Winner
A Design Decision Support Tool to Visualise Embodied Carbon at Early Design Stage
Words by Killian Collins ACIAT, Technological University Dublin
Designers play a crucial role in promoting sustainable design. Automating the calculations of embodied carbon and visualising the impact of materials can encourage better design decisions. As designers increasingly recognise the crucial role of the built environment in combating climate change, the use of Building Information Modelling (BIM) technology can become pivotal. BIM offers a transformative approach to design and construction processes through digital models and now data visualisation. With the urgency of addressing embodied carbon emissions in construction, this research aims to develop an automated BIM workflow that enables designers to visualise and mitigate the environmental impact of material selection within domestic construction projects in Ireland and the UK, aligning with national targets for emissions reduction by 2030.
Using comprehensive data mapping and digital visualisation tools, problematic areas in material selection are identified, allowing for informed material substitutions that can significantly reduced the building’s carbon footprint. The author has developed a tool and process that technical building designers can use to identify selected materials and the validated embodied carbon values of these materials. Streamlining BIM workflows for embodied carbon assessment within digital construction designs is crucial in any BIM mandate. In January 2024, BIM requirements in Ireland will be part of the scope of works for consultants hired to plan and manage the construction of public works contracts worth more than €100 million and over a fouryear period cascade down to projects under €1 million. It is noted that the UK construction industry is four years ahead of its counterpart in Ireland.
Greenhouse gas emissions in Ireland have increased by 9.2% from 1900 to 2022 with a 2 million tons of carbon dioxide equivalent (C02e) increase in the last four years. To address this concern, stringent low U-value targets have been implemented, aiming to discourage the utilisation of fossil fuels. With the increasing construction of new dwellings, there’s an emphasis on achieving the mandated U-value standards. However, this emphasis on meeting U values has resulted in the overshadowing of considerations regarding embodied carbon.
This study investigated the potential of an automated BIM workflow that enables designers to visualise and mitigate the environmental impact of material selection within domestic construction projects in Ireland. The research aimed to create a BIM workflow that automates embodied carbon calculations throughout the modelling phase, embedding data from Environmental Product Declarations (EPD) into materials within Revit and visualising the impact using the created interactive dashboard. The research suggests that visualising the materials within a project benefits decision making when identifying the problematic area. The promotion of holistic approaches is necessary with the dynamic nature of new sustainable construction methods.
The study initially carried out an in-depth literature review to identify gaps in existing BIM based methods. To test the created BIM workflow, a case study was chosen. Through comprehensive data mapping and the use of the created interactive visualisation dashboard, problematic areas in material selection were identified, allowing for informed
substitutions that significantly reduced the building’s carbon footprint, illustrating the potential of such methodologies in achieving sustainable construction goals. It is evident from the existing literature that steps towards BIM integration of LCA and GWP visualisation are required to support the decarbonisation of the built environment. The process for conducting this case study research will be structured into key stages as outlined below:
- Identify benchmarks and prepare validated and unvalidated data sources to be used in study.Create a digital material library for Revit and map GWP data to materials through the development of a visual programming script.
- Model case study digital building for experimentation of the study.
- Create an interactive dashboard to visualise the whole-life global warming potential of materials within the project.
Various methods were explored to integrate GWP data into materials within Revit. The first step to creating a material library was identifying where the data was being inputted; this was achieved by creating a suite of shared parameters housed in the materials. After analysing the existing methods, a single dataset was chosen: a manually inputted Excel dataset where the author inputs both ICE and EPD/DoPC data structured in the template. It allows for materials to be created and mapped with GWP data instantly, once instead of multiple times per EPD/DoPC, as demonstrated by Dempsey & Mathews (2023), the material name is identified by the user, and density and all stages of GWP are inputted. A dynamo script was built to input materials into the dataset while mapping materials to the shared parameters housed within the material parameters. When the script is played, the materials outlined in the dataset are created with their associated GWP values. The digital model is then built using the imported materials, the materials automatically populating a pre-built material take-off schedule. This then allows for automatic calculations of GWP of the building. The schedule is subsequently employed to compute a cumulative total.
As projects progress, the schedule will update automatically. In the preliminary stages of a design where specific materials are not known, the ICE database materials are generic and not manufacturer products. It should be noted that this can cause inaccurate calculations with unvalidated data. As researched, the main problem with calculating the GWP of a design is identifying where the problematic area is. A visualisation dashboard was created in power BI. When the file is loaded, a series of pre-built data visuals in Power BI will automatically populate, including an interactive representation of the BIM model with associated GWP data within the project. The tool has an interactive dashboard which identifies the building’s overall kgC02e, its comparison per m2 to the RIAI 2030 targets, and individual materials kgC02e. The tool can create multiple versions for comparison, in effect ‘optioneering’ the material selection.
To test this workflow further, a focus group was approached. Built environment professionals tested the workflow on real world projects to gauge its practicality and to ultimately find out whether it promoted decision making in material selection. The analysis of the focus group showed a number of key findings that the workflow played within the built environment. It was shown that 60% of participants made better material decisions due to visualising the impact.
Judges' comments
The Judges were unanimous in agreeing that Killian’s report was both an engaging read and addressed a subject that is a real issue for all designers and an important topic for the Architectural Technologist and the broader built environment.
With bang up to date references and a clear method, this study addresses early design embodied carbon in a meaningful way. The Judges were impressed with the clarity of the literature review and the practical approach. This well considered and executed piece of work was imaginative and highly effective in highlighting the importance of visualisation tools in addressing embodied carbon in the early design stages. With its mix of text, diagrams and graphs combining to make it an effectively written and informative piece of work.
The Judges all commented that the work was innovative in its approach. They also recognised the considerable effort that had gone into the research. They praised the work for its systematic nature and seemless progression, from the introduction, highlighting the importance of the topic, through to the clear analysis and insightful conclusions.
This is an outstanding contribution to the subject. Killian has an excellent writing style; the work was a pleasure to read, and he should be proud of his contribution to the subject and in providing us this exemplar.