Prefabs in the United Kingdom

Prefabs were a major part of the delivery plan to address the United Kingdom's post–World War II housing shortage. They were envisaged by war-time prime minister Winston Churchill in March 1944, and legally outlined in the Housing Act 1944.
Taking the details of the public housing plan from the output of the Burt Committee formed in 1942, the wartime coalition government under Churchill proposed to address the need for an anticipated 200,000 shortfall in post-war housing stock, by building 500,000 prefabricated houses, with a planned life of up to 10 years, within five years of the end of the Second World War. The Housing Act 1944 aimed to deliver 300,000 units within 10 years, within a budget of £150 million.
Through use of the wartime production facilities and creation of common standards developed by the Ministry of Works, the programme got off to a good start and, of 1.2 million new houses built between 1945 and 1951 when the programme officially ended, 156,623 prefab houses were constructed. Today, a number survive, a testament to the durability of a series of housing designs and construction methods only envisaged to last 10 years. On the back of this scheme, local authorities developed non-traditional building techniques, which included some prefabrication, notably pre-cast reinforced concrete, to fulfil the underestimated demand.

Context

The combined effect of war and a lack of materials had a huge impact on the volume and quality of available housing stock. Contemporary estimates suggest that there was a shortage of 200,000 houses nationally. The result was the repeat of a strategy deployed by the government following the First World War, namely a country-wide investment programme in a national public house building scheme.
To tackle the problem Prime Minister Winston Churchill set up the cross-party Burt Committee in 1942, which sent British engineers to the United States the following year to investigate how Americaone of the main wartime advocates of prefabricated constructionintended to address its needs for post-war housing.
The outcome of the Burt Committee was that it favoured prefabricated housing as a solution to the problems. In a radio broadcast in March 1944, as the war in Europe was ending, Churchill announced a Temporary Housing Programme, known officially as the Emergency Factory Made or EFM housing programme. The vision was for a Ministry of Works emergency project to build 500,000 'new-technology' prefabricated temporary houses directly at the end of the war:
This vision and promise passed into law as the Housing Act 1944, which planned to build 300,000 prefab houses in Britain over the next four years, with a structural lifetime of between 10 and 15 years. In fact just over 150,000 were built.
By 1951 the EFM housing programme and its offshoots had created one million new council houses, resulting in 15 per cent of all the dwellings in Britain being state-owned, more than the proportion in the Soviet Union at that time.

Standards

The Ministry of Works created research institutes, standards and competition authorities that resulted in core building regulations.
All approved prefab units had to have a minimum floor space of, and be a maximum of wide to allow for transportation by road.
The most innovative creation of the Ministry of Works was what was termed the "service unit," something which they initially specified all designs had to include. A service unit was a combined back-to-back prefabricated kitchen that backed onto a bathroom, pre-built in a factory to an agreed size. It meant that the unsightly water pipes, waste pipes and electrical distribution were all in the same place, and hence easy to install.
The service unit also contained a number of innovations for occupants. The house retained a coal fire, but it contained a back boiler to create both central heating as well as a constant supply of hot water. For a country used to the rigours of the outside lavatory and tin bath, the bathroom included a flushing toilet and man-sized bath with hot running water. In the kitchen were housed such modern luxuries as a built-in oven, refrigerator and Baxi water heater, which only later became commonplace in all residential accommodation.
All prefabs under the housing act came pre-decorated in magnolia, with gloss-green on all additional wood, including the door trimmings and skirting boards.
To speed construction many were developed on the side of municipal parks and green belts, giving their residents, who had most often come from cramped shared rooms in inner cities, the feeling of living in the rural countryside.

Temporary Housing Programme

The Ministry of Works built a small estate off Edward Road, Northolt, in 1944 to demonstrate to the construction industry, parliament and the media the principles of their standards, and show that houses and flats could be built of concrete as well as brick. The highlight of the show was the live construction over two days of a Sir-Frederick-Gibberd-designed BISF house, under the watchful 24-hour eyes of the media.
The Ministry of Works then held a public exhibition of five types of prefab at the Tate Gallery in London, in 1944:

Two timber-framed designs, the Tarran and the Uni-Seco
One steel-framed with asbestos panels, the Arcon
One aluminium prefab, made from surplus aircraft materials, the AIROH

This proved so popular that the Tate held two follow-up exhibitions in 1945. In April 1945, in a public relations exercise, an Arcon was completed and handed over to its new occupants by 22 men in under eight hours, and in May an AIROH was erected on a bombed site in London's Oxford Street in just four hours.
While the cost of the prefabs was met directly by the Ministry of Works, the sites and utility infrastructure costs were the responsibility of the local authority. The 1944 Act had envisaged problems in obtaining access to sites quickly and hence slowing the programme, and so gave councils the authority to claim sites where two or more prefabs could be constructed. Councils were also given power over the site once identified, even before purchase was completed. The programme delivered quick housing, with properties going up at the rate in some authorities of 1.75 units per site per day, and the 100,000th house completed in January 1947 in Clapham, South London.
However, the cost of the programme at £150 million met with opposition at many levels, both politically and economically. In August 1945 the Portal was abandoned for lack of steel, while the Uni-Seco was effectively stopped from production from the middle of 1946 through lack of supply of wood. It was stated that both the Arcon and AIROH were above budget; the British prefabs in both manufacture and construction costs combined turned out to be more costly than traditionally built brick houses, while the American sourced units were cheaper. The population allocated prefabs were also concerned that prefabs were a permanent over a temporary solution, with the postwar radio comedy Stand Easy! with Charlie Chester creating popular skit-chants on the subject, including:
As the economy began to recover, the cost of the unwanted post-war excess production reduced and hence costs of manufacture rose sharply. When the Chancellor allowed the pound to float freely against the dollar from 1947 onwards, a programme costing 60 per cent of government income was severely cut back.
Production of the major types by local authorities continued until 1947, but only 170,000 of the 500,000 units promised were completed by 1951, when Churchill's new Conservative government took over. The prefab programme did not contribute greatly to the one million homes that the Attlee government succeeded in building.

Pre-cast Reinforced Concrete

Despite the construction of 156,622 temporary housing programme prefabs the United Kingdom still faced an acute housing shortage, and waiting lists soared in urban areas. Local authorities then took the lead in building new homes despite a shortage of materials and the hard winter of 1947. New estates were created and established ones expanded. To meet the shortage and bring the cost of housing down, a new form of construction was pioneered, commonly called 'PRC'.
Pre-cast Reinforced Concrete houses were largely made from concrete panels reinforced with steel then bolted together or constructed with a steel frame. They were quick to assemble and required less skilled labour than traditional build.
Different builders marketed new PRC designs such as the Airey, the Cornish, the Wates, the Unity, the Reema, the Tarran- a development of the Tarran THP design, the Woolaway and Parkinson types. The city of Leeds built the highest number of PRCs. They were similar to the prefabs in that they were built by non-traditional methods from components made in a factory but unlike the prefabs they were permanent, having a 60-year expected life.
The construction of these new quick-build houses seemed like part of the solution to the housing crisis at the time. From 1945 to 1955, 1.5 million homes were completed, relieving some of the housing demand. The percentage of people renting from local authorities had risen from 10 per cent in 1938 to 26 per cent in 1961.

Total production

Name	Programme	Sponsor	Designer	Frame	Walls	Roof	Bedrooms	Units	Cost of Construction	Notes
Airey				Concrete				25,567	£???
AIROH	EFM THP	Aircraft Industries		Aluminium	Aluminium or clad	Aluminium or Asbestos	3	54,000	£1,610	Could be erected in 4hrs. 675 sq ft
Arcon	EFM THP		Joseph Walsh		Asbestos		2	46,000	£1,209	Distinctive curved roof
BISF		BISF	Sir Frederick Gibberd	Steel	Steel/ Concrete	Steel	3+	31,516	£1,304 + £137
Cornish Unit				Concrete				23,173	£???
Howard							2+	1,404	£???
Laing "Easiform"		Laing	Laing	Concrete	Concrete	Clay Tile	2+		£???
Mowlem		Mowlem	Mowlem	Concrete	Concrete	Clay Tile	2+		£???
Newland & Kingston		Tarran Industries		Concrete			2+	2,681	£1,022
Orlit				Concrete				8,449	£???
Phoenix	THP	Laing	Laing			Steel plate over rolled steel poles	2	43,206	£1,200
Portal	EFM	Automobile industries								Original prototype 616 sq ft
Reema				Concrete				7,067	£???
Scotswood				Wood				1,067	£???
Tarran	THP	Tarran Industries		Wood	Pre-cast concrete				£???
Tarran variants		Tarran Industries		Wood	Pre-cast concrete				£???	A permanent house
Smiths Building Systems				Concrete				3,877	£???
Spooner				Wood				3,507	£???
Stent				Concrete				1,287	£???
Uni-Seco	THP							30,000	£1,131
Unity Structures	THP			Steel				13,701	£???
Wates				Concrete				18,776	£???
Woolaway				Concrete				4,845	£???
Wimpey "no fines"		Wimpey	Wimpey	Concrete	Concrete	Clay tile	2+	53,371	£???
All other steel frames				Steel				4,890	£???
All other in-situ				Steel				3,783	£???

NOTES:

LS - Precast Concrete, Large Slab
PP&P - ''Precast Concrete, Pier & Post''