Cost Changes in UK Design and Build Projects

The UK construction industry has seen many improvements over recent years, however one of the main ongoing issues is cost. Many projects face the problem of exceeding their initial budget resulting in unanticipated additional costs. It is important to avoid the client going over budget as this can ultimately affect the feasibility of a project. This research aim to investigate the factors driving cost changes in design and build projects within the residential sector in the UK construction industry. The gap in knowledge this study intends to contribute, is to investigate and proffer solutions to the causes of variance between contract sum and final account in design and build procurement option in the UK residential building projects. The research began with a brief literature review on different procurement routes and the factors which drive cost changes in construction projects. The findings of the literature review were used as the basis of the positivist research approach. The research used a mixed methodological approach, consisting of a questionnaire survey and semi-structured interviews to investigate the research problem. This research identified the design and build procurement route has succeeded in improving overall cost performance of construction projects by allocating the responsibilities of certain additional costs to contractors. However, despite these improvements, cost overruns are still problematic. Regardless of the chosen procurement route, complete design information at tender stage is essential to reducing cost overruns. This research established that subcontractors‟ performance ultimately depends upon the quality of site management. It is recommended to minimise any additional costs to a project, firstly design information should be complete at the time of tender and secondly the construction phase of the project should be managed by suitably qualified and experienced site management team. However, this study was limited to the residential building industry in the UK, hence further studies is highly recommended in developing countries as factors that causes this differences in contract sum and final account may be prioritised differently from the analysis within this study.