Prof. Kahlen has been a freelance architect since 1977. Numerous significant projects have been planned under his direction and in various partnerships, including with Ingenhoven Overdiek Kahlen und Partner; these projects have largely been resulting of won competitions.
The results of a number of years of applied research by Prof. Kahlen in the area of holistic construction, integral facility management and computer application in architecture have been developed in two research institutions that he has founded and the results from these have been integrated into the respective construction processes of major projects.
J. J. Kahlen gained his doctorate from the University of Dortmund in 1990 and thereby deepened his knowledge particularly in the area of the management tasks of architects.
In 1993, after his cumulative habilitation, J. J. Kahlen was appointed as a full professor at Brandenburg Technical University. The progress of scientific tasks in the area of construction processes is a primary concern of Prof. Kahlen, alongside the focus on planning. As well as the distinction as a scientist, numerous national and international construction projects – which have often been planned and constructed in partnerships – have also won prizes and awards.
In many publications, book projects and presentations, Prof. Kahlen has documented his scientific findings from the areas of construction and integral facility management and he has made these available particularly for training, education and study.