Evolution of Japanese and British Prefabricated Housing Industry
From the ‘prefabs’ to nowadays
Comparing the UK and Japan is very provocative. They are so contrasting, but also share an incredible amount of similarities. One of those is the industrialisation of housing. After the second world war, both nations opt for similar ways of prefabrication of houses to overcome their heavy housing deficits. However, the outcomes after the years have been incredibly opposite. This article briefly narrates the evolution of both contexts remarking some examples.
After the Second World War, Japan and the UK needed housing to recover from the urban destruction produced by the war. Both countries initially opted for the industrialised process to overcome their substantial housing deficits. However, only Japan maintained a high percentage of its housing production through industrialised processes.
Despite presenting similar conditions in the first decade after the Second World War, the history of housing in Japan and the UK has followed opposite paths. These differences have been reflected in the housing volume that both countries have had during the years.
During the 1940s and 1950s, the first prefabricated house models were marketed in Japan. Examples of this era: the Junzo Sakakura and Kiyoshi Ikebe constructions systems that utilise industrialised elements and the Maekawa’s ‘Prefabricated Maekawa Ono San’in Manufacturing’ (PREMOS), which produce more than 1,000 units in total.
In the years following the Second World War, both countries had a severe need for housing caused by the destruction of their cities during the war.
By 1945, Japan had 63,000 hectares across 115 cities in ruins with 2.3 million destroyed houses, and with colonisers — Japanese troop soldiers sent to occupy countries during the Japanese colonial empire from 1895 to 1945 — coming back to the country, Japan had a shortage of 4.2 million houses. Destruction account for over 30% of their urban environment and most of them suffered over 50% destruction. The Japanese economy was unsteady, materials and labour were scarce, and supply chains were non-existent. Therefore, most of the houses built in Japan between 1945 and 1950 were self-constructed using residual war material, without the intervention of housebuilders. In contrast, the UK had industrial capacity and resources to set an immediate housing programme
However, in the UK prefabricated projects can be spotted from before. The London carpenter H. Manning was producing ‘Portable Colonial Cottages’ 5 in 1837. Between 1910 and 1930 the ‘Atholl Steel Houses’ company constructed over 100 houses and ‘British Iron and Steel Federation’ (BISF) houses delivered 36,546 houses designed by the architect Sir Frederick Gibberd and engineer Donovan Lee. These last two examples constructed on-site using factory produced steel frames. By that time timber housing was limited to the importation of houses from Canada and Scandinavia.
Eventually, from 1944 to 1949, in the UK the Temporary Housing Programme financed the construction of over 155,000 prefabricated bungalows, which were subsidised by the ‘Ministry of Works’ and manufactured by companies involved in other sectors. None of these companies continued producing prefabricated houses after the programme, neither other companies such as BISF. During the following decades, some housing companies utilised non-traditional construction methods but remained as conventional housebuilders.
The following image shows the positioning of an ‘AIROH’ — which stands for ‘Aircraft Industries Research Organization on Housing’ — Prefab house manufactured by ‘The Bristol Aeroplane Company Limited.
The Prefabs were initially promoted as temporary housing as a political strategy used to increase the public acceptance of unconventional means. Parallel to the Temporary Housing Programme, the Ministry of Works invested in the construction of permanent houses built with industrialised construction systems, also known as ‘non-traditional construction systems. Different from the Prefabs, these houses were assembled on-site using prefabricated components and commissioned to private contractors; where some of these were imported. There were multiple non-traditional construction systems; Wimpey No-fines, Easiform, The BISF, B1 & B2 Aluminium bungalows, Cornish Units, Airey, Reema Hollow Panel, Wates, Trusteel Mk II & 3M, Unity, Frameform and Quickbuild. Approximately 1,000,000 houses have been constructed in the UK using non-traditional construction system, which few remain in production.
However, in 1949, as part of the ‘Housing Act’, the Temporary Housing Programme was cancelled to give way to the private sector, which was not allowed to build houses for the ‘working class’ until that date. The Prefab production was dependant on government support, so once the programmes finished, the manufacturers based in the UK stopped producing houses and focused on producing for other sectors.
In the 1960s, housebuilding production in the UK was more than double current production. Housing production got evenly distributed between the private and the public sector. Local authorities were producing council estates, while the private sector was developing land through low rise housing.
Between 1963 and 1965, 85% of the Council’s building were high-rise, produced using 138 different prefabricated panel systems for multi-storey housing manufactured by 163 different companies. Industrialised construction systems were not exclusive to high-rise buildings. Local councils were using prefabricated components for most of their council estates, including mid-rise and low-rise housing. Even the private housing industry adopted some prefabrication systems for their housing developments.
By the end of the 1960s, high-rise buildings suffer public criticism for being unsuitable for young families, expensive to maintain, quickly deteriorating and dangerous, which was aggravated with the disastrous collision of the Ronan Point building. Consequently, in 1967, the government withdrew the subsidy for building high-rise buildings. That was a point that many people consider the end of the prefabrication of houses in the UK.
In different circumstances, most of the main Japanese housing manufacturers were founded during the 1950s and 60s. During the 1950s, the Japanese economy was rising due to economic support from the USA, which was focused on strengthening the industrial sector. Manufacturers invested in the production of prefabricated housing. Daiwa House began producing houses in 1955, PanaHome in 1959 and Sekisui House in 1960; all of which were funded as spinoffs of existing Japanese manufacturing companies and are still active today
The prefabrication of houses was led by Daiwa with their ‘Pipe House’ model in 1955. To Daiwa followed Sekisui House in 1960, Pana Home in 1963, Misawa Homes in 1967, SANYO Homes in 1969, Sekisui Heim in 1971 and Toyota started selling houses in 1977, all which remain active today.
This ‘boom’ came as a consequence of: the post-war housing deficit, expansion of Japanese industry in the housing market, use of laugh-steel in housing that came from an over-capacity in production after the Korean War, and due to the initiatives and promotion of the ‘Housing Loan Corporation’ and ‘Japan Prefabricated Construction Suppliers and Manufacturers Association’.
During the 1970s the Japanese government encourage the improvement of industrialised housing through the ‘House 55 development Competition’ and by exhibiting the Misawa’s ‘Home Core’ model at the Osaka Expo. The concept of prefabrication extends beyond housing and was reflected in many levels of architecture and construction, like in the Metabolic movement led by Kenzō Tange among others; in which, probably the most palpable example is reflected in the Nakagin Capsule Tower designed by Kisho Kurokawa.
In the early 1970s, Japan declared that the housing shortage carried from war times came to an end. house manufacturers started changing their business models from an agency system to a direct sales system to improve their customer service; and thus, quality. The production volume of manufactured houses grew dramatically during the 1970s and 1980s. By 1970, 137,000 factory-built dwellings were sold, counting for 10% of the housing starts that year.
Consequently, prefabricated house production in Japan reached a peak of 18% of the total market in 1994 and stabilised since then on 15% with an average of construction around 400,000 dwellings per year. The continuity and constant improvement of the Japanese housing companies have allowed them to refine their manufacturing processes looking for more precise ways to accommodate customers’ wants and needs as a marketing strategy.
The Japanese prefab housing evolution has come to very sophisticated outcomes. Today, their houses are produced at high-quality levels, in terms of resistance to natural disasters, thermal insulation and customisable designs.
The UK opted to turn back to traditional systems and use the technical aspects just to improve isolated sections of the procurement of houses. However, more and more often we listen to the argument that the “future” of housing construction is on imitating the car industry, just as the Japanese do.
The way ‘land’ is valued in both contexts is what has mainly caused that Japanese continue producing industrialised houses while the UK has opted for a speculative construction process.
The actual Japanese housebuilders are spin-offs of manufacturing companies, such as Toyota, and follow the business and manufacturing principles of their parent companies. Japanese housebuilders distinguish from each other regarding their business models and production processes, which from the client perspective is reflected in different cost, service and quality of the product. Innovation and control over production are very important; therefore, industrialised processes suit them perfectly.
Contrary in the UK, the industrialised housing sector was heavily supported by the government, it was not really a profitable business. Once the government stop funding the construction of prefabricated houses, their production ended.
It is common that all UK residential developers follow a business model based on speculation of land rather than on the production of houses. They prefer to keep their building processes stable and will only modify them to reduce costs. Housebuilders in the UK grow by expanding their land assets and by absorbing their competitors. They are basically only distinguished from each other in terms of location of their houses for sale, which will highly determine their cost.
The differences among both contexts are consequences of the socio-economic and cultural contexts. For Japanese mass customisers, high industrial capacity is a result of its particular historical and contextual characteristics. In certain times, the Japanese housing need was extremely high and industrial power was used to reach the needed production volume. Today, this housing need has been reduced. Housebuilders mass customise to extend their market coverage, and achieve the production volume that corresponds to their manufacturing capacity, and remain profitable. Japanese house manufacturers spinoff from manufacturing companies and has developed slowly, modifying with time to the values expected from house owners. As a result, the development of mass customisation in Japanese house manufacturers is independent of the adoption of machinery and technology. The levels of mass customisation observed in Japan are due to the use of lean and agile manufacturing systems, which are not strictly attached to investments in industrial machinery.
For house developers in the UK, land is the main asset. They invest, and had invested, in acquiring land as the UK possess land banks for urban development, different from the Japanese situation. Accordingly, the procurement and selling processes are designed around it. However, extensive land control by house developers has resulted in low competition and monopolised markets, where quality and customer involvement is diminished. Housing associations and small/medium scale housing manufacturers and developers are approaching off-site manufacturing as a strategy to compete in the housing market; while top house developers are allowing customers to personalise finishing details to sales and customer satisfaction levels.
The attraction to investing in manufacturing in the UK, in addition to the support of governmental entities to Modern Methods of Construction, imply risks not present in the Japanese scenario due to the difference in historic and land development conditions. Moreover, if housebuilders in the UK expect to achieve mass customisation, it is important to notice that Japanese investments in industrialisation were developed to achieve volume, not customisation. Japanese major investments towards mass customisation have been placed in marketing and selling infrastructure, including showhouses, information centres and selling centres. Thus, investments towards the implementation of mass customisation in the UK should focus on sophisticating marketing and selling infrastructure and strategies.
The Japanese house market is one example of how manufacturing is related to housing; and on how mass customisation leads to sustainable housing practices. The current attempts to push industrialised processes in the UK housing practice have not provided housebuyers with the benefits palpable in Japan — production consistency and efficiency, price certainty, high customisability, the inclusion of energy-efficient options, and more importantly a customer-oriented business.
The investment in machinery and technology in the UK is not applied to solve systemic issues present in the housing phenomena, as on how mass customisation is used in Japan. Modern Methods of Construction and Prefabrication are strategies used to solve only construction constraints. Important elements of the housing practice, like the approach to final users, co-design processes, and business profitability, are overlooked. In contrast, these elements are carefully considered by Japanese housebuilders holistically with the production processes.
Japanese housebuilders have not always been oriented towards customer satisfaction. The main house manufacturers in Japan have been present for over fifty years. Similar to how industrial machinery is currently applied in the UK, Japanese housebuilders firstly use it to solve construction constraints, particularly related to the housing deficit. The housing needs have drastically changed in Japan during these years forcing them to modify their housing processes. Housing deficit has been overcome, there is little land available for development and this is not increasing its value. Mass customisation has emerged as the only way to survive in the housing market. Conditions in the UK are very different. The housebuilding business remains driven by land ownership. The government is pushing the use of industrialised methods of constructions to break this condition; however, these are merely used by housebuilders to reduce construction costs.
Housing conditions in Japan and the UK are far for being similar. Socio-economic contexts and legislation play an important role in housing in conjunction with how land affects its practice. It is factual that conditions in the UK are shifting and that there is a possibility that the current drastic housing inflation could lead to a housing bubble burst. Similar to what happened in Japan in the 1990s. Housebuilders would need to modify shift towards customer-oriented practices to remain in business; or to prevent this phenomenon to occur. However, this is only a supposition, and the Japanese scenario might not be the same in the UK.
The use of mass customisation and customer-oriented practices is not dependent on housing conditions free of the effects of land control. Housebuilders in the UK could adopt these strategies to gain an advantage in the housing market, particularly in the rising niche of sustainable housing. The successful implementation of energy-efficient equipment and sustainable features in the Japanese houses is highly independent of legislation. In Japan, U-value regulations and carbon standards do not apply to most of the households (less than 300* square meters). They include these features and have developed inclusive construction/production systems because it is good for their business. It allows them to increase the number of houses they sell per year, or to position themselves in a higher market range and make more profit per unit. Both ways, it consists of a market strategy not exclusive of the housing practice; and therefore, feasible for the UK housing context. Prove of it, is that it is already present in the UK in other markets, like in the automobile industry.
Housebuilders in the UK would benefit from applying mass customisation strategies despite any shifting external factors. It is in their interest to apply fruitful business paradigms, particularly in the UK housing context dominated by the private industry.
There are more differences than similarities among both contexts. One of the main similarities is that both countries opted for prefabricated construction systems to overcome the housing crisis presented after the Second World War. Since then, the prefabrication sector has contributed to a fraction of the new housing stock in Japan; while in the UK, it was dramatically reduced after the termination of the Prefab programme and the collision of Ronnan Point.
This article pretends to set a background to understand the differences between the housing models in Japan and the UK. Without establishing these parameters the comparison of the housing models misses objectivity and fall into arbitrary conclusions. The comparison of both models require a background to understand the reason why these are as important as they are in their own context and why they are not (strongly) present in the other; particularly if there is an interest on adopting the technology observed in the Japanese housebuilding context, which might not result in a positive outcome.
But there is new hope for the industrialisation of houses in the UK with the arrival of new light technologies. Start-up private companies are looking back again to prefabrication as a promise to coup with raising challenges.
Both contexts (Japan and the UK) are taking different paths. The industrialisation of houses in Japan has been constant and keep on increasing their production processes, all based on the heavy industry; while the UK is re-starting to think about compact industrialised processes as an attempt to catch up with the standards and qualities observed in other places (like Japan).
