Building Information Modelling (BIM) has been advocated for its potential delivery of more innovative, cost-efficient buildings through more integrated information and collaboration. Yet the inherent power of BIM is its potential contribution to the design, construction and commissioning of buildings with lower environmental impacts, whether this is in the form of energy-efficiency, the cutting of carbon or for better use of fewer materials.
There are obvious advantages: immediately drawing in three dimensions allows the cutting of 2D and 3D sections pretty much anywhere in the building design. This means that thermal bridging and odd detailing can be noticed swiftly and resolved prior to construction, leading to better performing and more energy-efficient buildings.
However, I am not just talking about the power of 3D CAD drawings, but the use of BIM enriched with additional information and integrated analysis and evaluation tools. This might include daylighting and solar studies, material and product libraries containing embodied energy and Life Cycle Assessment (LCA) information, as well as de-construction, maintenance and building management information for the entire lifecycle of a building. If BIM allows us to understand how to put a building together better, then it should also allow us to have a better grasp of how that building should perform and later, how it might be taken apart.
BIM gives access to automatically calculated and current design data useful for environmental and heat-loss analysis, such as floor and surface areas and building volumes. For optimum effect, it should be formally integrated with Building Performance Evaluation (BPE), and Post Occupancy (POE) stages and feedback. The latter is proposed to be aligned with BIM through the Soft Landings framework by the UK Government.
Equally, BIM’s advantages are not the construction industry’s “silver bullet”, but a tool that is only fully realised through collaboration throughout the entire inter-disciplinary design team from the early design stages. This shifts specialist consultants’ resources to earlier stages, and as I noted in the Environmental Design Pocketbook, such early support and input in the design process usually advances better integrated, sustainable building design.
Once BIM-integrated evaluation, analysis and compliance tools are created, different design options could be more easily compared. This should lead to better informed decision-making at early stages, reducing the risk of abortive design or the bolting on of ‘eco-design features’ (which are inherently less cost-effective) in later stages.
BIM’s potential for integrated sustainable design will hinge on the integration of reliable, up-to-date, research-based information and the embedding of trust-worthy evaluation tools. For example, BIM models could contain a vast library of embodied energy and LCA information, which would make the environmental and lifecycle comparison of different material and product specifications vastly easier than a manual calculation, as well as provide information for assessments (such as % of materials with a certain specification).
Additionally, when substituting materials or products at later work stages, the impacts of doing so should be much more transparent to all parties, because the total building’s environmental impact/profile will automatically change with each iteration. If we entrust decision-making to be underpinned by this embedded information, it will be crucial for it to be reliable, comparable and up to date; but at present there are no perfect embodied energy or LCA tools available.
Tying BIM back to the building’s commissioning and occupation stage is also promising, where estate managers can gain access (and add) to the BIM information to seasonally commission and maintain the building – rather than rely on an often incomplete and complex paper archive.
The key to BIM’s power will be accessibility to reasonably priced software licenses now and in the future, in addition to trained and knowledgeable professionals (including estate management teams) and a resolve to create and maintain ever-growing libraries and tools, which must remain up to date and reliable.
BIM’s potential for integrated sustainable design will hinge on the integration of reliable, up-to-date, research-based information and the embedding of trust-worthy evaluation tools. For example, BIM models could contain a vast library of embodied energy and LCA information, which would make the environmental and lifecycle comparison of different material and product specifications vastly easier than a manual calculation, as well as provide information for assessments (such as % of materials with a certain specification).
About this article
Sofie Pelsmakers was invited to write this opinion piece for the NLA/NBS 'Green BIM' conference, 31 January 2013.