System Building and Aesthetic Preference

CONTENTS

Declaration

List of figures

Acknowledgements

Introduction

Chapter One - Historical review

Chapter Two - Current uses
Systems available
Benefits of system building
Key issues in the system building method
Perceptions of value and aesthetics
The image of system building
Flexibility and services
Procurement

Chapter Three - Perceptions and attitudes towards system building
General image
Perceived performance
Public expectation
Perceived value
System building awareness

Chapter Four - Aesthetics and Psychology
Perception
Aesthetic
Vagueness
Vague notions to physical concepts
Feelings
Attributes for assessing preference

Chapter Five – A study examining attitudes towards various house types using system building
Methodology
Results

Chapter Six - Conclusions and recommendations

References

Appendices

Declaration

I hereby declare that the work presented in this Dissertation has been composed by myself and has not been accepted in any previous application for a Degree. All quotations have been indicated by quotation marks, and all sources of information specifically acknowledged at the end of this Dissertation.

Title of Dissertation: System Building and Aesthetic Preference

Signature:

Name: Razak Basri

MSc. in Advanced Architectural Studies

Date: 28-9-2007

List of figures

Fig.1 The garden of this ARCON model has been slabbed for convenience, but the prefab remains a treasured home. (Vale, Brenda, Prefabs: A history of the UK Temporary housing programme, 1995).

Fig.2 This temporary housing has been re-modelled and extensively refurbished. A pantile roof has been added and the wall has been plastered and finished with a new coat of paint. (Vale, Brenda, Prefabs: A history of the UK Temporary housing programme, 1995).

Fig.3 Temporary Housing Programme prefabs was popular with their occupants. Despite extensive upgrading and modernisation, this example is still recognisable as a prefab. (Vale, Brenda, Prefabs: A history of the UK Temporary housing programme, 1995).

Fig.4 The CLASP system based on lightweight steel was used for school construction in the 50’s. (White, R.B. (1965) Prefabrication- A history of its development in Great Britain, Ministry of Technology, Building Research Station, Her Majesty’s Stationery Office, London 1965).

Fig.5 Wall panels joined to form accommodation unit. (Glass, Jacqueline. (1999) The future for precast concrete in Low-Rise Housing. British Precast Concrete Federation, 1999).

Fig.6 Speed of erection on site results in early completion. (Glass, Jacqueline. (1999) The future for precast concrete in Low-Rise Housing. British Precast Concrete Federation, 1999).

Fig.7 The efficiency of factory based production methods.

(Glass, Jacqueline. (1999) The future for precast concrete in Low-Rise Housing. British Precast Concrete Federation, 1999).

Fig.8 High quality typical wall units in manufacturer’s stockyard. (Glass, Jacqueline. (1999) The future for precast concrete in Low-Rise Housing. British Precast Concrete Federation, 1999).

Fig.9 A precast concrete staircase as a separate component is being placed on-site. (Glass, Jacqueline. (1999) The future for precast concrete in Low-Rise Housing. British Precast Concrete Federation, 1999).

Fig.10 Precast hollow core panels being installed on site. (Glass, Jacqueline. (1999) The future for precast concrete in Low-Rise Housing. British Precast Concrete Federation, 1999).

Fig.11 Modular precast unit being lifted to form multi-storey apartments. (Glass, Jacqueline. (1999) The future for precast concrete in Low-Rise Housing. British Precast Concrete Federation, 1999).

Fig.12 An estate of Arcons at Newport, South Wales, each carefully positioned to gain maximum benefit of a south-facing slope. (Vale, Brenda, Prefabs: A history of the UK Temporary housing programme, 1995).

Fig.13 System building is cheaper and faster than traditional construction, especially in the case of multi-unit dwellings like this one. . (Davies, Colin (2005). The prefabricated home. Reaktion Books).

Fig.14 System building is not necessarily associated with monotony. Although it is important to have standardization, the façade can be treated in many ways to enhance aesthetic quality, as in this housing project. (Davies, Colin (2005). The prefabricated home. Reaktion Books).

Fig.15 Architects will have to consider crucial questions of what architectural aesthetics mean how it can be interpreted and how architecture should be perceived in relation to system building. (Davies, Colin (2005). The prefabricated home. Reaktion Books).

Fig.16 At first glance, they may all look alike, but the designer’s innovative apartments allow for a high degree of customization. (Davies, Colin (2005). The prefabricated home. Reaktion Books).

Fig.17 Could these housing apartments be the future of system building in Britain?

(Davies, Colin (2005). The prefabricated home. Reaktion Books).

Fig.18 The high aesthetic design transforms the notion of ‘affordable housing’ into something people are happy to live in. The building’s success with tenants has resulted in numerous new commissions for similar fabricated housing scheme for the architect. (Davies, Colin (2005). The prefabricated home. Reaktion Books).

Fig.19 Design A- Multi-Storey social housing. (Design for Homes (2007) available from:www.designforhomes.org)

Fig.20 Design B- Semi-detached housing estates. (Sergison Bates Architects (2007). Design B - Stevenage housing project, London).

Fig.21 Design C- Up-market apartments. (Richard Rogers & Partners (2007). Design C - Montevetro project at Battersea, London).

Fig.22 Percentage of age group. (Prepared by Razak Basri using SPSS and Microsoft Excel).

Fig.23 Bar chart showing general aesthetic preference based on responses. (Prepared by Razak Basri using SPSS and Microsoft Excel).

Fig.24 Graph showing design preference for non-students. (Prepared by Razak Basri using SPSS and Microsoft Excel).

Fig.25 Graph showing design preference for students. (Prepared by Razak Basri using SPSS and Microsoft Excel).

Fig.26 Bar chart showing gender (male) on design preference. (Prepared by Razak Basri using SPSS and Microsoft Excel).

Fig.27 Bar chart showing gender (male) on design preference.

(Prepared by Razak Basri using SPSS and Microsoft Excel).

Fig.28 Graph showing the comparison between ‘scheme appearances’ with ‘aesthetically appealing’ responses. (Prepared by Razak Basri using SPSS and Microsoft Excel).

Fig.29 Graph showing profession (non-students) on consider buying the house. (Prepared by Razak Basri using SPSS and Microsoft Excel).

Fig.30 Graph showing profession (students) on consider buying the house. (Prepared by Razak Basri using SPSS and Microsoft Excel).

Fig.31 Bar chart showing the result of design preference. (Prepared by Razak Basri using SPSS and Microsoft Excel).

Acknowledgements

The author wishes to express his appreciation and acknowledgement of the help and courtesies afforded to him by Dr. Anthony Craig who regularly lends his advice, guidance and his invaluable opinions. The appreciation also goes to the library staff who consistently assist me in finding research materials and finally to someone who wants to remain anonymous.

INTRODUCTION

This dissertation is concerned with the aesthetics of architecture using system building in housing in the UK. It has been produced in response to a growing level of interest in the system building method and in the aesthetic value of housing schemes constructed using the system building method.

The aim here is to consider research on the system building methods within a house building context and test different types or categories of housing schemes based on aesthetic preference. This study explores issues of perception and level of aesthetic value.

In general, aesthetics is the study of the psychological responses to beauty and artistic experiences.

Aesthetics is the branch of philosophy which deals with the nature of art and of artistic judgment. Some of the central questions of aesthetics focus on the beautiful: under what circumstances it may be said to exist, what criteria are to be used to judge the beautiful, and whether or not these criteria apply equally to literature and music.

There are two traditional views concerning what constitutes aesthetic values. The first finds beauty to be objective, that is, inherent in the entity itself. The second position holds that beauty is subjective, in that it depends on the attitude of the observer. Immanuel Kant argued that judgments of taste, as he called aesthetic judgments, rest on feelings, which, though subjective, have universal validity. The instrumental theory of value, an extension of subjectivism, holds that the value of art consists in its capacity to produce an aesthetic experience (Kristen L. Zacharias).

System building leads to a faster completion period, well organized site, and better quality workmanship and most importantly offers major cost benefits for clients, architects and builders (Basri, 2006). This also means that the construction method is simplified and standardised and ensures good communication between the parties involved (Fergusson, 1981). For the purpose of this study the concept of system building is to be understood in its widest possible context. This dissertation is in six chapters.

Chapter one focuses on the use of system building, and considers the history of the system building method in housing, including the Ronan Point incident. Clearly there is an argument that system building has a reputation which to some extent continues to prejudice its use in housing. The chapter reviews the origins of system building and also the effects of industrialisation on the building industry, in a process moving towards the factory production of building components. It explains the historical background and offers an overview of the development of the system building method from the early part of the twentieth century, through the two World Wars, the post-war period which led to a revolution in the building industry, until today.

Chapter two examines the various types of system building available in the market generally. The benefits of the system building method, speed and quality are included together with a discussion of cost and value issues. Indeed, take-up of system building may ultimately depend on the balance of construction costs and added value. This difficult equation may need to be resolved on an individual project basis, thereby offering every house building client a bespoke package. For system building to make inroads in the housing market, contractors and clients need to be made aware of the speed and quality benefits it offers, while owners and occupiers need to be made aware of the performance benefits over time such as thermal mass. Other considerations such as services integration and adaptability are related to the future needs of occupants, and procurement strategies are noted.

This chapter also focuses on the broader issues that could affect the take-up of system building in housing. The findings from recent surveys of the public, house builders and housing associations are presented. There is a body of opinion that supports the notion that traditional materials are the most appropriate and popular for new housing in the UK, but there is also a growing interest in different styles and ways of living, particular in urban areas. The surveys presented here suggest that the UK continues to prefer heavyweight construction. A discussion of the influence of other market drivers is given; the Egan report and sustainability could have significant impact on the way in which all housing is procured in the future. This Part of the chapter also contains an account of the current market success of other materials in the prefabricated housing sector. Although steel and timber are used, recent surveys indicate that the public seems not to be particularly keen on system building method buildings in general.

Chapter three discusses perceptions and attitudes towards system building. It explains why system building has often been perceived negatively by the public both in terms of general image and performance. Other perceptions and attitudes such as client expectation, perceived value, industry culture and system building awareness are also discussed in this chapter.

Chapter four explores the importance of perceptual psychology in considering the aesthetics of an object, specifically in architecture. Reviews of the relevant literature introduce the issue, which is considered more fully in the following chapter.

Chapter five examines attitudes towards various house types constructed using system building based on case studies (3 types of dwelling). It describes the methodology used to explore this and includes an analysis of the results obtained. This chapter is important in determining aesthetic preference in the different types of housing built using a system building method. From this study it is expected that the outcome of aesthetic attitudes towards these three categories of housing schemes constructed with system building will be consistent. It is predicted that design C will be the most preferred because of its high quality architectural design and materials composition.

Finally, chapter six includes conclusions and recommendations.

CHAPTER ONE – HISTORICAL REVIEW

Russell (1981) mentions that it is very important to understand the relationship between the histories of system building as opposed to traditional construction. He says “an obvious question for the architectural historian is whether there was such a thing as a style distinctively that of system building as opposed to other methods of construction”. To try and answer this question it is helpful to examine the historical development of the construction industry in relation to system building and how it has been and continues to be influenced by changing social, political and cultural values (Basri, 2006).

The history of construction for system building started in early part of the twentieth century. There are many examples of its use however, which predate this such as the first Iron Bridge in the UK, which was built at Colebrookdale in 1779 (White, 1965). Other early activity includes the export of houses, churches and hospitals to the colonies such as West Indies, Africa and Jamaica in the middle of the nineteenth century (White, 1965).

The importance of the system building method became greater during the first half of the twentieth century due to various factors relating to the two world wars. These factors included low production of housing during the wars, returning soldiers needing a decent place to live and traditional techniques being unable to cope with the surge in demand.

The ability of what was left of the house building industry to respond to these demands was very limited. There was an inevitable shortage of both traditional materials and skilled personnel after both wars (White, 1965). These circumstances created the climate for looking again at how and with what materials housing could be built to meet the country’s need.

The government had already realised during WW1 that rebuilding would be an issue and formed a Ministry of Reconstruction in August 1917. The Ministry was given the brief:

“To consider and advise upon the problems which may arise out of the present war and may have to be dealt with on its termination” (Phillipson, 2001, p3)

Early attempts at system building were not a great success possibly because they concentrated on replacing bricklaying with concrete. Although the new method had been able to provide some additional homes, it had not been able to make any significant impact on the house building industry and had more or less come to a standstill by 1928.

There was a shortage of housing stock following the Second World War due to destruction by bombing and the lower priority given to new building works during the hostilities. Therefore, there was a need for the problems to be solved as quickly as possible. There was great political pressure to provide homes for returning soldiers. Churchill (1944) mentioned by Vale (1995, p23) in Basri (2006) announced the launch of a temporary housing programme at the end of the war to meet the immediate needs of returning soldiers. He said that “the soldiers when they return from the war and those who have been and made to double up with other families shall be restored to homes of their own at the earliest possible moment”.

Since the munitions factories were no longer in full production for the war effort it was felt that they could be useful in helping to solve the housing shortage. They were therefore adapted to fabricate parts of houses that could then be quickly erected on site. This involved a lot of effort by designers and manufacturers as the materials required, such as timber and brickwork, were different from that used in manufacturing armaments.

Recommendations for post-war housing construction were made by the Burt Committee (Vale, 1995) which considered materials and methods of construction, taking into account efficiency, economy and speed of erection.

The work of the Burt Committee (White, 1965) led to an increase in the number of non-traditional properties being built in the UK. This included timber frame houses, which were imported in significant numbers.

Although system-built timber frame dwellings had been gradually introduced into the United Kingdom from the 1920s they had not been important in such numbers before.

The shortage of timber led to forms of rationing with standards limiting section sizes and where timber should be used in house construction. This meant that timber sections of systems built after 1945 were often smaller than had been used before and even during the Second World War. After 1945, innovations were introduced including the use of separate claddings usually brick, with a cavity behind, stressed skin panels and systems in which whole units were made in the factory and then put together on site (Phillipson, 1998). If there had been no rationing the prefabricated timber system would no doubt have been more commonly used but it was not until 1953 that rationing came to an end.

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Fig.1 The garden of this ARCON model has been slabbed for convenience, but the prefab remains a treasured home. (Vale, Brenda, Prefabs: A history of the UK Temporary housing programme, 1995).

After the Second World War a new type of state-subsidized house appeared in Britain. The two-bedroom temporary bungalow was produced ostensibly to provide much needed housing in the immediate post-war period and some 156,623 houses were supplied through 1945-1949 as part of the scheme (Vale, 1995). This is significantly less than the numbers expected by the programme. This gap between expectations and actual provision has contributed to the perception of a poor programme.

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Fig.2 This temporary housing has been re-modelled and extensively refurbished. A pantile roof has been added and the wall has been plastered and finished with a new coat of paint.

(Vale, Brenda, Prefabs: A history of the UK Temporary housing programme, 1995).

The government then embarked on a massive housing programme assisted by architects, manufacturers and builders (Vale, 1995). From 1966 to 1975, system-built housing was widely used in the public sector.

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Fig.3 Temporary Housing Programme prefabs was popular with their occupants. Despite extensive upgrading and modernisation, this example is still recognisable as a prefab. (Vale, Brenda, Prefabs: A history of the UK Temporary housing programme, 1995).

In the late 1950's the program to provide increasing numbers of housing units within a very short space of time and making the maximum use of restricted site space was intensified. These restrictions as well as cost factors led to the introduction of Large Panel Systems Construction in the UK, using existing technology first developed in Denmark in 1948. One such system was the Larsen Neilsen system and Taylor Woodrow - Anglian Ltd was the United Kingdom licensees (Phillipson, 1998).

In 1963, the first such building in the UK was constructed for London County Council. In 1965 the London Borough of Newham commissioned nine twenty-two storey Larsen Neilsen blocks.

But disaster struck in 1968. Work had begun in 1966 on the now infamous Ronan Point block. It was the second to be completed and was handed over on the 11 March 1968. At 5.45 am on Thursday 16 May 1968 there was an explosion that caused great damage both to the building itself and to the image of system building as a whole.

There have been other problems associated with these systems, such as condensation, leaking joints etc., but these are rather a result of poor workmanship rather than design; they have however left a perception among many of prefabrication being associated with poor quality buildings (Phillipson, 2003). The specific problems at Ronan Point were not all related to the form of construction. The publicity however has been closely associated with the method of building and has again contributed to a negative view in some quarters of prefabricated forms of construction (Phillipson, 2003).

The other important structures associated with system building such as schools, community centres etc have many requirements. These buildings have different construction needs and are more diverse than those of housing. The use of prefabrication technology is well established and there continues to be considerable scope for future development.

UK schools have long been constructed using system building. After WW2 the country was under pressure to return to normal but was suffering from a lack of resources and skilled labour. The Hertfordshire schools programme was an outstanding example of a programme which used prefabrication technology to meet the local pressures from the expansion of London and the establishment of post war new towns (Hatfield, Hemel Hempstead, Welwyn Garden City, etc) that were driving the need for schools. Particular systems of prefabrication developed for school construction in the 1950’s include the Intergrid system, using precast reinforced concrete columns and beams to form the structure (White, 1965), and the CLASP system based on lightweight steel (White, 1965). The ‘Intergrid’ system in particular was widely used, and many school buildings that were erected with this system are still providing satisfactory school buildings today.

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Fig.4 The CLASP system based on lightweight steel was used for school construction in the 50’s.

(White, R.B. (1965) Prefabrication- A history of its development in Great Britain, Ministry of Technology, Building Research Station, Her Majesty’s Stationery Office, London 1965).

The situation is somewhat different in the commercial sector as compared to the housing sector because it is important for commercial clients to begin trading as quickly as possible in order to recoup construction costs and maximise profit. Therefore, commercial clients have been willing to adopt ‘fast track’ construction methods and have been much more positive as regards system building, which has been seen by many as the route towards achieving a faster completion time. McDonald’s Restaurants use prefabrication technology (Phillipson, 2003) to build their new out-lets; recently they set their record of a completed outlet being built and open for business within 13 hours of starting construction on prepared ground works. The financial advantages for commercial clients are considerable and therefore many businesses from hotels to retail outlets are adopting some form of system building.

The success of the system building method in non–domestic construction in the UK has led to the further development of other systems for successful housing projects such as the Joseph Rowntree Foundation (social housing), the William Sutton Trust (affordable housing) and many more. The perception of system building may be therefore undergoing significant positive change.

CHAPTER TWO – CURRENT USES

Systems Available

There are wide varieties of forms and applications of system building currently being used in the United Kingdom. These range from the simple prefabricated site hut, which has been a long established application, up to volumetric units that can be delivered to site to integrate into the structure of the building. More difficult to define are the prefabricated components that are available and can be combined to become part of the structure, standard components are available as well project specific components. Types of system building approaches that can be used include:

Prefabrication

- Monolithic unit
- Lightweight units
- Heavyweight or volumetric

Components

- Total Systems: Panels
- Open Production
- Closed Production
- Structural Systems: Frames

Poured In-Situ or Cast In-Situ

- Total system formwork
- Climbing System Formwork
- Lift slab
- Slip Form
- Tunnel Form
- Table Form
- Flying Form

Modularization or modular design has been described as the key to prefabrication (Paulick, 1966). Modular design refers to construction using standardised units or standardised dimensions. Modular buildings do not have to be built using prefabrication techniques, but they are usually involved.

One aspect of system building in the UK is that of frame construction, in particular timber frame. This is well-established in Scotland and is the market leader in house construction. However, this has not been the case in England and Wales. The traditional systems there are masonry systems and this, along with a World in Action report in 1984 which dealt with problems in the timber-frame construction industry, probably accounts for the difference. Tighter Thermal Regulations, though, are resulting in a greater development in the timber-frame market and some factories manufacturing timber-frame systems are now operating in the UK (The Traditional Housing Bureau MORI survey, 1999). In housing, timber-frame systems are usually small panel wall systems. Volumetric construction products, however, are also beginning to be produced.

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Fig.5 Wall panels joined to form accommodation unit. (Glass, Jacqueline. (1999) The future for precast concrete in Low-Rise Housing. British Precast Concrete Federation, 1999).

Another important aspect of system building concerns the plant and services of a development. The Building Services Research and Information Association (BSRIA) have recently completed a DETR study (2001) into the application of prefabrication to services. This compared system building with traditional methods and looked at some of the determining factors in a successful approach.

The adoption of system building in the UK has been intermittent, and usually dominated by the bigger companies. It is they who have been keenest to experiment with using prefabrication and standardisation techniques in order to improve productivity in the construction industry. These developments have usually taken place in larger urban environments, where the economics of site time dominate.

Benefits of the System Building Method

Financial and commercial building owners developing valuable city sites demand the quickest possible returns on invested capital. For them, speed of erection and finish are of paramount importance (White, 1965). The system building method reduces the time spent working on site and also reduces the impact of the building site on the local environment. This offers, therefore, both financial and environmental benefits. Most of the components are pre-assembly and manufactured off-site. According to a report for the Construction Industry Institute (CII) in the USA, Tatum et al. (1986) cited by Gibb (1999, p1) defines “Pre-assembly is a process by which various materials, prefabricated components, and/or equipment are joined together at a remote location for subsequent installation as sub-unit. It is generally focussed on a system”. By using system building, the site will be vulnerable to bad weather conditions for less time, and the project will be subject to less delay and requirements for protection.

Major retailers are using the system building method to reduce as much as possible the project time, in particular time spent on site. Some believe that as much as 50% savings in project time is a realistic target. (Glass, 1999)

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Fig.6 Speed of erection on site results in early completion. (Glass, Jacqueline. (1999) The future for precast concrete in Low-Rise Housing. British Precast Concrete Federation, 1999).

The UK market is now beginning to use some European systems (such as thin joint masonry products) in fast track construction. This enables the quick erection of a weather-tight shell, which means that the internal work can be carried out in any weather conditions.

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Fig.7 The efficiency of factory based production methods. (Glass, Jacqueline. (1999) The future for precast concrete in Low-Rise Housing. British Precast Concrete Federation, 1999).

Implications for the construction industry due to a shortage of skilled labour can be addressed by means of system building, as quality assurance is easier to manage in a factory environment than on site. However, as the on-site assembly still needs to meet the required standards to allow the design to perform efficiently, there is still a need for some skilled labour. In the past, poor workmanship at this point in the construction process has damaged the image of system building (Glass, 1999).

Factory quality control procedures means that waste can be managed and recycled appropriately. Also, by using prefabricated components, the amount of waste generated on site can be minimised, reducing the need for such common practices as over-ordering.

Key issues in the system building method

Although most designers understand the advantages of system building, several aspects have sometimes been considered disadvantageous to its future development. Most commonly these have included inflexibility, appearance and service delivery.

Perceptions of value and aesthetics

One of the most difficult aspects of the system building method is the issue of cost. On one side there are the potential savings offered by mass production and simple assembly, but alternatively, the cost of transport, erection and attendant overheads of operating a production facility must also be borne.

Although it is relatively easy to overcome any technical problems, it is more difficult to deal with such matters as administrative, economic and aesthetic considerations (White, 1965). Of these, aesthetic judgement is considered to be the most difficult due to its often indefinable nature. The architect needs to consider the clients’ wishes and also the clients’ purse. At the same time the architect needs to consider the visual aspects of the built environment and encourage the client to do likewise. Although difficult, especially in a commercially competitive climate, the architect must nevertheless retain his professionalism with regard to visual consequences. (White, 1965).

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Fig.8 High quality typical wall units in manufacturer’s stockyard. (Glass, Jacqueline. (1999) The future for precast concrete in Low-Rise Housing. British Precast Concrete Federation, 1999).

There is a strong argument that the aesthetic value of housing does not necessarily depend on high cost, as mentioned by the Peak District Advisory Panel (1934) cited by Vale (1995, p37) “The appearance of a building does not depend primarily upon expense. Good planning, pleasant proportions and a careful choice of site and materials are far more important than cost. A capable architect can use even the cheapest materials with fine effect”.

The image of system building

The ’Kerb Appeal’ (The Popular Housing Forum, 1998) is arguably the most comprehensive research paper to investigate the determining factors involved in the purchasing of new housing in terms of appearance and layout. The ‘Kerb Appeal’ research showed that occupiers want properties that appear solid and durable. Otherwise structural form does not appear to be an issue. They also want traditional facing materials, or facing materials that look traditional, such as reconstituted stonework, which is seen as a high quality product adding value to a property.

Therefore, certain preconceived notions of how other non-traditional materials which can be used in housing need to be challenged. For example, house builders claim that the public has a low opinion of precast concrete, but there is evidence that both they and the public understand little about this material (The Traditional Housing Bureau, 1999). Raising the profile of precast concrete may be difficult, however, and may indicate a wider issue in housing. The housing industry only exists in order to sell its products and make a profit. Therefore developers will only build houses in styles and out of materials that they know both the public and the planners will approve. This conservatism, inherent in the house building industry, means that developers will only build what they think will sell and will not take aesthetic risks.

Times change, though, and recently in the UK there have been many developments - culturally, demographically, and socio-economically – and it may be that previously held attitudes towards what is considered desirable in dwellings have also changed.

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Fig.9 A precast concrete staircase as a separate component is being placed on-site.

(Glass, Jacqueline. (1999) The future for precast concrete in Low-Rise Housing. British Precast Concrete Federation, 1999).

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Fig.10 Precast hollow core panels being installed on site. (Glass, Jacqueline. (1999) The future for precast concrete in Low-Rise Housing. British Precast Concrete Federation, 1999).

Flexibility and services

Perhaps one of the most comprehensive surveys on house builders was done by Oxford Brooks University (Glass, 1999). This indicated that precast concrete was seen by some as being too inflexible a material for housing construction. The larger panels and volumetric components were criticised as being too regimented, while quality control and economic factors were also brought into question.

The provision of services may be an important factor in the discussion of the amount of flexibility offered by precast concrete. The issue centres on to what extent servicing should be integrated or incorporated into the concrete itself. Clearly there is the example of systems like Termodeck in which the structure and heating system are part of the same product, but some people argue that future flexibility of housing stock relies on servicing being more readily adaptable. However, if services are not concealed within the concrete, then these need to be accommodated in trenches, raised access floors, skirting, ducting or trunking (Glass, 1999).

When considering more highly serviced buildings, such as offices, it is usually important to conceal the electrics and lighting. In the UK there is a preference for the use of radiators instead of under-floor hot water heating systems, which might also be a factor in the choice of precast system-built products (Glass, 1999). That is to say, well- organised structure and servicing may be more important than high-tech designs with regard to precast concrete. For the occupiers, the ability to nail, drill and fix to walls and floors might be much more important than any other aspect of flexibility.

This problem can be addressed in several ways. One way would be to develop new systems for fixing, eg. those used for thin leaf dry-lined cavity walls with lightweight or foam concrete panels. Another way would be to cast a thin layer of softer material on the inside face of wall panels. Incorporating knock-out wall panels might also be needed in, for example, tenanted housing, because it is likely that occupiers will desire to make their own individual changes to the building fabric. Using precast concrete makes it possible to provide both knock-out panels and movable panels as required. (Glass, 1999)

Procurement

Japan is the most developed market in terms of precast components due to its comprehensive supply chains and innovative designs (Barlow, 2003), and therefore should be used as a model for the construction industry in the UK. Professor David Gann of Sussex University believes that UK house buyers should be offered the same level of service and choice as when buying a car (Bottom et al., 1996. In Glass, 1999).

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Fig.11 Modular precast unit being lifted to form multi-storey apartments. (Glass, Jacqueline. (1999) The future for precast concrete in Low-Rise Housing. British Precast Concrete Federation, 1999).

Being able to do this would raise the image of precast concrete from a commodity to a value-added product in the purchasers’ opinion. Also, the service delivery approach as mentioned above might be expanded to take into account the changes taking place currently in the UK housing market. As house builders, self-builders and housing associations are all potential purchasers of precast products, the UK might do well to adopt the EC approach of marketing a portfolio of complementary products (Glass, 1999). Many companies sub-contract a lot of site activities, so there are many opportunities to bring about change. Precast products could be utilised in this way, i.e. by sub-contractors. An example of this is precast flooring, which is already sold on a supply-and-fix basis. Manufacturers and house builders need to work together in order to offer all necessary services i.e. supply, fix and completion.

There are three options for precast housing (Glass, 1999):

- Design, manufacture & supply of plain components, panels, pods etc
- Design, manufacture and supply of complete integrated solutions including
services and finishes.
- Both of the above to the point of completion on site of a dry envelope

Investment is also a significant aspect of partnerships between different bodies that have very different requirements, e.g. manufacturers might need large amounts of capital investment for their factories, whereas construction companies have traditionally depended on land banks for their assets. In other words, each has its own strengths and weaknesses, and therefore each will benefit by being in partnership with the other.

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