Designing for Carbon with Ren DeCherney
1/ What are the most common mistakes even experienced design teams make when it comes to carbon neutral ambitions?
The most common mistake is thinking you need to get everything right from day one. The numbers can look overwhelming, and I know this is a public forum that will end up on YouTube, but I will admit something. I still cannot read an EPD. They scare me, and as a designer I had no idea where to begin. So I did nothing, which never helps. The real mistake is believing you cannot take action. Ask manufacturers if they have reduced embodied carbon. If they say yes, great. Ask them which targets they have reached. Then ask about their circular approach and how you can work together when the product reaches the end of its first life.
2/ Where can we find the scorecards on the digital platform?
You can explore the C2C digital platform on our website. Go to c2ccertified.org and look for the button at the top that says “certified products”. That section gives you access to the platform. Right now there is a beta version of the new visual scorecard available. The full and more detailed version will go live in January.
3/ How can carbon targets shape creative choices while still preserving design freedom?
There are now many sustainable options for designers, so carbon targets no longer limit creativity. Manufacturers are meeting reduction goals and offering takeback programs, giving you plenty of choice. Designing with recycled or circular materials simply requires a different mindset. You do not always know exactly what you will start with, but many designers see this as an exciting creative challenge. We are hired to deliver thoughtful solutions and we can adapt. If we could move from AutoCAD to Revit, we can adapt to circular design too. There are many verified low carbon products available, often at the same price.
4/ Do you feel that designers take all dimensions of sustainability into account when selecting a product, or are there certain aspects that are often overlooked?
I always tell designers that they do not need to tackle every aspect of sustainability at the same time. Choose one area you truly care about and focus on that. When you are passionate about a topic you naturally return to it every day. If you use a strong multi attribute certification, it will cover the other sustainability dimensions for you. For example, I focused on material health, but by working with Cradle to Cradle Certified products I was also supporting circularity, ecosystem health and social fairness. So my advice is simple. Find the aspect of sustainability that feels most authentic to you. When you care about it, you can explain it with confidence to clients and you will want to keep improving. You do not need to do everything at once. Pick one meaningful starting point and build from there.
Designing with Data with Sunita Van Heers
1/ What information do clients need, to understand the real impact of their material choices?
Clients need clarity on why their choices matter. Regulation is a key driver. Reducing environmental and carbon impact will become mandatory. The rules are already approved at the European level and countries will roll them out in their own timing. They also need to see that material choices can create real value. Operational carbon has already been optimised, so the biggest impact now often comes from materials. Reusing flooring, for example, can equal many years of energy consumption. This helps clients understand how much carbon is embedded in materials and how much they can save. Finally, clients often assume that reuse or circular solutions cost more. This is not always true. Costs depend on the building. Some parts are expensive to dismantle, others are not. When a solution does not increase costs and clearly reduces carbon impact, it becomes the logical choice.
2/ The slides mention that reusing the carpet saves 13 years of operational carbon impact. Is this the operational impact of the flooring or of the entire building?
It refers to the operational carbon impact of the entire building. The example came from an office building where operational carbon covers energy and water use. The building was already well optimised, so its operational impact was relatively low. In this case, the carbon savings from reusing the carpet equalled about thirteen years of the building’s operational carbon. For a more energy intensive building the comparison would look different. The calculation always depends on the specific project.
3/ What are the biggest data gaps today that hinder reliable circularity assessments in construction or real estate?
Circularity covers many aspects. It includes the depletion of raw materials, but also dismantling potential and flexibility. There is no single calculation that captures all of this. Tools like the Circularity Value Indicator focus on the financial value or residual value of reuse rather than full circularity. One major gap is the quality and completeness of EPDs. Some EPDs are only partially filled in and many materials still have no EPD at all. As a result, databases often rely on generic averages that group very different materials together. More consistent EPDs, all calculated under the same European standards, would significantly improve reliability. Another gap lies in the understanding of circularity itself. People often expect one clear number, but circularity is more complex. A good example is wood. CLT stores carbon during its life, yet if the wood is burned the stored carbon is released again. You cannot claim a carbon neutral or carbon negative building unless you are certain that the wood will not be burned. This type of complexity still needs broader awareness and better data.
Closing the Carbon Gap with Ella Smith
1/ To what extent is the availability of material data a concern and how does trust in that data play a role?
The data set is still evolving. Since we released the research two years ago, the situation has already improved quite a bit. For design teams the most important step is to request EPDs from manufacturers and suppliers because these documents outline the carbon and biodiversity impacts of each material. Even when a manufacturer has not yet produced an EPD, the act of requesting it encourages them to start the process. It is a time consuming task, yet it motivates many companies to expand their documentation, which in turn gives us more reliable data to work with. When a specific EPD is not available there are also industry standard carbon impact values. These are not linked to a particular product, yet they help us understand which material families carry the highest carbon load and where reductions would make the most sense.
2/ Why is it uncommon to collaborate with the tenant on their fit out and would sharing data from the original fit out with the tenant team make carbon reduction through circular design more scalable?
We rarely work directly with tenants because this is not our core focus. Our practice usually handles much larger projects, while tenants tend to engage designers who specialise in fit outs. This creates a structural gap between landlord led design and tenant led design. There is very little connection between the two stages, even when we know which tenants might eventually occupy the space. Establishing that link remains challenging. That said, there are delivery models that allow closer collaboration. On some projects the client team secures pre lets with major tenants. In those cases the tenant knows one or two years in advance that they will occupy the building. This gives us the chance to align the base build design with their future fit out needs. We can either collaborate with the tenant designers so they can develop both the CAT A and CAT B, or we design the CAT A in a way that supports whatever configuration the tenant will later bring into the space. Sharing data from the original fit out would indeed help scale carbon reduction, because it would give tenant teams a clearer starting point for circular strategies.
3/ Circularity and sustainability only become interesting for investors and developers when there is clear economic value. How can carbon reduction become financially attractive in commercial applications and which business models support this?
There is growing interest from investors who specifically seek low carbon performance in their portfolios. Tenants are also under pressure to meet ESG goals, which drives demand for certified and demonstrably sustainable office spaces. Not everyone is motivated by carbon reduction, yet the direction is shifting. The core principles are simple. We need to use fewer materials, choose options with lower energy intensity, keep them in place for longer and reuse as much as possible. In theory these steps should already deliver cost savings. Many business structures are not yet aligned with this logic, which makes implementation uneven. Even so the landscape is changing. Reuse is becoming the default approach on more projects and the financial argument is getting easier as manufacturers evolve their models from selling new products to refurbishing and recertifying existing ones. This transition supports lower capital expenditure, reduced waste and improved carbon performance. As for limitations in reusing components after strip out the constraints depend on the material. Warranty and insurance pose significant challenges. For instance with MEP equipment the warranty is void once the item is removed from the ceiling and someone must be willing to inspect it and take responsibility for its future performance. These barriers are real, yet they are not permanent. As more manufacturers recognise the market potential of refurbishment the process will become simpler. Design teams can accelerate this shift by continuing to push for reuse, request clarity and challenge standard practice. The fact that these conversations are happening more often is already a positive sign.
4/ How can a flooring manufacturer help lower the hidden carbon cost of fit outs and what role do product choices play in reducing waste across the full life cycle of a space?
A major contribution lies in understanding and communicating the carbon impact of each flooring option. This starts with obtaining EPDs for the different ranges offered. With clear documentation, manufacturers can identify which components or processes carry the highest carbon load and where improvements can be made. A cradle to cradle perspective is equally important. This means considering the entire life cycle of the flooring, including what happens when the product reaches the end of its useful life. If worn flooring can return to the supply chain and be used as input for new products, it supports higher recycled content, lower carbon intensity and reduced material waste. In other words, the loop stays closed because valuable resources continue to circulate rather than becoming waste. Maintaining channels to collect and process existing materials is a key part of that system. Many manufacturers already participate in recycling or take back schemes and continue to expand those efforts. Through thoughtful product choices and transparent data, flooring manufacturers can play a meaningful role in reducing hidden carbon impacts across the full life cycle of a space.
