A concept was to be found for a circumspect expansion of the existing church. The idea to simply break up the longitudinal wall and create a kind of protrusion was discarded. The planners felt that a transformation was only justified if it did not disrupt or disparage the late Baroque ambience, and decided in favour of an independent annex. This aim was achieved by employing a steel construction for the roof of the church that solved issues of both construction and design.