黑洞社区

It is widely known that the construction industry ranks as one of the biggest contributors to the country鈥檚 carbon emissions; third after energy supply and transport. According to the UK Green 黑洞社区 Council, embodied carbon from the construction and refurbishment of buildings currently makes up 20% of UK built environment emissions. Within this, steel and carbon are the largest sources of CO2 emissions in the sector. The government has committed to achieving net zero by 2050. 

So, what does the industry need to do to address these challenges, and what might the Midlands鈥� route to net zero look like? To find answers to these questions, a roundtable discussion was held in Birmingham last month, hosted by 黑洞社区 the Future Think Tank and Constructing Excellence Midlands. Chaired by Ben Flatman, architect and editor of 黑洞社区 Design, the event gathered industry experts from engineers and architects to sustainability directors.

They spoke at length about the potential to use more timber in construction, the need for clearer environmental regulations, client buy-in around net zero, and improving the understanding of whole-lifecycle carbon in the sector.

The Midlands context

In 2021, the West Midlands Combined Authority (WMCA) introduced its first net zero five-year plan, aiming to cut emissions by 33% by 2026 and reach net zero by 2041.

Carl Rushton, head of sustainability at construction firm McLaughlin & Harvey, said that when he works on projects in London, where the target is to achieve net zero carbon by 2030, his company is required to produce material passports, which go beyond environmental product declarations.

Rushton noted that despite the West Midlands鈥� ambitious target, these kinds of rigorous standards have not yet been implemented. 

Rob King, director at architectural practice Howells, reiterated that the mayor of London鈥檚 development strategy, the London Plan, 鈥渋mpacts the buildings we design鈥� and helps to achieve sustainability goals. He added that when he worked on a scheme in Battersea, the planning committee had a rigorous design review panel process, drawing in sustainability and landscape experts to critique projects.

鈥淭hat framework doesn鈥檛 exist in the Midlands, and I think that would really help support councils,鈥� he said.

Danielle Michalska-Morris is group technical innovation manager at Barratt and David Wilson Homes Mercia division. Barratt opened a timber frame factory in Derby, East Midlands, in summer 2023. 

She pointed out the difficulties of working with various local authorities in the region, noting that they sometimes have inconsistent approaches. 鈥淎s a developer, it鈥檚 hard to make progress because one local authority might be aspirational and we鈥檝e got to do X,Y and Z and we invest in it, but we don鈥檛 have a consistent approach,鈥� she said.

David Kemp, director of sustainable communities at Turner & Townsend, said that devolved administrations such as the WMCA have the potential to accelerate progress towards net zero.

Kemp said that Part Z, a proposed amendment to the 黑洞社区 Regulations which would require developers to report on and reduce embodied carbon in their projects, would drive the industry forward. However, he noted that 鈥渆ven if Part Z lags behind, devolved powers have been granted to the mayoral combined authorities鈥�. He added that as with the example of the Greater London Authority, 鈥渢here is an aspiration to do more and go further and faster鈥�.

Embodied carbon and the need for more regulation

The roundtable discussion highlighted that while the built environment sector acknowledges it is a significant contributor to the UK鈥檚 carbon emissions, much of the focus remains on operational carbon, the emissions generated during a building鈥檚 use. However, panellists stressed that embodied and whole-life carbon, which covers emissions from the production of materials, construction processes and eventual disposal, are often overlooked despite their significant impact across a building鈥檚 entire lifecycle.

Kemp explained that whole life-carbon remains challenging for both domestic and non-domestic building owners and developers to address. He described it as 鈥渉ard to define鈥� and often 鈥渓ofty and opaque鈥�. Without clear references to embodied carbon in building regulations, he noted, the issue is frequently 鈥減ut in the too-hard-to-do pile鈥�.

Mike Bentham, an associate at Rider Levett Bucknall (RLB), reiterated this point, highlighting that 鈥渢here seems to be a knowledge gap among clients around the tradeoff associated between upfront carbon emissions and those from a whole-life carbon perspective鈥�. He added that conversations about operational carbon often occur in isolation from embodied carbon. 

Bentham highlighted the need for regulatory reform, referring to a proposed amendment in Part Z which would require embodied whole-life carbon assessments for any new building exceeding 1,000m虏  or containing 10 or more dwellings. He said this would make embodied carbon assessments a priority. 

Peter Blunt, managing director at Innovar茅 Offsite, also said a lack of regulation is hindering the industry鈥檚 progress toward net zero.

Blunt began his career in the car industry, which he said was more heavily regulated, before joining the construction sector 20 years ago: 鈥淚t still amazes me the lack of regulation and guidance there is in the built environment.鈥� In his view, when it comes to embodied and in-use carbon, 鈥渂ecause there鈥檚 no regulation, we won鈥檛 do it鈥�.

He said that Innovar茅, an offsite construction company with a factory based in Coventry, has built 鈥渁ll sorts of weird and wonderful stuff鈥� including Passivhaus schools and net zero pathfinder buildings.

However, he raised concerns that 鈥渢here are no standards or directives. There is nothing to refer back to and go 鈥檙ight, this is what we鈥檝e done, this is how it aligns with the standards鈥�,鈥� adding that 鈥渋t means there鈥檚 a lack of a baseline to work from鈥�. 

Andrew Eastland, employers鈥� agent at Longhurst Group, a housing association based in the Midlands, said: 鈥淲e鈥檙e doing quite a lot on operational net zero (Part L); we鈥檙e using heat pumps. We鈥檝e got our eye on that; we try and tackle it and we鈥檙e doing well in that area, but I think embodied carbon is not something we鈥檙e really thinking about at all.鈥� He added that there needs to be an incentive: 鈥淚f nobody is telling us to do it, we鈥檙e not looking at it.鈥�

Client buy-in

Another point raised during the discussion was that contractors will deliver net zero buildings if there is a clear demand from clients. However, the absence of regulation or incentives to support this makes it less likely to happen.

Andrew Carpenter, chief executive of the Structural Timber Association and Constructing Excellence Midlands, said that, in his experience, the construction industry changes for two reasons: 鈥渋f the client thinks it鈥檚 a good idea or secondly if it鈥檚 regulated鈥�.

Dave Wakelin, director of sustainability at Gleeds, said: 鈥淲e鈥檝e got clients that have got very strong green credentials. They鈥檝e seen the benefits and they鈥檙e the ones that lead the way and take more risk as well.鈥�

Carl Rushton, head of sustainability at construction firm McLaughlin & Harvey, said that client attitudes towards sustainability vary.

He mentioned that some clients prioritise sustainability, having worked with a sustainability consultant and adopted processes like PAS 2080, a standard for managing carbon emissions in the built environment. These clients approach Rushton鈥檚 team with comprehensive carbon models to request pricing for their projects.

Other clients, he finds, say they don鈥檛 care about carbon; they just want the project to be built. Some say they haven鈥檛 thought about sustainability, but ask Rushton what his team can do. Rushton said that with a lot of clients, even those initially committed to sustainability, he finds 鈥渨hen we go back with the price, it鈥檚 not quite what they expected and they usually start value engineering or just chopping stuff out鈥�.

Rob Nield, director at Webb Yates Engineers, said his company is making good progress towards delivering more sustainable, net zero in operation and timber buildings, but there is little incentive to do so.

He said: 鈥淭he project works where there is an incentive to do it; that鈥檚 because the company wants to provide a low carbon or net zero building. Their business case is that if they produce that building they鈥檒l get better rents for it.鈥�

He added that big companies want to commission sustainable buildings because of their environmental, social and governance (ESG) credentials.

鈥淭here is a market there for it. But very few are doing it. So unless there鈥檚 some levers pulled to create financial incentives or regulatory incentives to do it, nothing鈥檚 going to change,鈥� he added.

Increasing the use of timber

Speakers around the table agreed that timber is currently not widely used in housebuilding, and that this option could be explored more. But could that soon change?

In December last year, the previous government launched a timber roadmap setting out a vision to increase the amount of timber used in the construction of homes and buildings in the UK. It introduced an implementation plan in May, but then the election was called.

Carpenter, who was due to meet with a minister in the Department for Environment Food & Rural Affairs soon after the roundtable, expressed optimism about the new government鈥檚 plans, based on the Labour party conference at the end of September. 鈥淚 think the Labour government are going to push or maybe even accelerate the [timber] agenda,鈥� he said. 

The Structural Timber Association (STA) is working with Confor, the Confederation of Forest Industries, to try to increase the amount of structural timber produced in the UK. At the moment, 5% or less of structural timber is homegrown. 

The STA recently produced a capacity report for Homes England, which outlines that 100,000 homes per year could be produced using timber. One of the STA鈥檚 asks of government is that it consider timber as part of the solution to the housing crisis. 

Eastland said that only 10%-20% of Longhurst Group鈥檚 homes are timber framed. 鈥淕iven that most of our procurement is design and build, it鈥檚 probably because we鈥檙e not overly prescriptive about what to use 鈥� we鈥檙e just asking contractors to design in line with building regulations.鈥� He acknowledged that Longhurst may need to be more specific about using timber but mentioned that 鈥渃ost and viability might also be an issue鈥�.

Robert King, director at architect Howells, said his practice had only used timber to a significant degree on 鈥減robably a handful鈥� of projects, such as the National Memorial Arboretum and the Savill 黑洞社区. 鈥淭hey tend to be really successful, award-winning buildings,鈥� he said, highlighting that timber buildings do 鈥渢end to be in the civic sector or community-led buildings鈥� and the struggle for the industry is 鈥渉ow do we take that learning and bring it into the commercial and residential sector?鈥�.

King said that on the Elephant and Castle regeneration project on which he worked, which had planned to deliver 300 new homes using cross-laminated timber (CLT) framing, 鈥渂ecause of regulation challenges that [the CLT] got scrapped and the high-rise blocks went back to concrete鈥�.

In the end, some of the three-storey CLT-framed townhouses were brought forward, which King described as 鈥渁 step in the right direction鈥�, adding: 鈥淚 think more opportunities for hybrid structures should be explored.鈥�

In the wake of the Grenfell Tower fire and the introduction of the 黑洞社区 Safety Act, there is now a preference in the industry 鈥渢o just stick with what is known and accepted鈥�, he said.

Wakelin raised the point that the 黑洞社区 Safety Act has made designers hesitant to use timber in taller buildings in particular. He wondered whether 鈥済overnment could go in and help manage the risk designers are taking, because everyone is so scared of designing buildings over 18m due to the 黑洞社区 Safety Act and insurers won鈥檛 touch them鈥�.

Carpenter said the STA is focusing on safety and recognised the reluctance to build above 18m with timber. However, he insisted that 鈥渋t can be done鈥� and cited Hackney council as an example, noting that it has built timber structures up to 10 storeys high.

Policy improvements

Returning to the topic of Part Z, the panellists agreed that this regulatory amendment is a key policy improvement they would like to see implemented. They believe it could play a significant role in helping the sector achieve net zero.

Carpenter said: 鈥淲e鈥檝e all talked about Part Z, but that is the game-changer. We need the government to show their leadership and bring Part Z in, to get the embodied carbon argument across the line.鈥�

In France, he added, the government has stipulated that 50% of all publicly funded buildings need to be constructed using natural materials. 鈥淚t鈥檚 that sort of leadership that I think is necessary from government if they really mean to get to net zero by 2050,鈥� he said. 

Michalska-Morris expressed her support for Part Z but noted that one of the problems with Part L was that 鈥渋t was rushed, not properly consulted on, and has been a headache鈥�. She emphasised that the government should engage industry experts, rather than relying solely on input from government officials.

Nield compared Part Z to the impact of Part L when it was introduced 10 years ago, stating that it spurred the industry to develop, innovate and reduce costs. If that [Part Z] comes in it will cause some ripples: some people will go out of business, some will have to sharpen up and learn some new things, but that鈥檚 really it,鈥� he said.

He added that, as a practice, Webb Yates Engineers has been calculating embodied carbon in its buildings for the past 15 years. He said this is important as 鈥済enerally we are the ones that are culpable for creating all that embodied carbon because it鈥檚 on our drawings鈥�.

Nield said that in conversations about net zero, sometimes people say they don鈥檛 know what they鈥檙e doing and that they don鈥檛 have the answer, which he rejected as 鈥渦tter nonsense鈥�, adding: 鈥淲e know what we need to do; we鈥檝e got the tools 鈥� we just need to do it.鈥�