The origins of building information modelling (BIM)
Building information modelling (BIM) has been around in various forms since the 1970s. It’s used by many construction stakeholders to generate and oversee computer-generated representations of the projects they’re designing, planning or working on.
Becoming a recognised term in the early 2000s, its place in the UK’s design and construction industries became cemented in 2016, when the government required that suppliers “tendering for centrally procured government projects, including buildings and infrastructure, be competent in BIM.”
BIM has proved an indispensable boon to the construction sector, not least in the design phase. It speeds up processes, creates greater certainty around delivery and supports the sector as it seeks to complete projects more efficiently, to schedule and within budget.
What is openBIM?
Inevitably, BIM has evolved over the years, and openBIM is a step up from the technology’s original iteration.
According to buildingSMART, the organisation that initiated and champions openBIM, the latest form of the technology “extends the breadth and depth of the use of BIM by creating common alignment and language.
“Technical applications developed for openBIM improve the management of data and eliminate disconnected workflows [and] independent quality benchmarks ensure reliable open data exchanges,” according to buildingSMART.
What are the practical benefits of using openBIM?
Outlining openBIM’s advantages, buildingSMART says the technology’s principles recognise that:
- Interoperability is key to the digital transformation in the built asset industry
- Open and neutral standards should be developed to facilitate interoperability
- Reliable data exchanges depend on independent quality benchmarks
- Collaboration workflows are enhanced by open and agile data formats
- Flexibility of choice of technology creates more value to all stakeholders
- Sustainability is safeguarded by long-term interoperable data standards
Technology conglomerate Nemetschek Group, which owns Bluebeam, has its own take on things. It backs many of buildingSMART’s assertions, but adds that interoperability between project stakeholders shouldn’t be used as grounds for competition; instead, it should be brought about via development and support of openBIM standards.
Rigorous testing and certification criteria are a must for quality support of such standards, according to Nemetschek, while proprietary format mandates must not be used to exclude candidates from project work.
Nemetschek stresses that “free choice of software in project work must be a basic right for any project stakeholder,” while stakeholders ought to “publicly endorse and promote openBIM in the architect, engineering and construction sectors.”
How does openBIM differ from what most might call “normal” or “closed” BIM?
For starters, openBIM isn’t software dependent. While its predecessor required stakeholders to use the same digital platform when working on a project, openBIM allows the transfer of data whatever platform is being used. It can work on any platform using a file format called the Industry Foundation Class (IFC).
According to buildingSMART, IFC is standardised by the International Standards Organisation, and the rules establishing a common standard allow the construction, engineering and design communities to benefit from a common language to export and import data. It adds: “IFC is a globally adopted data schema and has been adopted on a multitude of projects spanning asset types around the globe.”
Choosing between openBIM vs. closed BIM
So how do “normal” or closed BIM and openBIM stack up?
HMC Architects highlights that ordinary BIM has been used in the design process to enable architects to experiment with their ideas and identify potential issues before committing their ideas to the construction process.
It also opens the door to cost savings through reliable estimates, better workflows, improved communications between stakeholders, better opportunities for the deployment of modern methods of construction and better results through more accurate estimates and schedules.
BuildingSMART says openBIM extends these benefits of BIM “by improving the accessibility, usability, management and sustainability of digital data in the built asset industry,” in part by being nonproprietary.
OpenBIM “empowers stakeholders to develop new ways of working by transforming traditional peer-to-peer work processes. By breaking down data silos, openBIM can greatly improve project delivery and asset performance.”
OpenBIM “removes the traditional problem of BIM data that is typically constrained by proprietary vendor data formats, by discipline or by the phase of a project,” buildingSMART adds.
Some believe both technologies have advantages. According to Kathrin Köhler of Mendel University in the Czech Republic, “if it is ensured that plans are always worked out together with the same partners and if one cooperates under the same responsibility and liability conditions, closed BIM might be an optimal solution.
“But other cooperation models and constellations enable a higher degree of freedom. In these cases, openBIM might be the optimal solution due to its high flexibility and the use of the standard data format IFC,” she adds.
OpenBIM and closed BIM “are characterised by the fact that all planning partners need to pre-define which information should be shared at which time. The comparison of open and closed BIM shows that each working method has its own advantages.”
