COST ESTIMATION WITH COST SIGNIFICANT MODEL ESPECIALLY FOR OFFICE BUILDING PROJECT

A variety of cost models are used in the world’s construction industries. InIndonesia, the use of traditional bill of quantity is common. Recently they are used aseffective and reliable cost models. This research explains the purpose of cost models, itexplain how the principle of costsignificance can lead to a simplified method ofmeasurement, which is both well structured and sufficiently accurate. The derivation of a cost significant model for 7 similar building projects ispresented by examples. The principle of obtaining the cost-significance method is applied by using Multiple Linear Regression Analysis, and the model has been tested by one similar project. The statistic data has been arranged and analyzed by using SPSS program. Thisprogram can produce the formula of multiple linear regression equations, the equationcan be used to make estimation of total cost for building projects. The result will be tested by different between estimated cost and actual cost divided to actual cost value. The result shows that the accuracy level reaches 5%-8%. The result provides the accuracy range of tender activity which is between 5%-15%. Keywords: Cost control, cost-significance, estimating practice, estimation method, multiple linear regression analysis, tender, estimator