BIM-BASED SIMPLIFIED APPROACH TO AUTOMATICALLY ESTIMATE BUILDING COSTS FOR PROJECTS IN THAILAND

Abstract

Cost estimating is a significant and critical phase of construction projects. Traditional cost
estimating methods count on 2D drawings and human interpretation resulting in time-consuming and prone to
errors. Emerging Building Information Modeling (BIM) is a process that can enhance the quantity takeoff and
cost estimating with a higher level of accuracy. BIM-based cost estimating approaches can be done by
integrating 3D BIM with BIM-based estimating software. These approaches are complicated, expensive, and
required skilled-personnel to reap the full benefits from every estimating tools integrating with the external
database. This research presents a developed BIM algorithm that is capable of automatically estimating
building costs. 3D BIM intelligent objects were integrated with a custom built database with specialized
templates, thereby providing ease of use while eliminating the need to manually re-enter cost changes. This
algorithm creates a list of the specialized work breakdown structure (WBS) containing construction
specifications, and unit costs, based on the Thai standard system. A typical BOQ was generated from the 3D
BIM case study and linked to the specialized templates that automatically estimate building cost. Estimating
costs of the traditional and BIM-based approaches were compared and showed approximately closed value.
This research offers a simplified but essential BIM-based cost estimating algorithm for Small and Medium
Enterprises (SMEs) with a simple, fast and accurate process.