Structural Redesign of a Multi-Family House into a Single Villa

For this project, we were entrusted with the structural transformation of a three-storey multi-family residence into a spacious single-family villa. The client, a former professional football player, envisioned a wide-open living space — requiring the removal of nearly all internal load-bearing walls. The existing structure posed significant challenges due to its hybrid composition. The eastern section, originally built in the 1930s, consisted of unreinforced masonry walls with timber floor slabs resting on aged building substance. In contrast, the western extension from the 1980s was constructed using sand-lime brickwork and reinforced concrete floor slabs. This required a detailed investigation of the masonry strength classes to ensure safe and reliable load transfer in the redesigned structure. To support the altered load paths, we introduced steel beams designed to carry both reinforced concrete slabs and timber floor structures — in some areas simultaneously. Some of the existing masonry walls remained above these beams, requiring strict deformation control. To avoid cracking or settlement, we limited beam deflection to L/500, equating to a maximum displacement of just 1 cm over 5 meters. One of the most complex tasks was designing the construction staging process. As load-bearing walls were removed, we temporarily supported both slab types using props and custom-fabricated metal sheets spanning the joint. The steel beams were then installed underneath, and gaps were filled with expanding mortar to achieve full bearing. After removing the temporary support, the remaining cavity was grouted to ensure continuous load transfer from slabs and walls above. Additional structural measures included: - Complete reconstruction of the gable roof in timber, with the integration of a full-length dormer. - Expansion of the existing terrace, improving outdoor living space. - Removal of a garage column, requiring structural reinforcement of the garage ceiling. This project demonstrates our expertise in handling complex renovation work involving mixed construction types, historical building fabric, and tight tolerances — all while ensuring stability during every stage of execution.