For John Miles of Arup's Advanced Technology Group, the route to successful prefab homes starts at designing a factory for the process, though convincing mass house-builders of the benefits of prefab will be a long job. Martin Pawley reports
'The key to successful prefabrication is to go into it like a product manufacturer starting a new line, not like a builder moving his operations into a shed.'
So says John Miles, leader of Ove Arup & Partners' Advanced Technology Group. He has made a special study of previous factory-made home projects, hundreds of which have failed over the last 80 years, and now he believes that he and his team are close to solving the problem. The difference between Miles' approach and that of his predecessors is that he and his team did not begin by designing a prefabricated house, but by designing a factory for making prefabricated houses.
Concept development took the form of production engineering, planning a two-shop single-storey panel factory with a floor area of about 4000m2 capable of turning out 10-12 fully equipped houses each day and trucking them to sites within a radius of 480km. If such a factory were rented, Miles calculates that it would need less then a million pounds-worth of equipment to get in business. If new build, less than £5 million. His views on the availability of such investment are refreshingly direct. 'Volume housebuilders spend a fortune on their land banks,' he says, 'but they won't put up £5 million or a million to start serious production. It is very difficult to break the status quo. The housebuilding industry has evolved to a position where it employs the lowest possible amount of capital. It has had a thousand years to refine this position. Putting up 'up-front' capital is an alien process.'
Miles' confidence that, given time, he can take on this sort of competition comes from his background. Trained as a chartered mechanical, rather than a structural engineer, he started out as a body-structure engineer in the motor industry. At Cranfield in the 1970s he worked on a computer program for crash-test simulation, designed a fire-engine safety cab, and investigated motor vehicle roll-over strength for the Department of Transport. After joining Arups in 1979 he analysed offshore structures and designed containers for radioactive waste that were tested in a dramatic high-speed locomotive crash that received wide publicity.
'That was when I first discovered that other industries were not as insular as the construction industry,' he recalls. 'The motor industry eventually responded very favourably and we were soon working on the computer analysis of vehicle impacts. This led to the application of the same approach to earthquake impacts on buildings, and thus a return to Arup's core business, structural engineering.'
Today Miles is a main board director at Arup, a firm where he insists almost any technological project can be studied. 'People here have the freedom to pursue what interests them. It's the best place in the world for active minds.' Because of this creative freedom Miles and his group have been able to develop their prefabrication ideas in a multidisciplinary way, with engineers, architects and car-design stylists working together. The influence of the car designers is to be seen in the interior treatment of the demonstration 'executive home' which the team is in the process of getting built as the next stage of one of its current projects. He concedes that this one-off structure will cost more than a conventionally constructed house, but he believes it will demonstrate the advantages of prefabrication and modularisation at a much higher level of refinement. 'Besides,' he adds, 'I have told the client I will buy the house myself once we have built it.'