Q&A: Holcim's Kaziwe Kaulule on Sustainable Construction

The construction industry's shift toward circularity requires leaders who can bridge commercial growth with environmental imperatives. Managing Director Kaziwe Kaulule is driving this transformation at Holcim UK's aggregates and recycling division, where he's been advancing ambitious sustainability targets since joining in November 2023.

"I am passionate about people-first leadership, ensuring teams are empowered while driving high performance, commercial agility and environmental responsibility," Kaziwe explains. His approach combines workforce development with environmental goals, emphasising apprenticeships and inclusiveness initiatives.

Under his direction, Holcim UK is investing in recycling centres nationwide to process demolition waste at scale. The strategy focuses on "transforming the aggregates industry through sustainability-driven growth, circularity, and innovation to meet customer's evolving needs."

The company leverages AI-driven safety measures and digital solutions while championing circular economy principles. Kaziwe's vision is making "sustainable products become the norm, not the niche" through accessible, market-leading solutions that enable easier adoption across the construction sector.

How is Holcim leading the charge in making sustainable construction a reality?

There are three central pillars of our plan for making sustainable construction a reality. The first is decarbonisation. We are redoubling our commitment to climate action by reducing carbon in our product and service offerings. We’ve embraced cutting-edge carbon capture technology – as well as alternative fuels and materials, particularly in our Cement and Ready-mix operations – implemented more accurate reporting and renewable energy generation across our UK sites and adopted a flexible approach that takes advantage of cleaner, cheaper energy generated by wind and solar. 

The second pillar is circularity and waste reduction primarily driven by our Aggregates and Asphalt business units. Key initiatives to aid in this mission include recycling and landfill diversion efforts, material recovery through increased use of reclaimed asphalt pavement (RAP), and a reduction in water intensity throughout our operations, implementing freshwater replenishment programmes beyond our site boundaries, and treating the water we use when it returns to nature.

The third and final pillar is smarter construction using digital tools, building under controlled conditions, and improving quality and process control. To support this, we are integrating more additive manufacturing techniques across the business, and are scaling our use of AI across more than 100 plants worldwide over the next few years, improving efficiency and reinforcing capacity for customers.

How will Holcim achieve its goal of raising recycled content from 7% to 20%?

Circularity is a goal we are committed to, which is why we are targeting 20% of our products made from recycled materials by 2030.

To deliver on this, we have invested significantly in expertise, including our member business Land Recovery, a leading supplier of recycled construction materials to the rail industry with our flagship recycled ballast products. Meanwhile, we have invested significantly in our Construction Demolitions Materials (CDM) handling capability at our recycling centres in key locations, such as London and Birmingham.

Our ECOCycle range of aggregates, asphalt and concrete, which is third party verified, incorporates a minimum of 10% recycled CDM, enabling new to be built from old without compromising on performance.

How will new construction and demolition recycling centres link to plants and customers?

We are investing considerably in expanding our network of construction and demolition recycling centres across the UK. Our major investment in our CDM recycling centre in Birmingham is emblematic of this pledge and reinforces our commitment to leading the development of circularity in the construction industry.

The site is equipped to receive and process up to 250,000 tonnes of material annually, including asphalt planning, concrete waste, mixed hardcore, brick and rubble. All materials are crushed, sized, screened and processed on-site, while recycled asphalt is returned to our Express Asphalt plant, and recycled concrete is fed into our readymix concrete (RMX) operations. Additional aggregate products are made available for bulk or bagged collections for the local market, ensuring 100% recycled CDM materials are reintegrated in the construction supply chain.

Reducing waste to landfill, promoting the reuse of water, preserving natural aggregate sources and integrating more renewable energy generation throughout our operations are among the key drivers of the circular economy. As such, we aim to increase the use of CDM and recycled building materials across the UK and will continue to invest in sites to grow our CDM capability for customers nationwide.

Where does Holcim UK’s net-zero plan go beyond government policy?

In 2023, we launched our net zero strategy, covering all aspects of operations with a set of measurable targets. We now conduct live reporting at each site, as well as quarterly oversight meetings across all leadership teams to track our progress.

According to our figures for 2024, scope 1 and 2 emissions have fallen by 117,000 tonnes, representing a 23% reduction in absolute emissions year-on-year, and our lower emissions per tonne of product at 15.1kg Co²e. We are aiming to reduce total emissions by 37% by the end of the year – which we are on track to achieve – 68% by 2030, and to ultimately reach net zero by 2050.

We are proud to have been the first company in our industry to have 2030 and 2050 net zero targets aligned with a 1.5C pathway validated by the Science Based Targets initiative, a global framework for setting greenhouse gas emission reduction targets in line with climate science.

As the construction industry continues to grow – with ambitious targets to meet – the role of recycled materials in products will become ever more important to the delivery of sustainable buildings. By bringing innovative, sustainable building solutions to our customers across all product categories, we can demonstrate how cleverly designed products help companies achieve their sustainability construction goals.

What single 2026 metric will prove circularity and nature-positive gains?

The most meaningful single metric could be the percentage of total products using recycled materials sourced through nature-positive supply chains, as this demonstrates circularity while ensuring biodiversity gains.