Lifecycle assessment and evaluation of construction and demolition waste management

The aim of this thesis is to test the hypothesis that by increasing the amount of waste material that is reused and recycled, the UK construction industry can become more sustainable. Construction waste reclamation is increasing as a result of demonstration projects, encouraged by the landfill tax and the impending primary aggregates levy. However, much of the recovered material is used for low-grade purposes and there is still a reticence to embrace its widespread use in higher specification applications as a direct substitute for primary materials. Applying sustainability principles to construction waste management requires a lifecycle approach whereby the social, economic and environmental impacts are considered of both the raw and secondary materials chain. Using data from a number of case studies, a lifecycle assessmenmt odel was created within which the impacts from five alternative waste management scenarios were compared. The impacts were evaluated using economic valuation and multicriteria techniques to provide an overall picture of the relative sustainability of the alternative options. Sensitivity analyses were used to test the validity and robustness of the results in the light of data uncertainty and other variations. The results suggest that managing construction waste further up the waste management hierarchy will result in a more sustainableU K construction industry. The financial costs follow a similar pattern, which raises the question of why recycled materials are not more widely substituted for primary materials. It is concluded that there may be additional factors that are difficult to include within an LCA such as market and information failures, the timing of materials supply and demand and industry confidence. Unless addressed, such factors will continue to limit the extent to which secondary materials replace primary materials in the industry and therefore the sustainability benefits that can be realised