Analysis Model of Cost-Effectiveness for Value Evaluation of Building Elements

As various building materials have been developed, the combination of materials that make up the building elements has also increased exponentially. The materials making up the elements of the building will affect the performance of the building and the LCC. In order to improve the value of buildings in Korea, value engineering has been mandated in public construction projects with a project cost of over 10 billion won since 2000. The value index for systems (materials, elements, facilities, etc.) constituting buildings is calculated. However, the method for calculating the value index has not yet been normalized. The performance evaluation of the building systems (materials, elements, facilities, etc.) used in the current work and the method of calculating the value index for converting the LCC into a grade may vary depending on how the range of the grade is set. Even if the objects being evaluated are the same, there arises a problem that the results change depending on the value evaluation method. Therefore, this study tried to develop a value evaluation method that could draw consistent value evaluation results. For this purpose, this study presents a cost-effectiveness analysis model for the physical performance of the building elements and the value evaluation of LCC. Since the various physical performances of the building elements have different properties, normalization is required for comparison of physical performance values. In order to normalize the LCC and the 14 different physical performances of the building elements, a numerical model was designed using a linear transformation method and a vector normalization method. The cost-effectiveness analysis model proposed in this study was applied to two types of floor elements applicable to apartments in Korea, in order to evaluate the value and verify the consistency of this study’s model. The cost-effectiveness analysis model proposed in this study can help to derive reliable results when it comes to value evaluation for various existing building element compositions.