Carbon Expert of the Month March 2020

Q: What led you to become a construction carbon expert?

I have been fascinated by materials from my earliest days as a student of architecture and engineering. I began to fully grasp the connection between materials, and human and planetary health when I worked for the architecture practice McLennan Design in Seattle on a Living Building Challenge residential project. I was in charge of the materials aspect to ensure healthy and environmentally friendly products based on full transparency of ingredients.

When I joined Integral Group, a global deep green engineering practice, I turned my focus to the materials used in building services and started to investigate their environmental impacts through LCA. Until now engineers have concentrated on reducing operational carbon footprint, with little attention paid to embodied carbon part and other environmental impacts. This needs to change. I believe lifecycle thinking should be fully integrated within our design process both for Engineering and Architecture.

In a high impact scenario, refrigerant accounts for a large proportion of a whole building’s embodied carbon emissions
Source: CIBSE

Onsite electricity generation by PVs offset the building’s operational carbon but not all its embodied carbon emissions
Source: CIBSE

Q: What kind of projects do you typically work on, and in what role?

My role at Integral Group is to lead the development of our global LCA practice. I support colleagues involved in LCA work across North America, Australia, and Europe to advise architects and clients on materials selection to achieve project goals. However, my primary responsibility is to lead our research and development of LCA for building services and their contribution to the performance of the building as a whole.

Our LCA research program is wide-ranging. We are evaluating individual products and developing tools to help engineers compare strategic choices of systems for heating, ventilation, lighting, and cooling at the earliest stages of design. We are also developing new ways of integrating LCA into our design workflow and digital engineering processes.

Q: What project and achievements are you the proudest of?

In November 2019 CIBSE Journal published our case study on whole-life carbon for a deep green retrofit project in California. We wanted to understand the whole life carbon emissions from mechanical, electrical and plumbing (MEP) services compared to the rest of the building’s carbon emissions.

We found that building services, in the worst impact scenario, could be responsible for approximately 50% of embodied carbon emissions, which could be drastically reduced in the best impact scenario to 15%. This shows building services must not be ignored or ‘guesstimated’ when conducting LCA to mitigate environmental impacts. Refrigerant leakage alone was accounting for 20% of all building embodied carbon emissions (worst impact scenario) – as a result, we are currently doing research and building knowledge in our different regions about refrigerant best practice to minimize global warming impacts.

Q: How does One Click LCA help you achieve your goals?

We use One Click LCA in a very different way than for standard project LCA – we particularly use it for its database and the settings it offers. The article in CIBSE Journal details the methodology we used for our Office Fit Out study – it is a good example of how we use One Click LCA in our research.

Q: What do you find most useful in One Click LCA?

I have looked at different tools, but what I found interesting about One Click LCA were its database and its flexibility. Globally, there is limited data and information on the embodied carbon emissions of MEP equipment. One Click LCA provides some good data in this area, although there is a lot of scope for this to grow. Consistency of LCA methodology, assumptions and calculations are important – One Click LCA enables you to choose the right setting depending on the purpose and location. For instance, for each project, one can decide to select CML or TRACI, adapt to different certifications definitions. Features such as these are crucial if we want to compare “apples to apples”.

Q: What are the key value drivers you use to make the business case for materials carbon?

Our clients all know that buildings produce a huge amount of greenhouses gas emissions across their life cycle. What they often don’t realize is that we have solutions that can solve this problem today, and the expertise to build better.

Groups like the London Energy Transformation Initiative are helping everyone to make the business case by providing clear and simple guidance to the design and construction industry, breaking down the barriers to action.

I was happy to contribute to the Embodied Carbon chapter of LETI’s Climate Emergency Design Guide and their Embodied Carbon Primer, published early this year. As knowledge of what can be achieved grows and spreads, our ability to take positive action increases exponentially.

Q: How does your engagement on materials sustainability vary over project phases?

My current focus is before design has begun! Our research is identifying the ‘hot spots’ and looking at how to avoid them or mitigate their impact so that design teams can work through subsequent design phases, during construction, and facility management to deliver projects that are optimizing performance rather than trying to fix mistakes.