EPDs, embodied carbon and the need for clarity
Darren Fereday, Area Sales Manager, Midlands, for IV Produkt, explains why reliable, third-party-verified EPD data is essential in a UK market where many ‘EPDs’ are inconsistent or self-declared.
Designers and consultants across the UK are being asked to make more environmental judgements than ever before. Decisions that were once driven primarily by performance, space and cost now sit alongside questions of embodied carbon, whole-life impact and long-term sustainability. Environmental Product Declarations (EPDs) are intended to help. In theory, they give designers confidence that products have been assessed properly and that environmental claims are based on evidence rather than assumption. In practice, many in the industry are finding the opposite. Instead of clarity, there is growing uncertainty about what an EPD really represents!
When everything is an EPD, nothing really is
In the current UK HVAC market, designers are presented with a wide mix of environmental information. Alongside third-party-verified EPDs based on ISO standards, there are ‘company’ internal carbon calculations, simplified spreadsheets and different interpretations of guidance such as CIBSE TM65. All of these can be useful in the right context, but they are fundamentally different in scope, robustness and intent.
The issue is not that these different approaches exist. The issue is that they are increasingly presented as an equivalent. When environmental data is produced using different system boundaries, different life cycle stages or different assumptions, comparison quickly becomes unreliable. Two products can appear similar on paper while being assessed in completely different ways. For consultants trying to make defensible decisions, that creates real risk. Embodied carbon has become too important, commercially, technically and politically, for this level of ambiguity to continue.
What sits behind a credible EPD
A proper EPD is not just a summary document or a single carbon figure. It is the final output of a defined process built around a full life cycle assessment (LCA). That assessment considers environmental impact from raw material extraction and manufacturing to a product’s end-of-life and material recycling. Crucially, the LCA must also be accompanied by product-specific category rules (PCR). These PCRs exist to remove interpretation and ensure that similar products are assessed in the same way, using the same assumptions and boundaries.
Once completed, the EPD is independently verified and published by an accredited Programme Operator, such as EPD-Global or equal, and officially published on a public platform like the ECO-Platform or similar. This makes the data transparent, reviewable and comparable. Without that external verification, it becomes very difficult to separate robust environmental assessment from optimistic estimation. As Scope 3 emissions move firmly into focus, that distinction matters more than ever.
The industry has made genuine progress on operational energy efficiency. Modern air handling units (AHUs) are, for example, significantly more energy efficient than they were a decade ago, and that progress should not be underestimated. But as operational energy and carbon reduce, embodied carbon takes on greater importance, and this is where HVAC systems often become far more complex than they first appear.
Traditional AHU installations typically depend on large external heating and cooling systems. Boilers, chillers, heat exchangers, pumps, valves and extensive pipework bring significant quantities of steel, copper, aluminium and other construction materials into a building. All this material carries embodied carbon before the system has even been switched on. When assessments focus on individual products rather than the system, these impacts are easily underestimated.
Doing less, rather than adding more
In addition to the use of energy efficient products, one of the most cost effective ways to reduce the environmental impact of an HVAC system is to downsize and simplify the system itself. Integrated air handling solutions, where DX heating and cooling are built directly into the AHU, significantly reduce the need for external plant and extensive distribution networks. The ThermoCooler HP concept from IV Produkt is one such example, combining ventilation, heating and cooling in a single packaged unit.
The operational benefits are well understood. Reversible heat pump AHUs can reduce energy use in ventilation applications with variable heating and cooling demand. What is often overlooked is the impact on embodied carbon. Fewer components mean less material. Less pipework means less steel and copper. Smaller plant rooms reduce structural demand. Taken together, all these reductions can have a substantial effect on the overall HVAC system EPD.
At some point, improving individual components can even deliver diminishing returns. Real progress comes from stepping back and asking how the system can be made simpler, lighter and more efficient. That shift in thinking changes the conversation. The question becomes not just how an AHU performs energy wise, but what its selection enables or avoids elsewhere in the building.
When whole-system decisions are supported by independently verified EPD data, embodied carbon becomes something that can be actively managed rather than retrospectively estimated.
A more dependable way forward
If the industry is serious about decarbonisation, expectations around environmental data must rise with it. Designers and consultants should be comfortable asking where EPD data comes from, how it has been verified and whether it is publicly available or not.
Favouring independently certified EPDs is not about limiting choice. It is about restoring confidence in the data that underpins critical design decisions. At IV Produkt, all products are supported by third-party-verified EPDs produced in accordance with ISO and PCR international standards. That approach reflects a belief that transparency and consistency are essential if sustainability is to move beyond intention and into delivery.
Decarbonising HVAC will not be achieved through isolated product choices alone. It requires better data, simpler systems and a willingness to look beyond traditional design assumptions. Independently verified EPDs and more integrated HVAC solutions provide a clearer, more dependable foundation for that shift. By insisting on transparency and designing systems that achieve more with less material, the industry can make real progress towards lower carbon buildings, grounded in evidence rather than interpretation.
Breaking down the savings
The energy savings between a traditional 4.0m3/s AHU HVAC design for heating and cooling and an equally sized ThermoCooler HP is approximately 20%, or 6,500kWh/year for Greater London with an annual average temp of 10°C and 3,000 running hours.
By using the UK SAP 10.2 values of 0.241kg CO2e/kWh for LPG heating and 0.136kg CO2e/kWh for standard electricity, the ThermoCooler HP solution provides an annual CO2e reduction of 2,100kg, equal to an operational decarbonisation of 37% per year.
Figure 1: Graph demonstrating how the ThermoCooler HP reduces CO2eq emissions by up to 37% in a typical Greater London scenario. Note – The energy source for the traditional AHU HVAC design is gas compared with electricity for the ThermoCooler HP.
When comparing the total embodied carbon, EPD, of 19,300kg CO2eq for the traditional installation with the 9,300kg CO2eq for the AHU integrated reversible heat pump installation, an even larger saving of 10,000kg CO2eq equal to 52% emerges.
Figure 2: Embodied CO2eq reduction between a traditional AHU HVAC design and an AHU with integrated heat pump design.
