century. The in situ research, analysis of technical documentation and comparative analysis showed that the architect, using both new stylistic and functional patterns and introducing technical innovations in his projects, as well as adapting it to the needs and tastes of residents, created works that contribute to the uniqueness of Bydgoszcz rental architecture.