Off-site Manufacturing Research Articles

Barriers to Offsite Construction Adoption: A Quantitative Study among Housing Associations in England

Housing associations (HAs) play a pivotal role in the delivery of affordable homes and, therefore, offsite construction could be beneficial in alleviating the crisis. Existing literature has focused on the perceptions of the housing sector at large towards offsite construction (OSC), particularly private housebuilders. This research addresses this gap in the literature. This paper explores the perceived barriers of using OSC through a survey of the largest HAs in England [n = 69], and how these compare with the perceptions within the wider housing sector. The evidence from this research indicates cost-related barriers are perceived to be the most significant barriers to OSC use for HAs, followed by the capacity of suppliers and end-user preferences for traditional construction. The perceived barriers of those with experience are aligned with the OSC literature, whilst the responses of those without direct experience suggested heightened concerns towards the key barriers. A conceptualised feedback model is proposed to monitor, capture knowledge and share best practice as HAs commit to accelerating project delivery through strategic partnerships with offsite manufacturing firms, local authorities at a local/regional level, that leverage the high-value, high-impact transformation of the housebuilding sector in tangible terms of efficiency, cost, and material savings.

Prefabricated Building Systems—Design and Construction

Modern Methods of Construction with Offsite Manufacturing is an advancement from prefabricated technologies that existed for decades in the construction industry, and is a platform to integrate various disciplines into providing a more holistic solution. Due to the rapid speed of construction, reduced requirement of labour and minimised work on site, offsite manufacturing and prefabricated building systems are becoming more popular, and perhaps a necessity for the future of the global construction industry. The approach to the design and construction of prefab building systems demands a thorough understanding of their unique characteristics.

How countries achieve greater use of offsite manufacturing to build new housing: Identifying typologies through institutional theory

The need to address housing supply deficits has driven global efforts to transform the construction industry, and in particular, to achieve greater use of offsite manufacturing (OSM). Countries like Japan, Germany and Sweden have been more successful than others in driving greater use of OSM to build new housing. How these countries achieved such success, and lessons for how others may reach such levels of using OSM to build new housing, are yet to be identified. To address this gap, in this paper we applied institutional theory to analyse the factors driving greater use of OSM to build new housing in seven selected countries. Qualitative content analysis of 95 documents enabled the identification of four typologies that have led countries to the greater use of OSM for new build housing. The four different typologies, characterised by various coercive, normative and mimetic institutional pressures, show that there is no one single strategy for guaranteeing success. An individual country cannot directly transfer specific aspects of policy and practice used in another country to their own in order to drive greater use of OSM for building new housing. Our findings also underscore the need for the further application of institutional theory to OSM research in order to better understand how history and path dependence, for instance, shape the trajectory of gradual shifts from onsite construction to the greater use of OSM to build housing in different countries.

Process Waste Analysis for Offsite Production Methods for House Construction: A Case Study of Factory Wall Panel Production

AbstractThere is growing interest in the use of offsite manufacturing (OSM) in the construction industry despite criticism that some offsite approaches used by housebuilders do not offer real impro...

Applications, performance, challenges and current progress of 3D concrete printing technologies as the future of sustainable construction – A state of the art review

The construction industry is moving closer to 3D printing in concrete for the manufacture of architectural or building components. Construction Industry is expected to drastically modify current processing methods and perhaps lead to disruptive technologies for instance 3D concrete printing (3DCP), resulting in significant variations in the construction industry. Around the world, the construction industry and research initiatives are concentrating on automated construction technologies. There have been several technologies for 3DCP of concrete elements developed, and their use in building projects is increasing. 3DP's growth isn't confined to Earth; it's also gaining traction as a means of constructing space habitats. 3DCP allows for freeform building without the need for costly formwork, which has several advantages over the traditional method of pouring concrete into a formwork. In recent years, several 3DCP technologies have been created. Techniques and procedures that have been tested include on-site and off-site manufacturing of building components employing industrial robots, gantry systems, and tethered autonomous vehicles. This article presents the current state-of-the-art in the subject of 3D printing of buildings and construction components. The purpose of this research is to describe the technical, socioeconomic, and environmental components of 3DCP of concrete structures in order to provide a comprehensive overview of the 3DCP technology, applications, challenges, and future research and market opportunities in the construction sector. This research focuses mostly on current breakthroughs in 3D concrete printing, as well as other research and development projects in this subject, notably its use in alien habitats. There are several advantages to using this strategy, including cost and time savings, decreased pollutants, and a reduction in accidents and fatalities on construction sites. Despite the various benefits and prospects, the results raise certain concerns, owing to the technology's existing limitations. According to this comprehensive review, researchers should examine the challenges such as on-site fabrication, large scale manufacturing process and limitations of 3D concrete printing further in order to increase mechanical performance, durability, and sustainability, as well as create appropriate standard criteria for printing structures.

Assessing the Off-Site Manufacturing Workers’ Influence on Safety Performance: A Bayesian Network Approach

AbstractOff-site manufacturing (OSM) offers a wide range of benefits to the construction industry by saving time, reducing waste, being an environmentally friendly solution, and providing a much sa...

Modular Robotic Prefabrication of Discrete Aggregations Driven by BIM and Computational Design

Discrete architecture is recognized as a computational design approach which uses computation to generate algorithmically combinable aggregations. It is therefore a promising innovation for increasing design process productivity through the adaptability of the aggregations it generates. In the built environment, discrete design is usually identified with the modular method. It is a construction process based on the aggregation of different modules assembled according to well-defined connections to ensure the building’s integrity and functionality. It involves off-site manufacturing, and hence a controlled environment ensuring more predictability over weathering and change. But like in conventional construction practices, the fragmentation of modular construction processes hinders its productivity. As a result, this construction approach requires adequate technologies and communication tools to improve collaboration and productivity. This paper aims to address these requirements by adopting a BIM-driven computational approach to design processes and a robotic approach to prefabrication processes. It proposes a modular construction framework for design and production, and presents the results through a study adopting BIM-driven discrete design and robotic manufacturing.

Offsite Manufacturing Research: A Systematic Review of Methodologies Used

Debates regarding research methodologies in construction, engineering and management (CEM) literature are long-standing. However, in the growing literature on offsite manufacturing (OSM), such debates are lacking and some studies conflate different components of research methodologies such as research design, methods, data sources, data types, and analytical techniques. This study examines the components of research methodologies reported in the OSM literature and how they compare with the established relationships between the key components of research methodologies. We analyse 74 articles on OSM sampled from 26 journals and find that quantitative methods, case studies, primary data, bibliometric database and modelling are the most preferred methodological approaches. The methodological components reported also cohere with established relationships between components of research methodology, other than the relationship between research methods and data sources. The findings reveal a growing hybridisation of research designs, data sources and analytical techniques, which suggests that methodological plurality is emerging in the OSM literature. This re-echoes concerns regarding the dominance of quantitative methods and the limited use of theory in CEM research, and consequently highlights the need for diversity in methodologies to expand knowledge boundaries.

Systematic review on the identification of safety risks in off-site manufacturing (OSM)

PurposeOff-site manufacturing (OSM) has emerged as a method of modern construction that provides several benefits including achieving lower costs, a quicker schedule and environmentally friendly solutions. Although numerous researches are available that advocate the adoption of OSM, the devotion towards OSM safety is somewhat limited. However, OSM invariably generates safety risks, including dynamics and uncertainty in safety management. There is a unique call to have an investigation on the identification of OSM safety risks.Design/methodology/approachTo provide a full picture on the OSM safety, a systematic literature review was adopted based on interpretivist philosophical stance. The literature search was conducted in key electronic databases to identify OSM safety-focused publications. Bibliometric analysis was adopted to identify co-occurrences of keywords and collaboration among authors in OSM safety-related research publications. Content analysis was conducted to provide a taxonomy of OSM safety risks. The identified studies were critically analysed to determine the focus of OSM safety research and provide future research directions.FindingsThe results demonstrated frequently appeared OSM safety aspects while highlighting the limitedness of collaborative research outputs in common authorships. Content analysis subsequently unveiled safety risks in OSM under human, organisational and work environmental factors. A critical analysis of extant literature revealed seven research classifications of OSM safety. Directions were offered to enhance OSM safety by applying principles of targeted safety management concepts, technology-driven safety measures and bespoke training programs.Originality/valueThis study provides a comprehensive review on the identification of safety risks throughout OSM while presenting the avenues useful for the development of OSM safety management strategies.

Trent Brick Panel: innovative envelope system designed according latest UK national fire and energy performance regulations

In November 2018, following the Grenfell Tower tragedy in London, the Ministry of Housing, Communities & Local Government (MHCLG) introduced an amendment to the Building Regulations 2010, which outlined stricter rules banning the use of combustible materials defined by the new Building Regulation 7(2). This change had a significant impact since early 2019, on the materials and systems that can be used in the construction sector. In 2020, the global pandemic caused by the diffusion of the COVID-19 virus represented a new challenge for the industry, with implications on programme certainty, material procurement, workforce management, moving towards offsite manufacture. The development of the Trent Brick Panel is set against this historical and social context. The envelope prototype is the opportunity for innovation that follows the turn of events. The offsite manufacturing of glass-reinforced concrete panel, mimicking several finishes, is the result of a design investigation carried out with the market-leading actors: developers, main contractors, subcontractors, engineering consultancies, architects, local authorities and warranty providers. The research aims to give an overview of the design principles, sequence and buildability study, assessed weathering performance according to CWCT Sequence B test and fire performance.

The social acceptance of mass produced residential buildings among Hungarian young adults

ABSTRACT Off-site manufacturing may play a significant role in improving both process and output productivity in the construction industry and achieving UN Sustainability Development Goals 11 and 13. However, uniform mass production can lead to a monotonous built environment that may be alienating to people. Past examples show that such buildings and neighbourhoods can rapidly become obsolete, which makes them unsustainable. In this study, two online surveys were conducted with over 100 participants focusing on prejudices towards mass manufactured residential buildings and diversity requirements for homes among Hungarian young adults. In contrast to previous studies, respondents evaluated example scenarios with standardised buildings not as observers but by imagining how they would feel or act in situations involving these buildings. The first survey examined the bias of respondents towards mass manufactured buildings with Likert, Thurstone, and semantic differential scales. The second examined how respondents would feel if they visited a home similar to their own by varying visiting frequency and degree of similarity. T-tests showed that prejudices were positive, except concerning mass manufactured buildings’ diversity, and respondents were only negative about having to see identical dwellings to theirs on a regular basis. The results suggest that in Hungary, non-uniform but standardised residential buildings can serve as a suitable tool to provide affordable housing to young adults affected by the housing crisis.

Information traceability platforms for asset data lifecycle: blockchain-based technologies

PurposeThe emergence of new digital technologies in the era of the Fourth Industrial Revolution presents a turning point that could change the fate of the traditional ways of designing, build and manage asset data. Disruptive technologies such as Blockchain and theInternet of things (IoT) are one of the main pillars that are driving this revolution. The integration of decentralised networks and automated workflows has the potential to become a pivotal factor in construction projects, especially in supply chain ecosystems within the off-site manufacturing field. Obstacles related to fragmented information, interoperability, transparency and “big data” management are the main drivers for change that the industry needs to address. Whilst organisations and users can automate workflows and processes by utilising IoT technology to transfer data without human-to-human or human-to-computer interaction, the interaction, storage and management of the data generated are not safe or reliable.Design/methodology/approachThe approach outlined in this paper addresses the challenges that IoT and centralised networks present. Blockchain, a peer-to-peer distributed database, offers the possibility to support and maintain the asset information without interruptions in all the stages of the life cycle. The synergy between these technologies, along with other techniques, methods and platforms (such as building information modeling (BIM)), based on a single environment, will support information traceability from the strategic definition to end of life.FindingsThe framework of this study presents an excellent opportunity to apply new workflows and processes with the application of new technologies and protocols. It benefits from a well-established platform such as BIM to enable the coordination and management of digital assets as well as giving illustration and collaboration to the supply chain members. IoT and Blockchain are the other layers that work together with the third layer (BIM). This framework proposed the use of these platforms to ensure the information traceability of physical and digital assets, data automation and information management, in a dynamic supply chain ecosystem, bringing efficiency and transparency to stakeholders and users.Practical implicationsThis study provides an exploratory framework to be used by the supply chain members in offsite manufacturing, and the architecture, engineering and construction (AEC) industry in general, to track asset information throughout their entire life cycle securely and transparently.Originality/valueThis paper contributes to the knowledge of IoT, Blockchain technology and BIM use in offsite manufacturing under the AEC industry. It provides a basis for future research by professionals, experts and academics regarding these technologies and their workflows.

Flexural behaviour of improved joint details connecting pre-cast bridge decks

The joints between pre-cast concrete slabs contribute to the construction of continuously reinforced concrete slabs using pre-cast elements, thus considerably reducing the overall construction time and improving the construction quality of off-site manufacturing. A series of bending tests were conducted on specimens with six joint details. The six joint details included the lapped U-bars (LU), lapped U-bars with stainless-steel ties (LUS), lapped U-bars with T-shaped joints (LUT), lapped headed bars (LH), welded linear bars (WL), and lapped linear bars (LL), where LUS and LUT were proposed by this study. In order to compare the mechanical properties of U-bar, headed bar and linear bar joint, the six specimens were evaluated according to the bearing capacity, failure types, crack control, rigidity, and steel strain. The specimens with LUT had the highest bearing capacity (204.7 kN⋅m) that was 4.8 %, 8.9 %, 25.7 %, 45.2 %, and 42.7 % higher than the capacities of the LU (195.4 kN⋅m), LUS (188 kN⋅m), LH (162.8 kN⋅m), WL (141 kN⋅m), and LL (143.4 kN⋅m) specimens, respectively. The specimens with the U-bars had higher bearing capacity and displayed ductile failure whereas the specimens with the headed and linear bars had lower capacity and underwent brittle failure. Based on the experimental results, the LUT detail proved suitable for fabricating joints between pre-cast concrete slabs. The test results were compared with the calculation formula and the published tests. The specimens in this study represent an improvement upon the large-size, high-bearing-capacity specimens in the joint study.

Exploring Servitization in Industrial Construction: A Sustainable Approach

Off-site manufacturing is emerging as an advantageous production model in the construction industry. In recent years, many tier 1 construction companies are including off-site production as part of their portfolio. Likewise, this change of model is attracting new entrants to the sector. The shift from the traditional on-site construction model to off-site manufacturing is unleashing positive impacts on projects in terms of cost, time efficiency, sustainability, and improved quality. Nonetheless, this phenomenon has yet to be analysed from the perspective of how this change in production processes influences the inclusion of services in company business models. This study explores whether and how industrialisation arises as an enabler for servitization in the construction sector. By means of an in-depth case study, our research identifies different product-service system (PSS) typologies associated with industrial construction and reveals their potential to increase additional services. Furthermore, the research sheds light on how industrial construction provides an opportunity to integrate offers and features that work towards reducing the environmental impact of construction projects and the operation and maintenance of built assets.

An Exploration of the Best Value Perceptions of Small Housebuilding Developers towards Offsite Construction

Offsite construction is increasingly being presented as a way to increase housing delivery and reduce the housing crisis. Large developers play a pivotal role in the delivery of affordable homes and therefore offsite construction could be beneficial in alleviating the crisis. Previous Offsite Construction (OC) studies conducted into the drivers, barriers and decision factors provide qualitative analysis from manufacturers and larger developers appear to be taking advantage of the UK government’s renewed interest in offsite manufacturing and have begun investing in these methods. However, the role of smaller housebuilding developers in the use of offsite construction systems is rather more uncertain. This research addresses this gap in the literature through an exploration of small housebuilding developers’ best value perceptions of offsite construction methods within the UK housebuilding sector. A questionnaire survey was used to ascertain perceptions of the 134 small developers towards the drivers, barriers and decision factors identified in the extant OC literature. Although survey respondents had not widely used offsite manufactured systems previously, the results indicate a high level of agreement with the drivers identified within the offsite construction literature. The respondents identified the buyers’ perception of traditional methods as superior to OC systems and creating higher sales figures. Many any of the respondents also believe that best value, and hence maximised profit, higher sales value, and greater returns on investment, is achieved through traditional methods of construction. These two factors combined are more desirable for small developers, rather than the perceived increase in sustainability and efficiency offered by OC systems, due to their positive effect on profit.

Deploying 3D scanning based geometric digital twins during fabrication and assembly in offsite manufacturing

Verifying geometric compliance in offsite manufacturing (OSM) is key for ensuring adequate fit-up, structural integrity, building system performance, and assembly alignment on site. The use of a geometric digital twin (gDT) from 3 D scanning can be used to digitize an assembly to detect and resolve potential problems in a prescient manner. The contribution of this article is the development of a framework for deploying and comparing three distinct gDT approaches for use during fabrication and assembly in OSM: (1) a scan-vs-BIM approach, (2) a scan-to-BIM approach and (3) a parametric BIM updating approach. Results from a commercial building project show that scan-vs-BIM is the most accurate approach, parametric BIM updating produces the most semantically rich gDT, and scan-to-BIM is a middle-tiered option, striking a balance between representational accuracy and semantic enrichment. This study concludes that future research should develop a hybrid solution of these gDT approaches and additional more accurate measurement technologies for optimal deployment in OSM.

Design, manufacture and construct procurement model for volumetric offsite manufacturing in the UK housing sector

PurposeThe purpose of this study is to gain insight into procurement routes and forms of contract used for volumetric offsite manufacturing (VOSM) in the housing sector of the UK West Midlands. Seminal literature and government reports have established the potential of offsite technologies to improve the supply of quality housing in the UK. However, the lack of a structured procurement route, common to manufacturing approaches in construction, has significantly contributed to delays in large scale adoption.Design/methodology/approachTo achieve the research intention, an exploratory study was undertaken. A literature review of seminal literature and government papers was conducted to establish and benchmark current trends in context. Data was collected using focus groups and interviews with a housing association and housing VOSMs. Grounded theory was used to analyse data and inductively generate themes leading to an original procurement model. The issues identified in the delivery of volumetric housing were categorised into three themes.FindingsThe findings suggest a limited familiarity with offsite manufacturing (OSM) by housing providers. Albeit, a willingness to adopt these technologies to deliver housing were demonstrated by trial attempts. However, due to limited knowledge, the approach to procurement is by adapting existing procurement models, which are not ideal and obstruct the potential benefits of using offsite technologies primarily because of the significant difference in processes. Also, geographical location influenced procurement decisions when comparing cost with conventional procurement and the dearth of specific government incentives to deliver housing using offsite technologies. This study proposes a procurement model for VOSM.Practical implicationsThe results have implications for decisions about procurement routes and contractual terms used by housing providers delivering volumetric offsite manufactured housing at scale. Although this study focussed on the West Midlands region, most of the issues identified were not geographically unique.Originality/valueThis study contributes to the existing body of knowledge on potential barriers to the adoption of OSM in the housing sector of the UK. The findings will be of value to stakeholders involved in delivering housing and offers a useful contextual basis for future research.

Actor-network theory and the evolution of complex adaptive supply networks

PurposeCurrent understandings of innovation in construction portray it as linear, deterministic phenomena centered around novel objects and technologies deployed in sequentially-organized supply chains. This study aims to develop an enriched understanding of construction innovation as non-linear, socio-material and dynamic phenomena in complex networks by formulating a novel conceptual apparatus of complex adaptive supply networks (CASNs) expanded through actor-network theory (ANT) concepts.Design/methodology/approachThis combined CASN/ANT apparatus is mobilized in the context of a qualitative case study involving a housing construction supply network in Australia making use of offsite manufacturing (OSM) techniques.FindingsThe study shows that innovative technologies such as novel OSM products can play an important though not necessarily deterministic role in the evolution of CASNs. The study also explicates the process by which the enrollment of non-human agents and the resulting CASN evolution are linked: innovative technologies shape human and non-human interactions in ways that redefine task delegation, role definition and schemas that are fundamental to the shape of CASNs.Originality/valueFindings provide a compelling empirical basis for arguing that CASNs must be conceptualized as heterogeneous systems and that innovation in construction must be understood as non-linear, socio-material and dynamic, rather than linear and driven by technological determinism. The study also interrogates limiting notions of supply chains and supports the notion of alternative inter-organizational forms to understand construction project work.

A new paradigm in a low-rise housing construction

The article highlights the structure of consumer demand in the individual real estate market. Construction technologies based on "prefab housing" (construction of houses from prefabricated factory structures) are described. The transition from on-site manufacturing technologies (erection of houses directly at construction sites) to modern construction methods ("off-site manufacturing" house building) is described.

Development and seismic retrofit of an innovative modular steel structure connection using symmetrical self-centering haunch braces

As an efficient and environment-friendly technique that combines off-site manufacturing of modules and on-site assembly, modular buildings have been adopted in many areas of the construction industry. This paper proposes an innovative modular steel structure (MSS) connection with bolted cover plates, which inserts a cross-shaped plug-in connector inside the adjacent columns to achieve accurate positioning in the module installation and provide partial shear capacity. A seismic retrofit method using hinged diagonal self-centering (SC) haunch braces is proposed for the MSS connection to improve the seismic performance and achieve functional recoverability after earthquakes. Hysteretic behaviors of the MSS connection and the self-centering MSS (SC-MSS) connection are investigated due to cyclic loadings. Results demonstrate that compared with the MSS connection, the SC-MSS connection is expected to improves strength and stiffness and exhibits stable flag-shaped hysteretic responses with a satisfactory self-centering capability. The hinged diagonal SC haunch braces are capable of reducing the average stress level around the connection core region, controlling the development of plastic damage, avoiding the local failure, and improving the ductility of connection. The present study provides practical connections and important guidance for the applications of modular steel structures in the medium- and high-intensity seismic regions.