Cost estimate system using structured query language in BIM

Abstract

Projects mainly fail due to inaccurate cost estimates. Building Information Modelling (BIM) provides an opportunity to utilize its database to develop a reliable cost estimate. The existing BIM-Based cost estimate tools rely on quantity extraction of design elements, then apply the cost. This practice has two limitations, first, it diminishes the spatial context of BIM elements, and second, the associated costs are derived from pricing the quantities, not the work items associated with BIM elements. This paper proposes a system to develop a cost estimate for building projects using a Structured Query Language (SQL). The approach leverages SQL to create an interoperable information management system that effectively transacts data with BIM elements. The proposed system harnesses BIM element parameters to drive work items associated with the parameter’s host element. The system applicability is illustrated by developing a cost estimate of a BIM element using the extracted quantities, work items, and methods of construction. The BIM-based cost estimate is compared with a manually prepared cost estimate for the same element. Both estimates are nearly the same, but the efforts to prepare a BIM-based cost estimate were substantially lower than the conventional method.