Building waste assessment score: design-based tool

Abstract Construction waste minimisation is a topical issue in many countries. The literature shows that the design has a major influence on waste. This study was undertaken to identify major sources of site waste generation in Singapore and to develop a model to evaluate building designs from the materials waste generation point of view. The paper is based on a survey of large Singapore building contractors. The principal finding is that four pre-determined attributes under ‘design’; three attributes under ‘operation’ and one attribute under ‘material handling’ were critical site waste sources. Multi-attribute value technique was used to develop the building waste assessment score (BWAS) model from respondents’ ratings on a five-point Likert scale that generated weights for the building sub-systems. The building design appraisal system developed by the Building and Construction Authority in Singapore was modified and used to build the BWAS model. It is recommended that designers should use the model to prepare designs which have less potential to cause site waste. Contractors may use the model to select site management techniques which help them to face the waste challenge posed by the design.