Perkiraan Biaya Konstruksi Bangunan Gedung dengan Metode Cost Significant Model (Studi Kasus: Bangunan di Kota Pematangsiantar)

Abstract

One of the major challenges in the construction industry is cost estimation. Inaccuracies in the planning stage can lead to operational constraints, financial losses, and even the risk of project termination. Limited time and information availability in the early stages of planning mean that cost estimation cannot be done based on detailed work volume calculations, given that the details and specifications of the work have not been compiled completely. Therefore, an estimation model is needed that is able to provide accurate results based on minimal information. This research uses the Cost Significant Model (CSM) method, which is a cost estimation approach based on historical project data with a focus on the most significant cost components that affect total costs, and analyzed using multiple linear regression. The purpose of this research is to develop a cost estimation model for building construction in Pematangsiantar City. The data used comes from seven similar project packages in the 2018-2024 period. The analysis shows that there are four types of significant work (Cost Significant Items) with a cumulative contribution of 87.65%, namely: Reinforced Concrete (X3), Wall (X4), Roof and Ceiling (X6), and Floor (X5). The estimation model obtained is the equation Y = -1180589.554 + 1.144X3 + 3.347X4 + 0.955X6 + 0.871X5 with a Cost Model Factor of 0.9998. The accuracy of the model is in the range of -0.64% to 0.42% with an average of +0%. The value falls into Class 1 of the AACE International classification which has a lower limit of -3% to -10% and an upper limit of +3% to 15%. The estimation model is feasible to use for bid estimate checking.