The Chartered Institute of Building (CIOB) held a roundtable discussion with the Chartered Institution of Highways and Transportation (CIHT) in January 2026 to explore how clients and their delivery partners can work more effectively together to decarbonise the UK’s road network. 

Participants ranged from strategic road authority representatives to local authority practitioners and contractors delivering work for both strategic and local networks.

With a welcome from CIHT’s CEO Sue Percy and chaired by Phill Beaumont, of Premier Traffic Management, the consensus was clear. There is real momentum on technical solutions, but progress is constrained by the same structural issues that have long shaped highways delivery: ageing assets, short funding horizons, policy uncertainty, risk aversion, and skills shortages.

The meeting was conducted online under the Chatham House rule to encourage honesty and open debate. Delegates’ identities have been kept confidential. What follows is a synthesis of the main messages for CIHT and CIOB members. 

Existing technological solutions are constrained by the underlying delivery context 

Participants agreed that many practical decarbonisation measures are already available, but difficult to mainstream under current delivery conditions.

The reality of ageing assets remains an overwhelming challenge. A strategic road authority representative described how the road network in Wales is dominated by maintenance and upgrades managed through trunk road agents and external contractors. When it came to decarbonisation, she said, legacy materials and construction forms are not always compatible with new approaches, making it harder to shift to business-as-usual low-carbon solutions. Another strategic road authority representative agreed: decarbonising materials and plant is only one part of the problem; the scale and condition of existing assets is a major constraint.

Climate adaptation was repeatedly raised as amplifying both risk and cost. A strategic road authority representative offered a stark example from National Highways: much of the drainage infrastructure is built to old standards and replacing it wholesale is simply not feasible. This was framed as a fundamental restriction on how far traditional engineering responses can take the sector. In response, National Highways are increasingly considering smarter maintenance strategies and alternatives such as nature-based solutions to pursue their decarbonisation and resilience goals.

Funding horizons are critical for decarbonisation

A pervasive theme was that decarbonisation is thwarted by short-term funding cycles and policy uncertainty. A tier-one contractor reported that although many carbon-reducing options are available, they come with an upfront cost uplift that is difficult to justify in current economic conditions. 

A local authority representative made the strategic point that without long-term planning, finance and pipelines, decarbonisation remains episodic rather than systemic.

Several participants framed long-term funding as the key that allows clients to shift from reactive patching to preventative, lower-carbon asset management. A strategic road authority representative described the Welsh Government’s move away from year-by-year allocation towards a longer-term approach, arguing that the longer the horizon, the more feasible it becomes to plan and take preventative action.

Another strategic road authority representative noted the destabilising effect of interim funding settlements on National Highways, and the importance of a new Road Investment Strategy for planning, investment and supply chain confidence. She noted, though, that until low-carbon options are at least cost-neutral, they will remain difficult to accept.

Overall, participants were explicit that uncertainty slows delivery and damages the market’s ability to invest in low-carbon capability. If government wants the supply chain to invest in plant, processes and lower-carbon materials at scale, it needs to provide the conditions that make such investment rational. 

Standards and risk aversion are a barrier to progress

The sector’s aversion to risk was cited across client and contractor perspectives as an important barrier. A tier-one contractor argued that the traditional approach – long trials, slow adoption – is structurally misaligned with net zero timescales. A strategic road authority representative summed up the cultural challenge: “The phrase, ‘But we’ve always done it like that’ needs to be banished!”

Standards were discussed as both a barrier and opportunity. A strategic road authority representative mentioned that the significant updates to the Design Manual for Roads and Bridges (DMRB) actively removed barriers to innovation. She highlighted the work that National Highways has done to communicate what is now allowed in low-carbon materials and methods. Her implication was clear: standards are often blamed for inaction, but sometimes the sector simply has not internalised and implemented the updates.

A representative from a devolved administration added a useful contrast. He explained that, as a one-stop shop for trunk and local roads, the Department for Infrastructure in Northern Ireland should find coordination easier than the equivalent authorities in Great Britain. Citing tier-one contractors’ (who are often also suppliers) fast growing warm mix capability, he highlighted the department’s inability to capitalise on the decarbonisation potential because their procurement systems and specifications had not kept pace. 

It’s clear that decarbonisation needs clearer routes through standards and assurance, so that decision-makers can adopt low-carbon alternatives confidently and consistently.

PAS 2080 is emerging as a common operating system

PAS 2080:2023 Carbon Management in Infrastructure featured repeatedly as the unifying framework that can give consistency of language, data and expectations across projects and organisations. A strategic road authority representative said that a significant majority of National Highways’ supply chain is PAS 2080-certified and that it helps embed consistent behaviours and reduce greenwashing. A devolved administration representative described plans to embed PAS 2080 in contracts and business cases in Northern Ireland through an infrastructure sector plan, alongside changes to specifications and adoption of warm mix and other products.

However, there was broad agreement that the application of PAS 2080 has to be proportionate, even where support for its underlying principles was strong. A strategic road authority representative noted that the Welsh Government’s policy emphasis on supporting local economies – including smaller local contractors – meant that the Strategic Road Network in Wales cannot simply mandate certification across the board. 

A strategic road authority representative described how National Highways were planning to overcome this issue: suppliers above a certain threshold must have PAS 2080 certification; below it, however, they can still bid without certification so long they can evidence compliance with the PAS’s “binding principles”. A tier-one contractor echoed the point, suggesting that where PAS certification is unrealistic for small suppliers, clients and tier ones can still require working “in accordance with” PAS 2080, using it as a shared reference point for expectations and challenge. Both approaches avoid excluding micro-businesses while still rewarding decarbonising behaviours across the ecosystem.

The policy implication is straightforward: if PAS 2080 uptake is growing, government can accelerate coherence by aligning guidance, reporting expectations and funding conditions – without necessarily mandating certification in a way that disadvantages smaller firms.

Skills retention is critical

A local authority representative highlighted the critical importance of skills and knowledge continuity to carry through strategic change. He cited the example of Lancashire County Council’s award-winning decarbonisation strategy; when key expertise left the organisation it could be difficult to keep the momentum going. The implication was that decarbonisation strategies can remain highly dependent on heroic individuals but need to be embedded as organisational systems if they are to be delivered. There can also be internal cultural issues, with some teams considering low-carbon materials late, bolting them on rather than designing for whole-life carbon.

Other participants echoed the knowledge gap more broadly. Many people in highways delivery are still unclear whether net zero refers to construction, operation, or system outcomes. They saw professional institutions as part of the answer – particularly in setting common expectations, normalising good practice, and reducing unnecessary duplication. In response, Justin Ward, of CIHT, noted CIHT already expects members to focus some of their CPD on transport decarbonisation, which directly aligns with the roundtable’s emphasis on standardised training and shared understanding.

Amanda Williams, of CIOB, reported that similarly, CIOB have embedded environmental sustainability as a mandatory professional review core theme in its CPD Policy.

Data, measurement and ‘single source of truth’ issues remain unresolved

A local authority representative pointed out that, based on carbon accounting evidence, tackling materials may not be where the largest carbon savings are to be had. This directly challenges a common assumption in the sector and reinforces the need for whole-system carbon literacy, rather than defaulting to material substitution alone. 

He argued further that the sector still lacks consistent ways to measure whole-system outcomes. It can measure the carbon of constructing an intervention but struggles to represent future system impacts (for example, the modal shift effect of adding a bus lane). Several participants raised concerns about greenwashing and inconsistent tools. 

The consensus felt that measurement is possible, but that inconsistent measurement undermines confidence, adoption and procurement fairness.

A linked point is that funders can influence measurement maturity. A local authority representative described how some teams might only engage with carbon when they need a carbon management plan to access DfT funding. That suggests that funding conditions can drive behaviour, but they need to be consistent and supported with practical guidance.

Reframing ‘net zero’ as ‘efficiency’ and emphasizing co-benefits

Several participants noted that the term ‘net zero’ is becoming politically contentious in some settings. A local authority representative reported that some local authorities are not allowed to use the term. Several participants found that substituting ‘net zero’ with ‘efficiency’, ‘longevity’ or ‘resilience’ was more palatable and kept decarbonisation on the agenda. 

Participants approached this “political shift” as an operational reality. A strategic road authority representative described linking decarbonisation to things citizens value: smoother rides, reduced noise, and longer-lasting pavements. Amanda Williams, of CIOB, reinforced the point: co-benefits for people and communities matter in the narrative.

The implication is that the sector can keep moving even when the label changes – but only if government policy remains stable.

Opportunities: digital, AI, and engineering out waste

Participants were optimistic about digital opportunities. A couple saw AI as a major efficiency driver, provided the sector establishes sensible assurance and legal defensibility. 

A strategic road authority representative offered a concrete example of the potential: a camera vehicle and AI training produced the most comprehensive streetlighting dataset National Highways has, in a fraction of the time required by historic spreadsheet-based approaches. The next logical step, she suggested, is to treat routine network driving by traffic officers and asset vehicles as an opportunity to capture data.

A local authority representative saw the potential for digital and AI to eliminate wasteful inspection and intervention cycles, using sensors and data to target works, reduce failure and reduce emissions from repeat visits. The “utopian” vision is that better low-carbon delivery could go hand in hand with better customer outcomes and lower costs.

Too little collaboration; too much duplication

A recurring frustration was that the sector is spending money and time reinventing the wheel. A local authority representative highlighted the absurdity of multiple local authorities running similar trials independently rather than learning from each other. Not only is the current process expensive, but the industry is slow to adopt new practices and materials.

A tier-one contractor observed that contractors often guard innovation as a commercial advantage in bids. If sharing is to improve, procurement must reward openness rather than secrecy, turning collaboration from an aspiration into commercial reality. 

Participants acknowledged various efforts to overcome this situation, including the LiveLabs 2 programme and National Highways’ carbon hub and open sharing of tools and registers, but feared they weren’t sufficient. In particular, a local authority representative noted the risk that LiveLabs 2’s legacy could be lost when it ends if learning is not disseminated and embedded.

Several participants proposed practical coordination mechanisms: central repositories for results, requirements to upload case studies, and use of large sector events (such as the annual Highways UK conference) to coordinate “who leads on what” across clients, contractors and institutions.

The key message is that fragmented learning is expensive. A relatively small amount of ringfenced funding for trials, coupled with mandatory dissemination and common reporting formats, could unlock disproportionate value.

Summing it all up

Generally, there was broad consensus on what would accelerate progress:

1. Long-term funding clarity and pipeline certainty to support preventative maintenance and supply chain investment.
2. Consistent policy direction and standards clarity, so carbon is not a bolt-on that is traded away under pressure.
3. PAS 2080 as the shared operating framework, applied proportionately to include SMEs.
4. Standardised training and capability building, supported by institutions such as CIHT and CIOB, to reduce knowledge loss and inconsistency.
5. A step-change in collaboration, with incentives to share evidence and avoid duplicated trials.

If carbon reduction continues to be treated as an add-on, strategies will continue to be eroded by value engineering, programme constraints and procurement pressures – precisely because it is not yet embedded as a delivery requirement. As several participants made clear, carbon has to become core policy, encoded through standards, tenders and contracts, and supported by government direction.

The roundtable’s overall judgement was therefore cautiously optimistic. The tools, technologies and examples exist, and the sector is learning fast. The remaining challenge is how to create the stable governance, funding and collaboration environment in which decarbonisation at scale is normal.

Our thanks to the Chair, Phil Beaumont, Business Excellence Manager for Premier Traffic Management, and to the CIHT roundtable participants.