Tiara United Residential development comprises two 49-storey residential towers with attached 11-storey car park. This unique and complex project involved complete architectural and structural redesign of the half-completed building from Hotel and Office to Residential towers. This process required modification and strengthening of the existing structure which was built until 18th floor, without major demolition work. The task involved major challenges to the structural design such as design and installation of the additional piles through existing raft which was needed due to the extension of the building footprint and strengthening of shear walls and columns. Structure is designed as steel/composite steel structure with RC core walls. Strengthening of the core walls was achieved by installation of steel plates and section enlargement.