5 ways different people on a project can slash carbon emissions

You might be all too aware that the construction industry is one of the largest carbon emitters in the world (about 40%).

If you’re a designer, you’ve likely felt that the pressure of reducing your project’s emissions falls on you.

Granted, the ability to influence how much carbon our projects produce is greater at the start, before spades hit the ground.

But we all have a duty to protect the environment.

Below are five ways that different stakeholders across the project lifecycle can make greener choices.

1. The influential client

The client defines the purpose of a project. They have the most influence in ensuring green choices are made at every stage.

A key way they can do this is by implementing the X29 Climate Change clause of the New Engineering Contracts (NEC).

This optional clause enables clients to state their climate change requirements (CCR) in the scope (i.e. net zero, biodiversity). Contractors then detail their strategy for achieving this.

The consultants and contractors working on the project must be clear on what they’re able to deliver and engage with the client about this early on. Because once included in the project contract, these requirements must be met.

But it’s best to think about it as a means of building strong partnerships, rather than a way to prosecute if things go wrong.

The clause has been gaining popularity.

For example, construction company Skanska used it on the A428 highways project, sharing that early engagement and clear simple language is essential to successfully implementing X29.

Learn more about how the project used X29

2. The thoughtful consultants

Consultants – be they architectural, civil, environmental, etc – should look to implement irreversible decisions to reduce carbon in the design.

For example, opting to reduce slab thickness is a more fundamental decision that’s less likely to be changed than, say, choosing a greener type of concrete.

Material specification, while important, could be considered more superficial and subject to change, especially if there are procurement issues.

Consultants can also share design decision logs that clearly outline the reasoning behind carbon conscious choices, helping to prevent changes further down the line.

Understanding where emissions come from

The design does directly affect the embodied carbon of a scheme.

So, it’s important for the design team to really understand where it’s coming from.

According to The Structural Engineer, most of the carbon is associated with slabs, followed by walls, foundations and finally, columns.

This can then become a balancing act, because to add more columns, you may need more foundations, but it can lead to less carbon overall than just using thicker slabs.

The tightrope act gets increasingly difficult when you factor in the whole lifecycle of the structure. For instance, by adding more columns to a building, are we restricting what it can be used for in the future?

The key to making these sometimes difficult decisions? Data!

By learning from how others have approached things and using technology (e.g. parametric modelling) to generate different options, we can make smarter choices, faster.

3. The considerate contractors

When projects get to site, the discussions are typically about reducing cost and programmes.

Rarely do we hear “let’s make a change here as it has the potential to save X tonnes of carbon”.

Therefore, much like the Considerate Constructors Scheme – which seeks to raise standards and trust in the industry – we need our contractors to be ‘considerate carbon constructors’.

There are many ways to do this:

• Being aware of how changes impact project carbon
• Employing less carbon intensive techniques
• Avoiding error and rework
• Implementing electric plant and ‘no idling’ schemes
• Reducing temporary works
• Minimising waste

The TARMAC Pave project on the A64 road in North Yorkshire is a great example of a contractor’s efforts to reduce carbon.

The project team used low-carbon materials, recycled planings and zero emission equipment, alongside an echelon paving technique (simultaneous lane construction) that reduces maintenance requirements.

The smoother road surface improved ride quality, lowering fuel consumption for users.

These measures achieved significant carbon savings: 70% during construction, 7% during operation, and 260 tonnes from reduced maintenance.

4. The innovative suppliers and manufacturers

A large part of a project's embodied carbon is tied to suppliers and manufacturers, making this a key area to target.

Collaboration and engagement are essential for driving innovation to reduce carbon emissions from raw material procurement, energy-intensive manufacturing, and product transportation.

Accounting for procurement and production lead times of sustainable materials is also crucial to prevent defaulting to traditional construction practices.

Be strategic

Our industry’s main material suppliers should have decarbonising strategies.

For example, building materials company, CEMEX, has identified and implemented different strategies to reduce carbon, such as:

• Reducing clinker quantity in their cement mix (responsible for cement’s high carbon emissions)
• Using electricity from clean sources in their operations
• Moving to low carbon transport

5. The unified industry

Why would the industry be a project stakeholder? Because it has a vested interest in project outcomes.

Every action provides an opportunity to learn; whether we gain best practices or decide not to repeat something.

By sharing knowledge and data, the industry can accelerate progress toward a sustainable built environment and make more informed decisions on future projects.

The industry already excels at developing and sharing guidance.

For example, the PAS 2080 carbon management standard has helped empower the industry to make changes within their companies.

The ICE, home of infrastructure, has an ever growing Knowledge Hub built on the very purpose of creating a unified industry.