Reducing Embodied Carbon in Ventilation Systems: A Critical Step Toward Net Zero

As the built environment accelerates its transition toward net zero, the industry’s attention has rightly shifted from just operational efficiency to whole-life carbon emissions. While energy efficiency remains crucial, reducing embodied carbon—the emissions associated with the production, transportation, installation, and disposal of building materials—has become an urgent priority. Among these materials, mechanical, electrical, and plumbing (MEP) systems are estimated to account for around 23% of a building’s embodied carbon. As developers, specifiers, and manufacturers align with Science-Based Targets and upcoming regulations, the HVAC industry faces a clear mandate: reduce embodied carbon without compromising performance, reliability, or indoor air quality.

Embodied Carbon: The Overlooked Culprit

Traditionally, much of the building industry’s focus has been on operational carbon—the emissions generated during the use phase of buildings. However, embodied carbon can account for 20-50% of the total lifecycle emissions of a building, depending on usage type and design. As operational carbon is reduced through improvements in building efficiency and renewable energy adoption, the relative impact of embodied emissions becomes even more significant.

For ventilation systems, this challenge is particularly nuanced. These products are essential for indoor air quality, thermal comfort, and regulatory compliance. Their complexity, the materials used (primarily steel and plastics), and the necessity for durability make decarbonisation more difficult—but not impossible.

The Role of Material Innovation

Reducing embodied carbon in HVAC systems begins with material choices. Steel, a staple material in commercial ventilation units, is a major contributor to embodied carbon due to the energy-intensive processes involved in its production. Similarly, plastics used in residential systems and ducting often rely on virgin fossil-based polymers.

Progress is being made. One promising development is the transition to low carbon-emissions steel made using recycled content and renewable energy sources. Recycled and renewably produced steel, such as XCarb® from ArcelorMittal, dramatically lowers the carbon footprint of HVAC components. For context, this steel has an embodied carbon footprint of just 0.898 tCO₂e per tonne, compared to 2.51 tCO₂e for conventional steel.

Nuaire is the first UK ventilation manufacturer to switch to this innovative steel across several high-volume commercial products, including our BPS air handling units and XBOXER XBC packaged heat recovery systems. This shift will result in a 64% reduction on the steel proportion of our SCOPE 3 embodied carbon activity within the first year alone, compared with the same steel manufactured via the conventional steelmaking route.

Plastics present another opportunity for carbon savings. The casing material in our Drimaster-Eco Positive Input Ventilation (PIV) units was recently switched from virgin ABS plastic to 100% recycled plastic, reducing carbon by 167 tonnes each year. The only noticeable change for customers is a shift in the product’s external colour—from blue to black—highlighting that sustainable change needn’t sacrifice function or form.  We have also changed to recycled plastic for our ducting, and implemented careful material reduction and other material substitution, which removed 2,000 tons of carbon from our product portfolio in 2024 alone.

Measurement, Transparency, and Accountability

Reducing embodied carbon is not only about making better material choices – it also requires transparency and standardisation in measurement. Without consistent, verifiable data, designers and clients struggle to assess and compare options across product categories.

To support this need, manufacturers need provide CIBSE TM65-compliant embodied carbon assessments, which estimate the emissions associated with HVAC products from raw material extraction to end-of-life. These datasheets allow specifiers to make informed decisions, balancing carbon performance with cost, efficiency, and compliance requirements.

Nuaire, as part of our broader carbon strategy, now provides TM65 datasheets for the majority of our product range. This helps consultants and developers incorporate embodied carbon metrics into Building Information Modelling (BIM) and lifecycle assessments, offering clarity and comparability that have long been missing from HVAC procurement decisions.

Scaling Impact Through Collaboration

Transformative change doesn’t happen in isolation. The HVAC sector’s decarbonisation journey will require deep collaboration across the supply chain. Nuaire’s partnership with Steelco, a UK steel supplier, and ArcelorMittal is a case in point. These long-term relationships enabled the early adoption of XCarb® steel and demonstrate how joint innovation between manufacturers and material suppliers can fast-track progress.

It also reflects a growing understanding that supply chain emissions (Scope 3) are where many companies must now concentrate their efforts. By working closely with suppliers to validate Environmental Product Declarations (EPDs), manufacturers can help drive broader systemic change across the industry.

From Leadership to Industry Standard

As regulatory pressure grows—such as potential embodied carbon caps and whole-life carbon assessments becoming mandatory in future UK building regulations—early adopters will set the standard for the rest of the market.

However, beyond compliance, there is a broader imperative. The climate crisis demands more than incremental change. By tackling embodied carbon in ventilation systems, the HVAC sector has a real opportunity to lead by example—delivering healthier buildings that don’t cost the earth.

Conclusion: A New Carbon Paradigm

The road to net zero is not a straight one, and it certainly doesn’t end with energy efficiency alone. Reducing embodied carbon in ventilation systems is both a technical and ethical challenge—one that calls for innovation, transparency, and industry-wide commitment.

Material innovation, such as the adoption of low-carbon steel and recycled plastics, is a crucial first step. So too is the development of measurement frameworks like TM65, which allow decision-makers to prioritise carbon performance alongside traditional criteria.

As more manufacturers more toward low-carbon products, and as demand from developers, architects, and occupants continues to grow, the ventilation systems of tomorrow will be defined not only by how efficiently they move air—but by how responsibly they are made.

Nuaire has been delivering clean air solutions for over 50 years, setting industry standards in residential, commercial and industrial ventilation systems.  For more information go to www.nuaire.co.uk