Internal planning costs, comprising internal walls and doors, were found to be between 5.3% and 10.2% more expensive on the steel-framed options than on the concrete-framed option with the lowest floor-to-floor height, the post-tensioned flat slab. The flat soffits that are provided by precast concrete planks or in-situ concrete formwork will be easier to finish internal partitions against. Conversely, providing an acoustically “robust” head detail of an internal wall against a profiled deck or steel down-stand beam can be far more time consuming, both in initial installation and in subsequent re-work. Account is therefore taken of the added complexity of fire and acoustic sealing of partition heads against the irregular soffits of the steel decking and around the junctions of intersecting steel frame members. With approximately 3,000 linear metres of internal partitions, this is a significant factor. |