Flexible work location models, rethinking the neighborhood structure of large cities to improve the quality of living and working as well as other processes lead to an increasing need for more flexible building concepts that fit into existing city structures. Office and administrative buildings need to be flexible for changing requirements and need flexible usage options for the entire life cycle of the property. Modern timber structures can meet this requirement being modern, visually appealing and multi-storey to densify the neighborhood in grown city structures. Research focus is the development of a wide-span timber ceiling for multi-storey buildings without supports or girders within the slab span. Existing restrictions of conventional timber or timber composite slabs shall be lifted by variable floor plans with a high degree of prefabrication, simple joining technology and simple quality control. Support distances of around 12 m x 8 m should be achieved, which significantly exceeds usual reinforced concrete flat slab systems.