Design, manufacture and construct procurement model for volumetric offsite manufacturing in the UK housing sector

The purpose of this study is to gain insight into procurement routes and forms of contract used for volumetric offsite manufacturing (VOSM) in the housing sector of the UK West Midlands. Seminal literature and government reports have established the potential of offsite technologies to improve the supply of quality housing in the UK. However, the lack of a structured procurement route, common to manufacturing approaches in construction, has significantly contributed to delays in large scale adoption. To achieve the research intention, an exploratory study was undertaken. A literature review of seminal literature and government papers was conducted to establish and benchmark current trends in context. Data was collected using focus groups and interviews with a housing association and housing VOSMs. Grounded theory was used to analyse data and inductively generate themes leading to an original procurement model. The issues identified in the delivery of volumetric housing were categorised into three themes. The findings suggest a limited familiarity with offsite manufacturing (OSM) by housing providers. Albeit, a willingness to adopt these technologies to deliver housing were demonstrated by trial attempts. However, due to limited knowledge, the approach to procurement is by adapting existing procurement models, which are not ideal and obstruct the potential benefits of using offsite technologies primarily because of the significant difference in processes. Also, geographical location influenced procurement decisions when comparing cost with conventional procurement and the dearth of specific government incentives to deliver housing using offsite technologies. This study proposes a procurement model for VOSM. Practical implications: The results have implications for decisions about procurement routes and contractual terms used by housing providers delivering volumetric offsite manufactured housing at scale. Although this study focussed on the West Midlands region, most of the issues identified were not geographically unique. This study contributes to the existing body of knowledge on potential barriers to the adoption of OSM in the housing sector of the UK. The findings will be of value to stakeholders involved in delivering housing and offers a useful contextual basis for future research.