Parametric cost estimating model for conceptual cost estimating of building construction projects

It is well known that decisions at early stages of a construction project have the highest impact on the subsequent project performances. One of the bases for these important decisions is the project’s conceptual cost estimate. It is the first serious effort at attempting to predict the cost of the project. Conceptual estimates are made in the early phases of a project before construction drawings are completed, often before they are begun. The primary function of a conceptual estimate is to tell the owner about the anticipated cost, thus being useful information for the owner in contemplating the project feasibility and further project development. This research identifies building parameters that significantly influence the cost of building construction projects. The research presents methodologies for data collection, database development, data analyses, and parametric cost estimating model development for the purpose of performing building conceptual cost estimate. The data used in the model development and validation were based on the historical project data collected from the Texas Higher Education Coordinating Board (THECB). The data consist of 168 new building projects, built from 1990 to 2000. The technique of multiple regression analysis is used to develop the parametric cost estimating model by establishing the cost estimating relationships between the building parameters and the building construction cost. The purpose of this study is to develop a reasonably accurate and practical method of systematized conceptual cost estimating that can be used by organizations involved in the planning and execution of construction projects, such as THECB and the offices of facilities planning of the major universities in Texas. The concepts and methodologies presented in the study can also be readily applied to other similar organizations.