Implementing building information modelling: a case study of the Barts and the London hospitals

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1 icccbe 2010 Nottingham University Press Proceedings of the International Conference on Computing in Civil and Building Engineering W Tizani (Editor) Implementing building information modelling: a case study of the Barts and the London hospitals Chris Harty Innovative Construction Research Centre, University of Reading, UK David Throssell, Howard Jeffrey & Malcolm Stagg Skanska Technology, UK Abstract We present a case study of a major contractor, Skanska, implementing BIM on two large hospital projects in the UK: the Saint Bartholomew and the Royal London. We argue that BIM is a set of practices or activities, rather than just a set of technologies, and describe the new ways of working that emerge through the implementation process. We focus on ways BIM activities were developed to bridge gaps; between designer and contractor; between office and building site; between construction and O&M. It also describes how BIM moved from being a collaborative space for exploring design solutions, to a roadmap for the construction process, or a central index of design and construction information for the projects. The paper begins by describing the Barts and the London projects, and the imperatives which led to the decision to adopt BIM practices on them. It then discusses some of the new ways of working that are being implemented on the project. This discussion draws on both the experience of those authors involved in the implementation process, and a set of interviews conducted in 2009 as part of a University of Reading study. It focuses on the ways that Skanska as a contractor developed ways of utilising existing BIM information in areas such as design reviewing, handover processes and planning equipment installation. Keywords: building information modelling, BIM, case study, implementation 1 Introduction The potential to be gained through better integration and coordination of design and construction information has long been understood within the construction sector (e.g. Higgin & Jessop, 1965). Currently, Building Information Modelling (BIM) technologies are being heralded as able to provide this increased integration, and the business case for their adoption in terms of saving rework and avoiding costly errors is highly persuasive. The benefits of a complete and accurate source of design and construction information are also being extended into the operation and maintenance of these facilities. However, the uptake of these technologies within the sector is partial and fragmented, and the projects which have made a commitment to project-wide implementation of BIM oriented ways of working are few and far between (one example is the new Terminal 5 at Heathrow: see Harty, 2005; 2008). Perhaps because of this, although BIM is increasing being discussed in both academic and practitioner oriented literature, there is little detailed description of the benefits and challenges of implementing BIM on large projects, especially from the point of view of the contractor.

2 2 Building information models (BIMs) The idea of integrated BIMs are currently the subject of increasing interest within construction circles, but the sector has for a number of years been utilising various information and visualisation technologies to support construction activity (Whyte, 2002). Computer Aided Design (CAD) is standard practice, and this is increasingly undertaken in three dimensions, especially when designing and representing complex areas (such as plant rooms) or complex elements (such as building services or intricate architectural designs). Various 3D representation tools are regularly used to communicate design ideas to clients. Similarly, electronic communication, extranets, collaboration software and document management systems can all be seen in use, especially on large or complex projects. Although these tools promise the integration of the production, sharing and representation of information in construction projects, in practice there seems to be a gap between their possibilities and the ways they are actually utilised. Partly this may be down to a lack of consistency when it comes to defining what BIM is, and what doing BIM involves. A high level of integration and interoperability between these applications, to effectively join up the design and construction processes, to re-use the same information down the supply chain and to digitally mediate construction activities is required. But this level of integration requires the development of coherent practices and processes, as well as the actual BIM tools. So Eastman et al s (2007) BIM handbook defines BIM as a modelling technology and associated set of processes to produce, communicate and analyse building models (Eastman et al, 2007: 13). The concept of the BIM is representing more than just the use of various technical tools; it includes the processes which support their use. Going further, Jernigan states BIM is the management of information and the complex relationships between the social and the technical resources that represent the complexity, collaboration and interrelationships of today s organizations and environment. The focus is on managing projects to get the right information to the right place at the right time (Jernigan, 2007: 23) In short, BIM is as much, if not more, about people and processes, as it is about technology. Therefore we see BIM as a socio-technical system (Trist & Bamforth, 1951) where the technological tools and the social practices (of use; of management) are mutually dependent and mutually shaped though use. This approach avoids problems of exploring the challenges of implementation from either a technological or social approach, rather investigating the socio-technical practices which emerge from implementation and use. 3 Empirical context The project from which the empirical material below is taken involves a combination of refurbishment and new build work across two London hospitals, with a total value of approximately 1 billion. The project involves the construction of two new state-of-the-art hospitals on separate but existing hospital sites in Central London covering a built area of 270,000 m2. In total the hospitals will hold over 1200 beds and employ 7000 staff (see also Huberman and Throssell, 2008). There are a number of issues of note with this, in addition to its size and complexity. As a hospital project, it must satisfy the plethora of different users of the finished facility; patients, doctors, nurses, admin staff and visitors, as well as the NHS trust acting as client. Also, facility management is a challenge given both the high levels of use of medical facilities, and the complex services and equipment which will be installed. In addition, the sites are architecturally sensitive, and being located in central London imposes constraints for the construction process itself, in terms of site access, delivery of materials and minimising disturbance of neighbours. Finally, a condition of the contract being awarded was the generation of savings on the total project cost in the order of 10%. It is the meeting of these challenges that has resulted in a significant attempt to develop new ways of working which effectively utilise BIM information coordination and management tools.

3 4 BIM technologies in practice To date, the research has concentrated on investigating specific areas where the project s main contractor has implemented BIM technologies, focussing on the development of new ways of working which utilise these artefacts The approach taken by the contractor has been to look for particular areas where realising the potential of BIM oriented practices could generate visible advantages, respond to specific challenges experienced on the project, or align with a particular business case. Three specific applications of BIM technologies and the socio-technical practices which are emerging through their implementation are therefore sketched out below. They each involve integrative activity across different actors within the project, ranging from design through to facility management and new ways of sharing and utilising construction information. But these applications all depend on production of consistent shared information across the project, enabled through a central repository and on the development and use of inter-operable tools. These are more generic, project wide requirements upon which these specific applications hinge. Although BIMs are often associated with CAD modelling, in order to enable the coordination of building information, a detailed repository or database is a fundamental technological requirement. It is from the database that multiple representations of the data are drawn, whether as, for example, CAD models or schematics, bills of quantities, spreadsheets of calculations, or schedules of work. Through utilising information from the database, each of these representations contains up-to-date information from the same coordinated source. Populating the database with the relevant information is therefore crucial; if information is incomplete or out of date, representations and coordination will be inaccurate, and the efficacy of BIM technologies is greatly reduced. This is just one example where it is the practices around these technologies and which manage the information in the repository, and not the technologies themselves, which are vital. One such practice developed on the project is the delivery of all design work as 3D models, rather than 2D schematics 1. These are combined into a single, coordinated 3D model, with various intelligent attributes added to specific components. This model can then be interrogated to provide a huge range of information, such as whether elements of the design are spatially coordinated, where specific components are located across the facilities, component part numbers, specifications or servicing schedules, and so on. Having a coordinated central store of project information requires significant effort the cost of setting up such a system is estimated at around 0.5% to 1.5% of the total project value. However, doing so enables a number of new ways of managing and using project information, with the promise of significant cost savings, and reduction of risk. It is to some of these new emerging practices that we now turn. Each of the following vignettes describe the ways various actors and BIM technologies are being assembled and shaped, and the new ways of managing information and collaborating across the project emerging from these interactions. 4.1 Virtual snagging Clash detection combining models from different disciplines and checking their spatial coordination is now a well established technique. But the navigation of a fully coordinated model of the facility offers further benefits. The process of constructing complex facilities can present unique and unforeseen problems. These often emerge on site, as problems of access, undocumented changes in completed work, or the need to go back to engineers to verify possible solutions to inconsistent information can lead to considerable and costly delays. Reducing these problems is therefore a significant factor in reducing overall project costs. This particular project also involves a significant amount of refurbishment, as well as new building work, which can present further problems of 1 Interestingly, a number of very small consultancies have sprung up to convert 2D schematics to 3D models, where organisations are unwilling or unable to provide 3D models directly to the contractor. This is especially the case in the area of building services design.

4 installing new components within existing, often constricted, spaces. To address these issues, the project s central model is being used to perform a virtual troubleshooting or virtual snagging of the designs before on-site installation or fabrication of components begins. Weekly CDM (Construction and Design Management) reviews are held to check across various parts of the on-going design for a range construction problems. These include ensuring there is adequate access to install new services, and to perform health and safety assessments looking for trip hazards, inaccessible components, room to erect ladders and platforms and so on. Any particular problems are red-lined marked up on the model - and then go back to the designers for amendment. There is a growing list of several hundred of these issues which have been discovered and resolved so far. Without the CDM process such problems would not be discovered until actual on-site installation, causing potential delays through having to re-route, reposition or even re-fabricate components. The meetings, focussed on the virtual model, enable project managers, designers and engineers, data managers and, increasing, facility managers to interact with the model, and to input into the design review process; effectively developing a set of practices through which actors across the construction supply chain are involved much earlier than is usual. The long-term operation and maintenance commitments in PFI projects (35 years on this particular project) means that the contractors take on responsibilities which extend beyond construction and hand-over. By integrating facility managers into design reviews, they are developing designing and building practices which can lead to facilitates which are easier, and hence cheaper, to operate and maintain. It has also been noted that by being able to navigate through the virtual model live on a large screen has encouraged a more interactive process with more collaborative discussion and input into the review. 4.2 Construction monitoring and planning An important aspect of monitoring complex projects is in providing robust comparisons between planned activity and actual work completed. This is essential to keep track of progress, and to flag up and mitigate for any delays, but is often complicated to coordinate as a paper based activity distributed between building sites and project offices. However, on this project the BIM repository already contains the planned sequences of work. These are then used to produce an animation of the facility being constructed over time, therefore showing how the on-site work should be undertaken, according to plans of work and contractual obligations. Alongside this, actual work started and completed on site is recorded weekly via hand-held devices. This is fed back into the BIM, and is used to produce a comparative animated model showing actual activity on the site over time. These two models are then run side-by-side to check actual against planned activity. This allows progress against plan to be easily monitored, rather than having to laboriously cross reference planned sequences of work with progress reports. Monitoring and recording handovers from design to construction is also a significant activity. For each room, 83 separate handovers are required, and each has to be recorded and signed off. A paperbased process involves 12 A3 printouts per room, which have to reflect the latest design changes so if amendments occur these papers have to be reprinted. Bearing in mind that there are 6225 rooms across the two hospitals, this is both a very resource intensive task, and one that is very difficult to keep track of. An alternative set of practices is being developed on the project, again using hand-held devices linked to the BIM repository, rather than paper. As for the monitoring and planning application, the BIM contains details of expected and current work. The hand held device allows managers on site to access this information live from the repository (so hence it is up-to-date) and a customised menu on the model viewing application is used to input dates of completion and handover, or current state of work and expected completion. This information is automatically transferred back into the repository. Not only has this vastly reduced the effort required for checking status, but also solves the problem of managing what would have been vast amounts of paper based information and

5 avoiding costly errors. It is also another example where site based activity and actors are being incorporated into these new practices around the BIM tools. 4.3 Working with medical planners A key challenge in hospital construction is the installation of large pieces of medical equipment, such as MRI scanners. These are generally supplied complete, and cannot be broken down and reassembled wherever they are to be located. Furthermore, on this project they have to be installed less than six weeks before the opening of the hospital. In the past, as large equipment has arrived on site various access problems have been experienced, leading to removing partition walls or suspended ceilings, or even having to grind concrete floors down to give enough room to get the equipment in situ. This deconstruction of course must then be reinstated, a costly and time consuming activity. To avoid these problems, virtual models of the facilities as they will be at time of delivery are extracted from the BIM repository, again using updated planned and actual models of work completed. Working with the medical planning team, a virtual scanner of the correct dimensions can then be pushed through the hospital model, and any clashes or areas with less than the required access can be identified. In doing this, a large number of such issues have emerged, which are then red-lined and go back to the relevant designers to amend either design or planning sequences to ensure that the equipment can be installed without any rework of the facility. Not only will this avoid costly problems, but again represents the development of the BIM new practices which involve parties who are not usually engaged with until much later in a project. 4.4 Material take off The cost planning, commercial and environmental teams have benefited from the swift extraction of quantities and material lists from the model. The model has been used to provide quantities of the Architectural finishes including, ceilings, floors, skirtings, wall protection, internal partitions, doors, opening hatches, windows, external cladding and curtain walling. All the structural elements of the concrete and steel frames have been quantified and to date the sanitation, HVAC and all the elements on the modular services have been extracted. A particular success has been the use of the quantities by the environment team who have used the data to set an ambitious 10% waste target for sub contractors. With accurate data and a method to check and weigh waste removed from site the team have been able to set up an incentive scheme with the aim of beating the 10% target. Measurements have already shown that these targets are being bettered. 4.5 Making the data work harder The re-use of the design data has extended to the supply chain. With some simple export / import computer code written for the task, design data from the 3D partition objects was used to populate the sub contractors estimating system. The result was an accurate price and 6 week saving on the tender programme. Those same partition models are being used on site to record progress using a Tablet PC with a simple 2-click interface the resulting database is used to agree monthly valuations with the subcontractor. 4.6 Modular services Another example of supply chain engagement is the adoption of modular services in the corridors. The services designers and module manufacturers have worked together to ensure that the services are modelled to suit standard modules, thus saving time often spent re-designing and re-routing services to fit and therefore reducing the time between issue of information to manufacturer and delivery to site.

6 5 Conclusions The BIM model on The Barts & London project is not the innovation, rather it is in the unlocking of the value of the 3D objects that make up the combined models. The project team has realised that in addition to clash and fit, interactive models can be used to: check for safe access for operation and maintenance; confirm major plant and medical equipment installation/removal strategies; link to construction programmes and monitor progress. Furthermore, the CAD objects can be interrogated to swiftly and accurately extract quantities and material lists. This has been used to re-inform the cost plan, challenge trade contractor tender prices and enable the Environment team to set ambitious waste targets on the basis of robust data. Another use of the data has been to link design information direct to Trade Contractors estimating software, thus saving time on the tender programme. Finally, the building services model has been a key driver in the decision to use modular services in the corridors which will lead to a significant programme saving. The BIM model started as a method of ensuring spatial coordination but turned out to be a tool to improve quality, reduce costs and waste, save time and improve Health and Safety for the end user. Importantly, it is not the technology which has driven these innovations, but the appropriation of these tools into new ways of working, managing and collaborating across the project. References EASTMAN, C., TEICHOLZ, C. P., SACKS, R. and LISTON, K. BIM handbook: a guide to building information modeling. John Wiley & Sons, New Jersey. HARTY, C., Implementing innovation in construction: Contexts, relative boundedness and actor-network theory. Construction Management and Economics, 26, HARTY, C., Innovation in Construction: A Sociology of Technology Approach. Building Research and Information, 33(6), HUBERMAN, M. and THROSSELL, D., Collaboration through building information modelling. Space craft: Developments in architectural computing. D. Littlefield. London: RIBA. JERNIGAN, F., Big BIM little bim. Salisbury, MD: 4Site Press. TRIST, E. L. and BAMFORTH, K. W., Some social and psychological consequences of the long-wall method of coalgetting. Human Relations 4, WHYTE, J. K., Virtual Reality and the built environment. Oxford: Architectural Press.