Understanding the Potential of BIM to Support Heritage Asset Management - 22/05/2019
Research undertaken under a collaborative doctoral partnership between Historic England and the University of Reading is moving beyond the field of 3D data capture for digital preservation. It considers how critical information for the conservation, repair and maintenance of historic buildings can be visualized in 3D BIM models and how BIM processes can be used for the management of structured datasets that inform conservation and repair programmes. A pilot study has been conducted using the work of the UK Antarctic Heritage Trust and historic British research base ‘E’ on Stonington Island, Antarctica, to consider this potential.
Building Information Modelling (BIM) is a process of information production, management and delivery among project stakeholders. It facilitates collaborative working practices through defined processes and technology, offers the potential for improved performance and efficiencies and thus, huge benefits to the construction industry. With the Government agenda to meet BIM level 2 compliance and, drawing from the increasing use of BIM in design and construction, the use of BIM technology with existing and historic buildings has been researched for the past decade. This clearly offers benefits for conservation management.
BIM Application in the Heritage Sector
BIM application in the heritage sector to date has had a heavy focus on digital documentation of heritage assets fuelled by technological developments in 3D data capture such as photogrammetry and laser scanning. There are numerous exemplars of heritage assets being documented in this way and the range of benefits in visualization, structural and condition monitoring, education and research for conservation practice are becoming well understood. Research has considered the practical issues of data capture, subsequent 3D parametric modelling from point cloud data, automated data processing, pattern recognition, and the creation of object libraries.
However, the potential of BIM as a centralised data hub, facilitating the production, integration and management of required building information such as survey data, material, constructional and performance analysis, drawings, photographs, historical information and archival data, is an important aspect of recent research that deserves further exploration. When data and information is produced or collated in relation to a project or asset it can build up rapidly. Traditional methods to produce paper-based files or digital pdf documents can be difficult to manage and can get misplaced or missed by individual project stakeholders. Furthermore, information and documentation in this format does not facilitate efficient analysis, planning and decision making. Key BIM concepts such as component-based parametric modelling and associated data parameters, inventory and database development and the extraction and transfer of structured data to Asset Information Models (AIM), allow for the development of a comprehensive knowledge base that could be extremely beneficial in the operational phase of a building’s lifecycle, particularly for repair and maintenance. These are explored further.
An Antarctic Case Study
Established in 1993, the UK Antarctic Heritage Trust (UKAHT) is tasked with the almost impossible mission of preserving the remains of over 70 years of British scientific exploration and research on the Antarctic Peninsula. Faced with the hostile conditions of the Antarctic climate such as katabatic winds, freezing temperatures and sea ice, even getting the more than five tonnes of equipment to these remote bases is an accomplishment. In the face of such adversities, UKAHT have taken on the challenge of managing six historic sites and monuments (HSM) and embarked on a comprehensive survey, conservation and maintenance programme of the buildings and artefacts.
UKAHT’s portfolio had been managed prior to this with what can be best described as ad hoc maintenance work. Basic historic reports were used as guiding documents for conservation decisions and repair philosophy and conservation work was recorded in annual worklists and end of season reports. However, with the appointment of a new CEO in 2014, it was decided that a more informed and managed approach to the conservation of the sites within the portfolio, and the way the trust executed their responsibilities, must be established. Most importantly was the Trust's ambition to collate a comprehensive set of base data about the historic sites, including measured survey, condition survey, material sampling, digital recording and artefact audits. Central to achieving these aims would be the development of a new digital data management system.
The pilot study considers the BIM concept of component-based parametric modelling and the application of data parameters to produce structured datasets for heritage asset management. The addition of bespoke ‘conservation’ data parameters, such as element condition, significance and urgency of repair/maintenance, can be used as a visual planning tool within the model and is particularly useful for analysing and interrogating data for the planning of programmes of conservation/repair. Furthermore, this data can be extracted in a structured format to be added to the digital AIM and imported into existing property management systems offering a single source of validated data to support asset management activities.
The Pilot Study
An assessment of logistical difficulties, freezing temperatures and unpredictable weather conditions preceded the decision to use photogrammetry to capture 3D data of the historic huts. A three-week period, an ingenious homemade telescopic pole and the use of coloured tape and food cans as survey points was the sum total required to complete the data capture. Agisoft Photoscan was used to process the digital images and generate 3D spatial data in the form of a point cloud. SketchUp was used to create the initial 3D model from the point cloud. 3D data capture and modelling were arguably the most straightforward steps in the overall process. Technological developments and research in this field means that these processes are now well understood.
Adding data parameters to a BIM model of an existing building was a process that required more thought. With a view to adding component data retrospectively, it was first important to consider the critical information requirements for heritage asset management and thus, a framework of ‘conservation’ data parameters. Structuring data in a component-structured asset data capture spreadsheet (similar to a COBie information and data exchange template) was the next important task. The project team decided to break the built assets down into building components and use Uniclass 2015 to classify and structure the data. The ‘asset data capture spreadsheet’ was then developed which would act as the overall ‘database’ in which data from visual condition surveys (conservation data parameters) and the supporting reports would be entered against the building components.
Challenges and… Surprises!
During the Stonington Island field season, a number of challenges and surprises associated with the introduction of new processes and data capture objectives were encountered. Firstly, the focus on 3D data capture and modelling aspects of BIM as opposed to the potential of BIM as a way of structuring and managing building data. This highlights the need for education in BIM as an information management tool and has contributed to the development of the new Historic England guidance document – Heritage BIM: Developing an Asset Information Model, which will assist other heritage industry professionals consider their future digital asset management strategies.
Field seasons in Antarctica are relatively short given the extreme weather conditions and as such, time is precious. Individuals have a role to play and tasks to complete. The conservation carpenter’s energy was spent carrying out urgent repairs whilst the weather was good, leaving little time for survey and data capture. In terms of a BIM information management process, this challenge identifies the need to determine roles and responsibilities and highlights the importance of the Information Manager.
Finally, the impact that inanimate objects such as ‘jerry cans’ can have on a BIM process is both surprising and critical. The realization two days into the crossing of the Drake’s Passage that the team’s fuel supply was missing, the effect the cold temperature has on laptop batteries and, the impact of incompatibility between different laptops and hard drives illustrates an actor-network effect that must be considered for future research that considers BIM implementation.
Outputs and Next Steps
The pilot study has a number of extremely useful outputs. Base E, Stonington Island has now been digitally documented for future generations to benefit from. 3D data capture allows for a number of further outputs such as 3D virtual tours of the site, thus enhancing public awareness. Also the development of highly accurate CAD drawings, 3D models and orthographic projections that can be used for the planning of conservation, repair and maintenance, and for the pre-fabrication of replacement building components such as window shutters.
The study has contributed to the development of framework ‘conservation’ data parameters for use by heritage organizations when developing BIM models and where there is an intent to manage condition survey data and asset management within a BIM environment.
Future research will look to add developed ‘conservation’ data parameters to a parametric model and consider the benefits of using this visual method for the planning of future conservation/repair.
Thank you to the UK Antarctic Heritage Trust who have supported this pilot study along with the British Antarctic Survey, Mapping and Geographic Information Centre (MAGIC) for their expert advice and assistance in digital data capture and processing. Also, to Historic England and the University of Reading who are supervising the Collaborative Doctoral Award.
This article was published in Geomatics World May/June 2019Last updated: 23/10/2019