Building a net-zero future: Why early engineering is more critical than ever

The UK’s race to net-zero is reshaping the construction industry, elevating the structural and civil engineer’s role in the early design stages to a critical new level. At Perega, we are seeing that the focus is now moving beyond a building’s operational efficiency to the carbon embedded in its very DNA.

Beyond operational carbon

While efforts have successfully driven down operational carbon, a new challenge has emerged: embodied carbon.

Operational carbon is released over the building’s 50+ year life. Our job is to design structures that seamlessly integrate renewable energy systems like solar panels and ASHPs, ensuring these solutions are structurally sound from day one.

Embodied carbon, on the other hand, is primarily released upfront during construction, the energy used in manufacturing, delivery, and installation. Since emissions before 2050 are the most critical, reducing upfront embodied carbon is now vital.

With new, efficient buildings, embodied carbon can account for roughly half of a project’s total emissions. Crucially, structural engineers have the most control over this factor, making our early involvement in projects highly advantageous to clients.

Anticipating policy and driving innovation

We anticipate the UK Net Zero Carbon Buildings Standard could soon become a regulatory requirement, setting firm targets for both carbon types. Perega is already prepared; our in-house Net Zero Carbon group monitors policy shifts and ensures all engineers are proficient in carbon assessments.

Our single most important piece of advice to clients is to engage with us early. Providing the scope and time for carbon option appraisals at the preliminary stages is the most effective way to secure a net-zero outcome. Allowing time early in the process ensures that a client’s carbon goals can be aligned with key project drivers, often reducing overall costs when low-carbon strategies are considered from the outset.

Tools for the circular economy

To minimise embodied carbon, we champion innovation and circular economy principles. While we rely on digital calculators to assess and compare structural options throughout the design stages, we recognise that the most significant carbon saving comes from re-using existing buildings first. In terms of material choice, we advocate for low-carbon options like traditional and engineered timber (CLT/Glulam) and actively promote the reuse of structural elements, including steelwork, leveraging protocols to recertify reclaimed materials.

When integrating renewable energy systems like solar panels, we would propose carrying out carbon calculations to ensure the embodied carbon required for their installation is not greater than the operational carbon savings.

Design for a second life

The future of engineering is about designing for disassembly, creating buildings whose components are seen as valuable resources for the future. In practical terms, this means favouring mechanical, reversible connections such as bolts and screws over welding. This allows materials to be non-destructively recovered and reused at the end of a building’s life.

We can also design for easy access to these connections and promote the use of standardised grid sizes, which ensures components have consistent dimensions and can be easily integrated into a future structure. While full disassembly isn’t possible for reinforced concrete buildings, the focus shifts to re-using and strengthening the existing structure, which is far more carbon-efficient than demolition.

Our ultimate goal is to ensure every structural engineer has the opportunity to make net-zero a primary project consideration, proving that lower-carbon construction simply means smarter engineering.

By Charles Rothnie, Senior Structural Engineer, Perega