Pre-assembly in Construction (CRISP)

Background This report was commissioned by the Technologies and Components Task Group of the Construction Research and Innovation Strategy Panel (CRISP). Its purpose is to identify, illustrate and where possible categorise recent and current initiatives on pre-assembly, particularly within UK construction. Pre-assembly literally means to ‘assemble-before’. Pre-assembly covers the manufacture and assembly (usually off-site) of buildings or parts of buildings or structures earlier than they would traditionally be constructed on site, and their subsequent installation in to their final position. Pre-assembly can be sub- divided into four categories: • Component manufacture and sub-assembly • Non-volumetric pre-assembly • Volumetric pre-assembly • Modular building Current Research Almost £5 million has been invested by DETR and EPSRC in research projects that include pre-assembly in construction since 1997. Of this total figure, around £1.1 million covers general innovation which includes pre-assembly, with the remainder concentrating more specifically on pre-assembly. Because of the gearing of the funding, the actual overall value of the research is twice the funded value (ie ~£10 million), with the extra being funded, usually in kind, by the industry partners. The main schemes that have funded pre-assembly re search in the UK construction sector include the EPSRC/DETR Innovative Manufacturing Initiative (M eeting Clients’ Needs through Standardisation) and the DETR Partners in Innovation programme. Pre-assembly has been well represented in the funding schemes over recent years although it is often disguised as part of broader research projects on innovation and frequently different terms are used instead of pre-assembly. Many projects also combine pre-assembly with standardisation (for more information on this see CRISP report 00/20). Many of the projects reviewed are still in progress and so the outcomes are not yet fully understood. This work has focussed on various different technologies and materials, often led by industry bodies with obvious priorities set by their membership. The research projects reviewed are spread across the industry sectors and involve most of the industry bodies and many universities. There may be an opportunity to check for cross fertilisation between these groups and between the findings of their respective projects. In addition to their input to government funded projects, industry is doing its own work, but the results are often commercially sensitive and confidential. In particular there has been a recent increase in developments in the residential sector. Many different university research teams are also involved, with a small number doing most of the work, however, there is little evidence of coordination between teams. This has resulted in a challenge for future work to ensure that it is organised in a holistic manner and takes best advantage of the other work that is already underway. Furthermore, the deliverables from the funded projects vary considerably, from CDs, videos, high-impact publicity documents to word-processed reports and le arned journal papers. Some deliverables have been disseminated widely and others hardly at all. Websites have been used, but their quality and accessibility again vary widely. Few of the projects have developed the deliverables to the level of practical ‘sharp-end’ guidance and advice. The existing DETR and EPSRC websites have not been kept up to date and information on deliverables have often not been added to the data. There appears to be no one place where interested parties can go to obtain information about pre-assembly research. There is a good opportunity to draw together these deliverables and make them more accessible providing the lead-researchers of the projects are co-operative. Also, future projects could be encouraged to concentrate more strongly on effective dissemination. There are also challenges to take some of the existing work and apply it in a broader sphere, or in a more co-ordinated, strategic manner. The various research networks may be a good way of achieving this, but they have not been going for long enough to evaluate their effectiveness. The deliver ables from existing projects are varied in quality and format, with some focussed on dissemination to industrial end-users and others more suitable for academic audiences. Some of the more academic deliverables may be able to be developed into tool kits or other industry-focussed output. Some international work has been related to the UK situation, but this study has not included a full international review. Motivators, facilitators, barriers and implications Motivators, facilitators, barriers and implications include: clients and the project team; procurement methods and supply chain relationships; formal/contractual requirements; legislation; changing construction to a manufacturing process; whole life costing, sustainability and waste reduction; people issues, skills and training; new materials and technologies; information and communications technology; pre-assembly; and the measurement of success. There are also some sector-specific issues. Benefits from pre-assembly are often realised else where in the construction process. Some leading repeat-order clients have started to acknowledge this and moved towards better consideration of pre- assembly, but the one-off clients are harder to involve in this movement. Advisors to the ‘one-off’ client sector appear to be significant barriers to further implementation. The principle of the important influence of procurem ent routes and supply-chain relationships for pre- assembly implementation appears to be accepted. But there are many other drivers for procurement routes and there has been much work already completed in this area. By contrast, there has been little work on the link between pre-assembly and formal or contractual requirements, nor on the effect of legislation. Successful implementation of pre-assembly depends on the industry moving towards a manufacturing process approach and away from an on-site construction approach. Whilst this has been acknowledged, it does not seem to have been worked out in the projects completed to date. Whole-life costing studies have not been completed for pre-assembly and, although they have been raised, issues of sustainability in pre-assembly have not really been resolved. People issues have not been covered in much of the existing work except for a project on health and safety and one on skills, education & training. Further opportunities in these areas could be established once these projects have delivered. There is little evidence of the study of new materials for pre-assembly, although this subject is covered in more detail in another CRISP report recently commissioned. Because of the way that much of the pre-assembly supply chain is organised, the current applications for ICT are somewhat limited. This should be an area of further opportunity, but only if the supply chain moves to embrace ICT more fully. Existing methods of measuring project success are not developed sufficiently to adequately evaluate the benefits of pre-assembly, but a number of existing projects are currently working in this area. The research on pre-assembly is more or less evenly split between general (no specific sector) (36%), the residential sector (39%), and the remainder major building and civil engineering with a small amount covering maintenance, repair and refurbishment. There appears to be little work aiming to co-ordinate this work or apply lessons learnt in one sector to the challenges of another sector. Conclusions There is much existing research work looking at pre-assembly, although it is often combined with broader subjects. Much of the work is not co-ordinated well and benefits may be gained from further efforts in this area. Further work should be encouraged especially where it effectively engages the whole supply chain and is targeted on producing end-user guidance

Standardization and pre-assembly- distinguishing myth from reality using case study research

Standardization and pre-assembly (S&P) are not new, but their application and their drivers, pragmatism and perception, need to be considered in the light of current technology and management practice. There are lessons to be learned from a historical review, but there are also numerous myths that must be dispelled: houses are not cars; maximum standardization is not always the answer; and, S&P do not have to cost more. Steven Groák worked with the author on the research project ‘Adding value to construction projects through standardisation and pre-assembly’ funded by CIRIA (Construction Industry Research and Information Association). The CIRIA project, which forms the basis of this paper, aimed to produce a review of the subject and guidance for clients and project teams through a comprehensive literature review, expert work5 shops and case study research. The paper defines S&P, discusses past, present and future applications (providing case study evidence) and presents the key benefits and implications of the optimized use of standardization and pre-assembly

Standardisation in Construction (CRISP)

Background This report was commissioned by the Technologies and Components Task Group of the Construction Research and Innovation Strategy Panel (CRISP). Its purpose is to identify, illustrate and where possible categorise recent and current initiatives on standardisation and customisation, particularly within UK construction. Standardisation is the extensive use of processes or procedures, products or components, in which there is regularity, repetition and a record of successful practice. Customisation is the process of using standard components or sub-assemblies to produce a variety of end products to suit the needs of the end-user. Technical standards (e.g. ISO) are not included in this review. Current Research Between 1997 and 2000, almost £6.7 million has been invested by DETR and EPSRC in research projects that include standardisation and customisation in construction. Of this total figure, around £1.1 million covers general innovation which includes standardisation, with the remainder concentrating more specifically on standardisation. The main schemes that have funded standardisation research in the UK construction sector include the EPSRC/DETR Innovative Manufacturing Initiative (Meeting Clients’ Needs through Standardisation) and the DETR Partners in Innovation programme. There is much work that claims to cover standardisat ion, often combined in some way with pre-assembly or general innovation. Pre-assembly research is covered in a separate report for CRISP (00/19). Many of the projects are still underway and so a full review was not possible. The appendices include summaries of the research projects, patent records and professional journal articles reviewed. The research projects reviewed are spread across t he industry sectors and involve most of the industry bodies and many universities although the main players are Salford, Loughborough and Warwick Universities and the Building Research Establishment. There appears to be little direct collaboration between projects. In some ways this is to be expected as the subject itself is very diverse. Nevertheless, further benefits should be possible by seeking to draw together the results from the various projects and to encourage the different parties to collaborate on future projects. The deliverables from existing projects are varied in quality and format, with some focussed on dissemination to industrial end-users and others more suitable for academic audiences. Some of the more academic deliverables may be able to be developed into tool kits or other industry-focussed output. Further benefits for dissemination are possible th rough the EPSRC’s industrial secondment scheme. Some international work has been related to the UK situation, but this study has not included a full international review. Motivators, facilitators, barriers and implications Motivators, facilitators, barriers and implications include: clients and the project team; procurement methods and supply chain relationships; formal/contractual requirements; legislation; moving construction towards a manufacturing process; whole life costing, sustainability and waste reduction; people issues, skills and training; new materials and technologies; information and communications technology; pre- assembly; and the measurement of success. There are also some sector-specific issues. Leading repeat-order clients are at the forefront of research and implementat ion of standardisation, convinced that significant savings can be made. The benefits are not so obvious to one-off clients and this offers a real challenge for the future although some work is just about to start in this area. There are competing drivers within project teams, with those involved in long-term strategic relationships better able to realise the benefits. This is also true for a ll parties in the supply-chain where the effect of standardisation may be relatively insignificant when considered company by company, but adds considerable value when employed within an overall supply-chain strategy. However, the cultural barriers to standardisation should not be underestimated, especially within the design professions. The most significant challenges are to combine top quality design with the principles of customised standardisation and to change the construction process into a manufacturing process without returning to the mass production of the 1950s and ‘60s.. The principles have been identified but they are not yet employed consistently. Standardisation has generally led to reduced cost and improved quality, but occasionally there have been examples where the specification of a standard product has not produced these expected outcomes. The whole supply chain needs to be engaged in research to prevent this from recurring. As the supply chain develops, then better deployment of some of the standardised ICT applications and data handling methods will be required. This may occur in any case and at considerable speed, driven by commercial pressures and may not require specific research input. Whilst there has been research on standard processes and changing the construction process to a manufacturing process, there is little direct investigat ion into the effect of standardisation on formal or contractual requirements or their effect on standar disation. The same is true for legislation. Whole life costing and sustainability have been much talked about, but there is little direct research on the causal relationship with standardisation. The availability of spare parts for example is a clear driver, but there appear to have been no rigorous studies to eval uate whether such expected benefits are achieved in practice. There is significant opportunity for human factors work on standardisation, both in evaluating the effect on construction workers, end-users and the general public. The link between standardisation and innovation has been identified in principle, but more development of strategies to ensure that standardisation does not act ually act as a barrier to product improvement or innovation could be beneficial. Benefits from standardisation have been identified in much of the previous and existing work, but accurate measurement of these benefits remains elusive. Working on this further with leading repeat order clients may be possible, but overcoming the desire for headline statistics may prove difficult. Conclusions There is much existing research work looking at standardisation, although it is often combined with broader subjects. Furthermore, the subject is very broad and as a result projects are diverse and hard to draw together as one body of knowledge. Much of the work is not coordinated well and benefits may be gained from further efforts in this area. Further work should be encouraged especially where it effectively engages the whole supply chain and is targeted on producing end-user guidance

Barriers and opportunities for offsite in the UK

The UK still falls behind most equivalent economies in terms of the takeup of industrialisation in construction and techniques such as offsite construction. Interest in the UK in industrialisation and offsite has recently been increasing however, partly attributable to the increased demand for housing, and pressure by Government and industry to improve the performance of the UK construction industry, particularly its efficiency, quality, value and safety. This paper discusses the views of the UK construction industry on offsite. This work has been conducted by Loughborough University as part of a DTI and UK industry funded research programme on offsite technologies and prefabrication called prOSPa (promoting OffSite Production applications). This paper presents results from a recently completed questionnaire survey on offsite and prefabrication in the UK. A preliminary survey was used to guide and inform the development of a main survey involving three different questionnaires in order to target the three main groups of stakeholders involved with offsite suppliers/manufacturers, contractors and designers/clients. More than 90% of the respondents had used some type of offsite or prefabrication in at least one of their projects. Demand for offsite is clearly increasing in the UK and nearly three quarters of the suppliers surveyed thought that take-up of offsite by industry was increasing in their sector. The biggest advantages of offsite compared with traditional construction were thought to be the decreased construction time on site and increased quality. The belief that using offsite is more expensive is clearly the main barrier to its increased use

Maintenance performance evaluation of offsite and in situ bathrooms

Purpose – Offsite is one of the main innovative techniques employed in the contemporary UK construction sector. Building maintenance accounts for over 5 percent of the UK's gross domestic product of which bathrooms are regarded as a critical area, with potential high risks and defects. However, the importance of its maintenance has been largely underestimated and research into this area appears to be limited. This paper aims to address this knowledge gap by investigating the maintenance performance of offsite and in situ bathrooms for student accommodation. Design/methodology/approach – The paper examines 732 maintenance records over three years of 216 precast concrete modules, 84 Glass Reinforced Polyester (GRP) modules and 96 traditionally-built in situ bathrooms. Findings – The research found that offsite modules outperformed in situ bathrooms in terms of maintenance. GRP modules created the least maintenance problems, compared to precast modules and in situ bathrooms. The maintenance of in situ bathrooms was more complex than offsite modules, and involved more diverse problematic areas. The main causes of the problems included inappropriate design; poor build workmanship, lack of quality of component materials and improper usage by occupants. This supports a parallel study that found that the costs associated with maintenance were significantly higher for in situ bathrooms than for the equivalent offsite solutions. Research limitations/implications – The paper contributes to understanding the problems of offsite bathroom modules requiring maintenance in comparison with in situ bathrooms and their possible causes. Key aspects of offsite bathrooms including drainage, toilets, vents and sinks should be improved. Quality of component materials used for in situ bathrooms should be ensured. These improvements can only be achieved through better design for maintenance with clients' aspiration embodied. The findings should assist in design decision making of selecting bathrooms for residential buildings. However, a balanced approach, taking into account other factors for such selection, is open for future investigation. Originality/value – The framework of strategies developed should improve the innovative design of bathrooms manufactured offsite and help maintain them for better lifecycle performance

Future opportunities for offsite in the UK

Practitioners views and opinions on the benefits and drawbacks of offsite technologies in the UK construction industry can vary widely, often depending upon their role or position. This research provides an indication of the opinions of the different sectors within the industry, including clients, designers, contractors, and offsite suppliers, together with some predictions for the future growth of the offsite sector in the UK. A questionnaire survey of UK construction was conducted in order to target the three main construction industry sectors - suppliers/manufacturers, contractors and designers/clients. More than 80 questionnaires were completed and returned. The vast majority of practitioners within the industry are aware of the possibilities and potential of offsite, and most also understand the advantages and disadvantages of its use. The value of the UK offsite market was valued at £2.2bn in 2004 and the demand for offsite is clearly increasing, but it is not always clear in a project who is the main driver for its use. For the offsite market to develop further however, two main problems need to be addressed; the lack of transparent information for the decision makers in the construction process, particularly that relating to comparative costs, and the lack of available multi-skilled labour to work in the offsite factories

Nanotechnology: exciting facilitator or worrying innovation?

Nanotechnology is an important feature of concrete technology and innovation in the 21st century. Nanoparticles are enabling concrete technologists to make significant steps forward in terms of concrete performance. However, there is some evidence suggesting health concerns from nanoparticles. Much of this has focussed on the manufacturing processes but there remains a potential health risk for construction in the bioavailability of nanoparticles through working of the products during installation, maintenance and in particular demolition. This paper introduces some new research funded by IOSH to investigate this issue

New build: materials, techniques, skills and innovation

The transition to secure, sustainable, low-energy systems will have a significant effect on the way in which we design and construct new buildings. In turn, the new buildings that are constructed will play a critical role in delivering the better performance that would be expected from such a transition. Buildings account for about half of UK carbon dioxide (CO2) production. So it is urgent to ensure that energy is used efficiently in existing buildings and that new building stock is better able to cope with whatever the future holds. Most energy used in buildings goes towards heating, lighting and cooling, but a growing percentage is consumed by domestic appliances, computers and other electrical equipment. Actual energy consumption is the product of a number of factors, including individual behaviours and expectations, the energy efficiency of appliances and the building envelope. This review focuses on the third of these, the building itself, and its design and construction. It discusses the issues faced by the construction industry today, suggesting that major changes are needed relating to materials, techniques, skills and innovation. It moves on to consider future advances to 2050 and beyond, including developments in ICT, novel materials, skills and automation, servitisation (the trend for manufacturers to offer lifetime services rather than simple products), performance measurement and reporting, and resilience. We present a vision of the new build construction industry in 2050 and recommendations for policy makers, industry organisations and construction companies

Manual handling of highway kerbs—focus group findings

The manual handling of concrete highway kerbs remains commonplace in the construction industry despite obvious risks to operatives. A study was commissioned to find out why the operation still includes manual handling, what alternatives exist and how the organisation of the work affects exposure to risk. Although this study involved a literature review and visits to examine manufacture, supply and installation of kerbs, the focus groups which were held with industry professionals to discuss manufacture, installation methods, design and training are reported here. Related published research was very limited and the visits confirmed manual handling to be widespread for installation but eliminated or controlled in other areas of the process. Risks to health of construction workers remained as they were not considered in the design of the product, design of the work or identified and controlled through risk assessments. Focus group findings highlighted manufacturer’s myopia, lack of installation knowledge of designers and shortfalls in training of installation work. Recommendations from the research are that a pro-active approach to health needs to be adopted by the manufacturers of heavy construction products. Designers of work 2 requiring the use of heavy products need to have more experience of site operations, and training of manual handling awareness should be performed at all levels in construction organisations

Establishing and weighting decision criteria for building system selection in housing construction

A lack of value-based decision criteria leads to an inability to effectively compare prefabrication and off-site production with conventional construction, which inhibits the realization of benefits of off-site approaches. This paper develops value-based decision criteria and quantifies their relative importance for assessing building technologies systematically. The research employed a multimethodological strategy within a broad case-study-based design, with six large house-building organizations in the United Kingdom. These companies together accounted for more than one-tenth of new-build home completions in the United Kingdom. More than 50 criteria were developed, grouped under cost, time, quality, health and safety, sustainability, process, procurement, and regulatory and statutory acceptance. Cost was ranked most important, which, coupled with time and quality, predominated technology selection in these companies. Sustainability, process, and procurement were weighted lower, whereas health and safety and regulatory and statutory acceptance were deemed compulsory, hence offering no trade-off opportunity. A lack of incorporating innovative sustainable technology into corporate strategy was observed. The developed criteria and the systematic process should help house-building organizations manage technological innovation and hopefully achieve more informed corporate decisions