The development of an innovative, lean, mobile factory system to manufacture timber frame closed panels in temporary locations for use in the Assembly of Houses in the Affordable Rented Sector

(Embargoed until 1 August 2021) Generally speaking, timber frame construction is currently achieved through one of three methods: (i) Individual components such as lengths of timber, installation, waterproofing, external cladding is taken to site separately and are assembled together on-site. This is traditional construction. (ii) Sets of components are assembled together in the factory, and taken to site as prefabricated units. These prefabricated units are then put together on-site, with ancillary elements then added. This can be referred to as panelised or cassette-based construction. (iii) Volumetric construction refers to the assembly of completed rooms and spaces in the factory, with the completed unit or sub-units delivered to site to be craned into their final location. There are variants on each of these types but it is useful to categorise the three fundamental approaches this way. This thesis deals with the research proposition that a fourth alternative is possible and can have advantages in certain circumstances. The idea is that it is possible to develop a small, low cost, portable micro-factory that can be taken to a temporary location or a construction site and used to construct prefabricated closed panels remote of a fixed factory facility using either construction or non-construction operatives. The work augments on my previous research about using off site prefabrication as a means of delivering a sustainable housing system during a period of low morale and productivity in the house building industry (Gee, 2004). The social housing sector has provided the focus for this growing body of work and continues to do so. However, 20 years on since that original research was undertaken house building in the UK is still in a poor condition and still attempting to use prefabrication as a solution to the issues. This work proposes alternative less intensive approach to achieving the benefits of prefabricated housing without the infrastructure of using a fixed facility. A literature review of work on the condition of the construction industry in the UK since the millennium is undertaken. It considers initiatives where others have sought to implement learning in other industry sectors such as Lean manufacturing. Precedent studies of existing mobile technologies in construction and industries which are divergent are made. The review looks at closed panel construction systems used in house building. This research proposition is tested through the construction of a real-world, functioning prototype and associated operational processes based in Lean. The design, construction and testing of this prototype unit forms an essential and integral part of the experimental aspect of this thesis. The design of the unit is a result of a methodology that in part uses value stream mapping as a means of visualising solutions for the development of the prototype and as a means of achieving problem resolution during the design process. The information derived from testing the prototype unit as developed, contributes to the debate on the effectiveness of alternative methods of construction employed to produce housing and provides useful lessons for researchers interested in Lean systems.