ScienceDirect
Procedia Engineering 00 (2017) 000–000www.elsevier.com/locate/procedia
1877-7058 © 2017 The Authors. Published by Elsevier Ltd.
Peer-review under responsibility of the scientific committee of the Creative Construction Conference 2017.
Creative Construction Conference 2017, CCC 2017, 19-22 June 2017, Primosten, Croatia
The Interface between industrialized and project based construction
Niclas Andersson
aPh.D., Jerker Lessing
bPh.D.
*aFaculty of Technology and Society, Malmö University, S 205 06 Malmö, Sweden bDepartment of Building and Environmental Engineering, Lund University. S 221 00 Lund, Sweden
Abstract
Today, digitalization is the single most significant change factor for the construction sector as well as for society in general, which will bring new opportunities for intelligent and sustainable cities, efficient management of available resources and a general reduction of carbon emissions. Digitalization will enable continuous and integrated information exchange between all actors of the construction process. The development of an integrated digital information infrastructure for the construction sector will reach beyond the traditional project process and e.g. include the urban planning processes, where geographical information systems (GIS) are currently used, and the manufacturing processes of industrialized construction where e.g. product data management (PDM) systems constitute the product information platform. This study provides a survey of the interface between industrialized and project based construction from an information and business relation perspective. The purpose and main objectives of the study are to review and map the current information exchange between industrialized and project based construction in order to identify existing and potential areas of digitalization and standardization for improved information flow. The survey finds that industrial suppliers still frequently use company specific product standards, that PDF-, Word- or Excel-files constitute the normally used file format and that recurrent restructuring and re-entering of information from one system to another characterize the information exchange. Further, contractors approach industrialized construction in three distinctive ways, and express a generally growing interest for industrialized construction, which include closer and more long-term business relations with industrial suppliers. Despite the identified problems of information exchange and lack of common standards, the survey concludes that improved business relations provides the most urgent area of development in order to better integrate the industrialized and project based construction.
© 2017 The Authors. Published by Elsevier Ltd.
Peer-review under responsibility of the scientific committee of the Creative Construction Conference 2017.
Keywords: Industrialized construction; building system; information infrastructure; building standards; classification systems; business relations
* Niclas Andersson. Tel.: +46(0)703 949428 niclas.andersson@mah.se
1. Introduction
“Construction management is a problem of information - or rather lack of information” [1]. The building process is characterized by fragmentation, e.g. by its division into separated phases, a large number of highly specialized actors and a production process organized in temporary projects with new constellations of actors in every new project. The fragmented characteristics of construction provides a challenge for efficient coordination of processes, it impedes learning from experience, hinders continuous improvement by repetition and, requires significant coordination, communication and information exchange between all the various actors involved.
The increasing digitalization of the building process by implementation of building information modelling (BIM), virtual design and construction (VDC) etc. provides aspects of significant strategic importance for the development of new methods for information exchange and coordination between all actors in the building process [2]. BIM-based management of information helps to improve the quality of design information e.g. by clash detection of various MEP-models reducing the numbers of spatial conflicts of installations etc. [3]. With BIM and VDC, any building or construction can be visualized, simulated and analyzed already at an early phase of the construction process [4]. The fragmented and project based organization of construction provide lack of common incentives for long-term business relations and common strategies which altogether constitute examples of impediments for implementation and application of BIM [5].
Reference [2] emphasizes the need for common guidelines and consistent strategies for the development of common standards, file formats and forms of agreements, which all represent central conditions for BIM and VDC implementation. Smart Built Environment [6], a national Swedish strategic innovation program for the construction sector, brings forward digitalization in construction as the single most important development area for the construction sector today. Smart Built Environment underlines the importance of establishing coherent information exchange between the actors of construction in a broad sense [6]. Accordingly, digitalization should include the project-based construction process as well as urban planning and industrialized construction.
1.1. Problem statement
The development of an integrated digital information infrastructure for the construction sector will reach beyond the traditional project process and include the urban planning processes, where geographical information systems (GIS) are currently used, and the manufacturing processes of industrial construction supported by e.g. product data management (PDM) and product information management (PIM) systems. However, the significant difference between BIM- and GIS-models, where the BIM-model use a local separate coordinate system while GIS-models use geographical references, challenges and impedes efficient and integrative information exchange [7]. Further, the project based building process, the urban planning process and the manufacturing process of industrialized construction, represent fundamentally different production systems, which impedes the establishment of common information standards and coherent information exchange.
1.2. Purpose and objectives
This study constitutes a survey of the interface between industrialized and project based construction. The purpose and main objectives of the study are to review and map the current information exchange and business relations between industrialized and project based construction in order to identify both existing and potential areas of digitalization and standardization for improved flow of information.
The objectives of the study are expressed in the following research topics: • Information deliveries – Objects and properties
• Information exchange • Business relations
Information deliveries concerns the identification of any existing standards and classifications systems used to describe the properties of industrial components. Information exchange accounts for who shares information with whom, what information is exchanged and what file formats are used. Finally, business relations describes forms of cooperation, framework agreements, etc. between the industrial supplier and contractors.
2. Industrialized construction – processes and building systems
Traditionally, industrialized construction has been associated with mass production of building parts and components, i.e. prefabrication off-site. Over the years, industrialized construction has evolved into design and manufacturing of more complex building systems composed by a number of standardized and well-documented building components. For example, the structural framework of a building can represent a building system, composed by a specific set of slabs, walls, pillars and beams. [8]
Today, industrialized construction constitutes a systematic, controlled and standardized production process of well-defined building systems, which makes it possible to monitor and gather experiences from the design, production and assembly of the building system as a basis for continuous improvements [9]. This broad and updated understanding of industrialized construction puts focus on the process rather than on the project. Consequently, industrialized construction is not limited to prefabrication and factory production, but includes all systematic, controlled and standardized production of well-defined building systems, regardless of whether the building products are manufactured off-site or manually produced on site.
Standardized building systems render possibilities for systematic production control, i.e. industrialized construction supports learning loops and continuous improvements from one project to another [10]. Hence, working with building systems implies moving the knowledge and gained experiences from individuals to the building systems. The important issues of standardization and continuous improvements are very difficult to establish in the traditional and project-based construction process.
With building systems it becomes possible, as well as necessary, to thoroughly document the building system and its components in order to provide clear instructions for the design, logistics, and assembly processes. The documentation constitutes a link between the design and manufacturing and the final assembly of the building systems on site [11]. The documentation clarifies the delimitations of the building system, e.g. in terms of its geometrical dimensions, weight, bearing capacity etc. Altogether, the documentation contributes to the continuity and standardized working procedures and, thereby supports monitoring and production feedback. Well-documented building systems make it possible to hire external consultants and engineers in the production and assembly of the building system and still keeping the working procedures standardized. Building information modelling (BIM) is very well suited for the documentation and information exchange of the properties of the various components that constitutes a building system.
3. Research method
Two case studies have been carried out in order to review and map the information exchange and business relations between industrialized and project based construction. Both cases refer to the general interface between industrialized and project based construction, and do not refer to a specific project or situation. The first case describes industrialized construction from concrete elements suppliers’ point of view, e.g. suppliers of wall and slab elements, foundations, pillars, beams etc. and relies on input from four companies (of which one wanted to be anonymous):
• Abetong AB [12], a Swedish concrete element supplier
• StruSoft AB [13], an engineering software provider for the building industry • Tyréns [14], a Swedish engineering consultancy
The second case describes industrialized construction from the contractors’ point of view and relies on input from four contractors and housing concept developers:
• IKANO Bostad [15] • Veidekke [16] • NCC [17]
• Lindbäcks Bygg [18]
The collection of data was primarily done by semi-structured interviews, concerning the research topics presented above. Altogether, nine interviews were carried out with key-representatives from the eight case study companies. All interviews were recorded, transcribed and returned to the respective respondents as a quality check. The case related interviews were also supplemented with five interviews for a more general orientation and improved understanding
of industrialized housing concepts, digital classification systems and the professional building clients’ view on industrialization.
4. The interface between industrialized and project based construction
The following sections, which are based on the two case studies, provide a review and mapping of information deliveries, information exchange and business relations between industrialized and project based construction.
4.1. Topic 1: Information deliveries – Objects and properties
All suppliers of concrete elements produce more or less the same kind of product, i.e. walls, slabs, pillars, beams and foundations. However, despite of the almost identical product range, no common standards for classification of the various concrete elements and their properties exists. Instead, all element suppliers have developed their own company specific classification systems for their products, see examples in table 1 below.
Table 1. Examples of element suppliers naming of their different types of concrete elements. Product Supplier A Supplier B Supplier C
Wall (solid) V RV V
Wall (Sandwich) RW RW W
Pillar (circular) P or OP OP P
Pillar (rectangular) P or RP RP P
The nomenclature as well as the geometrical definitions of the various concrete elements differ between the respective element suppliers. Thus, the apparently obvious definitions of length, thickness, width and height of a concrete element are treated differently. The lack of common standards for the geometrical data impedes the description of the elements basic geometries, but it also hampers the placing of lifting components, reinforcement, holes and other things in the concrete element. Company specific standards also include the layout of drawings. The main reason for the identified differences relates primarily to the different production methods applied by the respective elements suppliers. For example, one element supplier cast pillars in an upright position while others produce pillars laying down. Accordingly, drawing layouts differ depending on the companies’ production methods.
The lack of common standards is of course most prominent for an element supplier when sharing information and drawings with external actors, e.g. the building client, technical consultants or competitors. Numerous situations Rework, i.e. waste, is generated every time an element supplier or technical consultant must change the drawing layouts from one geometrical system to another. The lack of geometrical standards also render problems when exporting and importing 3D-models between e.g. Tekla, Revit or other BIM-systems.
The increasing application of BIM-systems among element suppliers and engineering consultants enables design and management of more advanced architectural and structural element solutions. Consequently, the design of concrete elements get more advanced and unique, and improved and more flexible methods for quick adjustments of the production settings make it easier and less expensive to produce unique concrete elements even in limited volumes. Thus, the increasing variety of unique concrete elements render difficulties for the development of common standards and classification systems.
4.2. Topic 2: Information exchange
The mapping of information exchange between the supplier of concrete elements and the contractor revealed, among other things, information disruptions in the transition from design to production and some challenges that relate to the form of project coalition.
In integrated project coalitions, which is the most frequently used, the contractor can procure the element supplier at an early stage of the project. However, the contractors´ most pronounced benefits of industrialized construction
were time saving, improved working conditions and better logistics, which all directly relate to improved conditions on the construction site. Decisions about whether to choose industrialized construction methods or a traditional in-situ production alternative are thus, primarily a concern of the construction managers rather than the technical engineers in the design phase. Consequently, decisions about applying industrialized construction are sometimes taken late in the design process, with redesign as an unnecessary consequence.
The tendering documentation in this case, normally consists of simple architectural sketches distributed in pdf-files. The element supplier does not find reasons for creating a 3D-model to support their tendering calculations under these circumstances, simply because the element supplier still do not know whether they will win the bid or not.
When the element supplier is procured by a contractor in a separated coalition, the design documentation is then complete and includes architectural and structural drawings (PDF, DWG), building descriptions (PDF), an architectural 3D-model (Revit, IFC) and a structural 3D-model (AutoCAD, Revit, Tekla, IFC). The element supplier uses the tendering models for e.g. quantity take off and measures as a basis for their bid. However, when the element supplier has won the bid, they always make their own 3D-model of the structural framework, regardless of whether there were 3D-models available or not in the tendering documentation. The main reason for this obvious rework is simply that the design documentation is typically done with an in-situ produced structural framework in mind. Consequently, the element supplier needs to redesign the structural framework in order to adapt it to an industrial building system based on precast concrete elements. The given situation with two parallel design solutions raises an important question about responsibilities between the designers of the original structural framework and the industrial design, i.e. the in-situ and the precast design.
The 3D-model developed by the element supplier obviously plays an important role for the design of the structural framework of concrete elements, but it is also important for clash detection and for the coordination between the structural framework, the MEP disciplines and other aspects of the building. However, the information exchange between the element supplier and the contractor is most frequently done by sharing PDF-files or DWGs, e.g. drawings (PDF, DWG), bill of quantities (PDF, Excel), assembly instructions (PDF), production plan (PDF, Excel), delivery plans (PDF) delivery notes (PDF) etc. The transformation from 3D to 2D is also apparent internally for the element supplier, as the workers only use 2D-drawings for the preparation and casting processes of the concrete elements in the factory.
4.3. Topic 3: Business relations
The contractors’ approach to industrialized construction goes beyond the distinct roles of demand and supply, as contractors both can act as buyers of industrialized construction goods and services as well as developing and manufacturing their own industrialized building systems. This study identifies three characteristic strategies towards industrial construction among contractors, of which each represents a different business model with impact on the information exchange and need for standards and classification systems.
4.3.1. Strategy 1: Building systems - in-situ production
Industrial construction can in its simplest form, imply development, marketing and consistent use of the same standardized, tested and well-documented building system, e.g. of plaster walls, slabs, foundations, roof constructions etc. These building systems can be developed, owned and used by individual contractors, or developed and offered on the market by individual industrial suppliers of building components and services.
Gyproc [19] provides one example of a developer and supplier of building systems for the international construction market with a broad range of products such as lining systems for walls, floors and ceilings, structural steel encasement systems, various forms of plasterboard ceilings, flooring systems etc. The Gyproc Handbook [20] provides a complete documentation of all these building systems, including drawings, components, connections, fire protection, sound properties etc.
NCC [17], a Swedish contractor in this case study, applies this approach to industrialized construction. NCC’s and other contractors’ development and implementation of common and standardized building systems require commitment from all levels of the organization, in order to gain the benefits of repeated work, learning loops and continuous improvements. The approach towards industrialized construction and application of standard building
systems provide a strategically changed process that challenges the contractors’ traditionally decentralized project-oriented organization, where a culture of self-governance allows project managers to choose technical solutions and production methods on their own.
4.3.2. Strategy 2: Building systems – prefabrication by external suppliers
In the approach to industrialized construction, presented in strategy 2, the building systems are prefabricated off-site and then brought to, and assembled, onoff-site. The contractor is the developer and the owner of the building system, but the manufacturing of the building system is outsourced to external industrial suppliers. IKANO Bostad [15], one of the contractors studied in this case, applies this approach to industrialized construction. The main argument for this approach is that contractors want to control the design of the building system, but want to avoid the risk of making fixed capital investments in manufacturing facilities.
Traditionally, selection and assignment of project suppliers are done on basis of lowest bids. Fixed price contracts and focus on low-cost provide impediments for good cooperation, efficient information exchange and drive for innovations, which promote sub-optimization and productivity losses [1]. With an industrial approach, the short termed and project delimited procurement is replaced with more long-termed business relations. The contractors’ development and implementation of a building system constitutes a long-term commitment that goes beyond the scope of single building projects. Thus, it is important for the contractors to establish framework agreements with one or a number of industrial suppliers in order to ensure sufficient supply of the building systems. Long-term relations with the contractors are, on the other hand, equally important for the industrial suppliers in order to ensure a consistent demand and reduce the risk of required investments in manufacturing facilities. As part of the framework agreements, unit prices for the various parts of the building system are agreed and fixed, which facilitates and supports procurement of building systems and service for individual projects.
One advantage with a framework agreement between the contractor and the industrial supplier is that it enables very early involvement of the industrial supplier. The contractors in this case present some good examples of when element suppliers were involved in the contractors’ early bidding process for building projects. This enables adaptation of the contractors’ bid with respect to the cost, time, logistical and other consequences of industrial building systems suggested for the project. Further, early involvement and decisions about building systems for a project helps to avoid the rework for transforming an in-situ design to a prefabricated design.
4.3.3. Strategy 3: Building systems – prefabrication internally by the contractor
The third approach to industrialized construction account for the strategy in which contractors develop their own building system and manufacturing facilities. With this approach, the contractors have full control of the design, performance and manufacturing of their building systems and can thus gain all the benefits from the standardized and controlled work processes and continuous improvements. However, in this approach the contractors also carry all the economic risks related to the fixed capital investments and operation and maintenance of the manufacturing facilities. Lindbäcks Bygg [18] and BoKlok [21] are examples of companies in this study that have adopted this approach to industrialized construction. Lindbäcks Bygg [18] describes itself as an industrial contractor that develops and manufactures housing structures with wood frame structural system in volumetric sections. BoKlok [21], owned by IKEA [22] and Skanska [23], has developed its own housing concept, which is also based on volumetric housing sections. Both companies control the whole value chain, i.e. the development of the housing concept, initiation of projects, off-site manufacturing and on-site assembly of the volumetric housing sections, besides the marketing and sale.
The need for a continuous and integrated exchange of information and well-documented products and processes are equally important regardless of whether the approach to industrialized construction is run internally or involves external suppliers. However, when controlling the whole value chain, as described in this strategy, the establishment of common standards, classification systems and communication becomes solely an internal matter. Consequently, the issue of information infrastructures become less problematic compared to the earlier strategies in which the contractor interact with external industrial suppliers.
5. Conclusions
The study concludes that there is room for improvements in the interface between the industrial supplier and contractors. The identified lack of common standards and classification systems provide impediments for efficient information exchange and generate recurrent rework and re-entering of data. PDF, Word or Excel files, and to some extent DWG’s, represent the most frequently used file format for information distribution, while IFC, 2D or 3D-formats still are used occasionally. The ongoing digitalization and development of standards and classification systems for the construction process need to include and consider industrialized construction in order to facilitate information exchange and to enable the full benefits of industrialized construction.
The most prominent need for improvement, expressed by the respondents in this study, is however the development of new business models. Both industrial suppliers as well as contractors call for closer and more long-term business relations that extend beyond single projects. Besides, industrial suppliers want to involve early in the projects, share the risk and rewards with the contractor, and extend their business offers to include industrial products as well as services in terms of design, technical support, logistical solutions, maintenance etc. Conclusively, implementation of new business relations is brought forward as a driver for the establishment of common standards and classification system.
Acknowledgements
This paper is based on a research project carried out from 2015 to 2016. The project, named “Survey of Industrial Processes”, represents one of four pre-projects within the Swedish strategic innovation program of Smart Built Environment [6]. The research as well as the strategic program is financed by VINNOVA [24], The Swedish Research Council Formas [25] and Swedish Energy Agency [26].
References
[1] G. M. Winch, Construction Management, Wiley-Blackwell, 2010.
[2] A. Ekholm, H. Blom, K. Eckerberg, K. Löwnertz och V. Tarandi, ”BIM – Standardiseringsbehov,” SBUF ID:12690, 2013.
[3] R. Jongeling, ”BIM istället för 2D-CAD i byggprojekt: en jämförelse mellan dagens byggprocesser baserade på 2D-CAD och tillämpningar av BIM,” Luleå Tekniska Universitet, Luleå, 2008.
[4] J. Bröchner (ed.), ”Bygginnovationers förutsättningar och effekter,” VINNOVA – Verket för Innovationssystem, 2012.
[5] G. Qvarnström, ”BIM och avtalsformer - En jämförelse mellan befintliga avtalsformer och Integrated Project Delivery, IPD.,” OpenBIM, Stockholm, 2012.
[6] Smart Built Environment, ”Smart Built Environment,” 21 06 2016. [Online]. Available: http://www.smartbuilt.se.
[7] M. Fredriksson, ”Integrering av BIM och GIS med spatiala databaser - En prestandaanalys,” Institutionen för Naturgeografi och Ekosystemvetenskaper, Lunds Universitet, Lund, 2014.
[8] H. Lidelöw, D. Engström, J. Lessing och L. Stehn, Industriellt husbyggande, Lund: Studentlitteratur, 2015.
[9] J. Lessing, ”Industrialised House-Building, Conceptual Orientation and strategic perspectives,” Faculty of Engineering, Lund University, Lund, 2015.
[10] H. Johnsson, “The Building System as a Strategic Asset in Industrialised Construction.” 6th Nordic Conference on Construction Economics and Organisation, 2011.
[11] G. Jansson, H. Johnsson, D. Engström, “Platform use in systems building.” Construction Management and Economics, 32, 70-82. 2014 [12] Abetong AB, “Om Abetong”, 01 06 2016. [Online]. Available: www.abetong.se.
[13] StruSoft AB, ”Om StruSoft,” 23 05 2016. [Online]. Available: www.strusoft.com. [14] Tyréns AB, ”Om Tyréns AB,” 23 05 2016. [Online]. Available: www.tyrens.se/sv/.
[15] IKANO Bostad, ”IKANO Bostad AB (SE),” 06 03 2017. [Online]. Available: www.ikanobostad.se. [16] Veidekke, ”www.veidekke.se,” 01 06 2016. [Online]. Available: www.veidekke.se.
[17] NCC, ”NCC AB (SE),” 06 03 2017. [Online]. Available: www.ncc.se.
[18] Lindbäcks Bygg, ”Lindbäcks Bygg,” 01 06 2016. [Online]. Available: www.lindbacks.se/bygg. [19] Gyproc AB, ”Om Gyproc,” 07 06 2016. [Online]. Available: http://gyproc.se/om-gyproc.
[20] Gyproc Handbok, Gyproc Handbok – System för lättbyggnadsteknik, utgåva 8, upplaga 1, Gyproc AB, 2010. [21] BoKlok, ”BoKlok,” 01 06 2016. [Online]. Available: www.boklok.se.
[23] Skanska AB, ”Skanska,” 01 06 2016. [Online]. Available: http://www.skanska.se/. [24] Vinnova, ”Vinnova,” 01 06 2016. [Online]. Available: http://www.vinnova.se. [25] FORMAS, ”FORMAS,” 01 06 2016. [Online]. Available: http://www.formas.se.
