Evaluation of slab and joist design on construction cost efficiency (case study: Office building)

Design phase is an important step in order to plan a construction project. One of the determining factors is the building economical value. In the design phase, a method or a design alternative with the most efficient economical value is needed without compromising on the strength of the structure. In this research, the case study is based on an office building. It represents a low rise building with a typical upper structural component which are columns, beams, and slabs with concrete material. Several design alternatives related to the efficiency of structural components' dimension will be analysed. This research is conducted through modelling the building structure by using the Finite Element Method. The calculation of the building structure construction cost will be evaluated for each design alternatives. The study shows that the most efficient design with joists reduction giving the cost reduction by 11.7%. On the other hand, thickening the slab and reducing the beam's dimension increase the cost by 26.9%.