Abstract

Estimates for materials costs create significant variability in the final ‘as built’ cost of construction.  Getting estimates close to accurate from the beginning of a project reduces conflict, litigation and additional financing costs. Furthermore, accurate cost estimates go a long way towards ensuring the client is ultimately satisfied with the project on hand over.  Consequently, the task of identifying “best” supplier(s) of materials is central to construction procurement decision making.  The construction team needs to know who is most able to supply materials at the right cost, quantity, quality as well as with a high degree of certainty of delivery in order to achieve success.  Supplier selection is therefore a multiple criteria decision making (MCDM) problem. This study utilizes a five step research process; (i) to identify a comprehensive set of supplier selection criteria (SSC) by conducting a wide ranging literature review, (ii) to determine ‘vital SSC’ by applying ‘Pareto analysis’, (iii) to apply integrated AHP (Analytical Hierarchy Process) -BWM (define BWM) methods for understanding ‘best versus worst SSC’, from the given set of ‘Vital SSC’ by applying an AHP method to establish optimal weightings for each ‘Vital SSC’, (iv) to determine optimal weights for a given set of suppliers around each ‘Vital SSC’ using the AHP-BWM method, and (v) establish rankings for suppliers.  The proposed five step process is demonstrated by collecting the required pairwise importance score for the set of ‘Vital SSC’ and suppliers from 10 experts. The novelty of this study is to combine the MCDM methods: AHP and BWM in order to enhance the decision-making process and provide a more robust and comprehensive approach for SSP in construction projects.