Sustainable construction is about achieving a balance between the social, economic
and environmental aspects of construction so that the costs and the benefits, evaluated
along these three dimensions, are optimised. In the light of the huge expenditure of
the UK public sector on construction, the benefits that can be gained from integrating
sustainability into construction procurement can be very significant. The aim of this
thesis is to develop a theoretical framework to assist UK public clients in addressing
sustainability issues in construction projects' procurement strategies. The objectives include: (1) developing agreed sets of social, economic, and environmental
sustainability criteria that should be addressed by UK public clients in developing a procurement strategy; (2) identifying the factors that are important to better address
sustainable construction by UK public clients in developing a procurement strategy;
(3) identifying potential barriers (4) identifying the parties that are most capable of removing such barriers; (5) identifying whether or not local authorities are addressing sustainability in their procurement strategies, policies, guidelines and procedures; and (6) identifying how public clients are addressing sustainability in their procurement strategies, policies, guidelines and procedures. The components of the theoretical framework were derived from a thorough analysis of information obtained from a variety of sources (e.g. public sector practitioners, academics, professionals/consultants, and contractors) and throught the utilisation of a variety of research methods and techniques within a triangulated approach. These included (1) a Delphi Exercise in which 17 experts in sustainability participated, (2) interviews with 9 key professionals and experts, ( 3) a questionnaire survey to which 132 local authorities in the UK responded, and (4) two case studies of local authorities
demonstrating good practice in sustainable procurement. Triangulation was utilised
within and across the methods and the techniques adopted. It facilitated the access to different levels of reality, through combining qualitative and quantitative methods. Validation of the parts of the framework was conducted in several ways. These included validating the findings from each Delphi round in the subsequent round, validating the findings obtained from one method or technique by utilising another; and facilitating comments by the respondents/interviewees regarding any of the items included in the questionnaires/interview guides used in this research. (Continues...).