Constructing a new waste paradigm
The case for secondary materials use in construction.
The construction industry faces a serious and persistent waste challenge. In the UK alone, construction, demolition and excavation accounts for 61% of the nation’s total waste, amounting to 117.5Mt annually. The vast majority of this comes from demolition and excavation activity as we routinely knock down buildings and infrastructure, clear sites for new construction, and then move onto the next. This approach creates a relentless cycle of waste and resource consumption.
The construction sector is notoriously slow at adopting new practices. Projects are typically constrained by tight budgets, leading to a culture that is risk adverse. As a result, innovation, particularly in sustainability, is often diluted by the time a project reaches site.
The nature of the industry reinforces a linear model of resource consumption. We extract virgin materials from the natural environment, manufacture them into construction products, use them to build and eventually discard them – often into landfills, once the asset reaches the end of its economically valuable life. This cradle-to-grave approach is the core driver of the industry’s massive waste output and its unsustainable demand on natural resources.
So, what can be done? How can we reshape the industry to minimise its waste footprint while still meeting the growing demand for built assets?
The solutions are simple and also well understood among industry sustainability professionals. However, they must be urgently accelerated if we are to address this challenge effectively.
Option 1 – build less
At first glance, the idea of ‘building less’ might sound counterproductive, especially when demand for new buildings and infrastructure is driven by the housing crisis, urbanisation and population growth. But building less doesn’t necessarily mean a reduction in output, rather, it involves a shift from new construction to refurbishment and retrofitting of our existing building stock.
Of course, not every building is suitable for repurposing. Challenges, such as inadequate ceiling heights, poor access, outdated layouts, or non-compliant structural designs can limit retrofit potential. Still, too often we default to demolition because historically new has always been seen as ‘better’.
By preserving and adapting existing structures, we reduce avoidable demolition works and consequently the quantity of waste generated. However, the benefits of retention and retrofit over new construction go far beyond waste reduction. This approach also helps conserve the embodied carbon already invested in the building’s structure. Particularly the substructure and frame, which are typically the most resource-intensive elements, due to their reliance on concrete and steel.
Additionally, a well-designed refurbishment can deliver high levels of energy efficiency, often comparable to new builds. As our energy grid continues to decarbonise and technologies improve, the operational carbon gap between old and new buildings is narrowing.
As an industry, we should be leaning into this carbon benefit as a driver for retrofit and refurbishment. We are starting to see this option prioritised in certain markets through policy intervention, but it has not yet been adopted as standard practice across the UK.
With the industry focus on net-zero carbon, the development of the Net Zero Carbon Building Standard and the proposed Part Z of the building regulations, we will begin to see increased emphasis on refurbishment rather than new builds in the coming year.
We must educate clients and developers on the benefits of retaining existing structures, while policymakers and local authorities should question applications for demolition. By embracing the potential of the existing built environment, we can build less, while still delivering more value, preserving natural resources and minimising avoidable waste.
Option 2 – build better
Even with a strong focus on retention and retrofit, new construction will likely continue to dominate the market in the near future. Buildings and infrastructure eventually reach the end of their useful life, at which point they need to be replaced or upgraded. The challenge lies in the way we design and construct new assets, while facilitating material recovery.
When demolition is unavoidable, waste reduction and resource preservation should be a key priority. Pre-demolition and pre-refurbishment audits are essential tools for identifying valuable materials that can be recovered before strip-out works begin.
Too often, usable materials are discarded simply because we don’t know what’s there, or because recovery hasn’t been planned in advance. By auditing and cataloguing materials, we can create opportunities for reuse in new projects, avoiding unnecessary waste.
When paired with appropriate logistics, storage and matching platforms, this approach reduces landfill, conserves resources and reinforces a circular economy model where materials retain value well beyond their first use.
Most buildings and infrastructure assets are not designed with material recovery in mind. They are created as bespoke, site-specific constructions, often with materials and components joined using adhesives, cast-in-place methods, or complex finishes that make disassembly nearly impossible. We also frequently lack comprehensive knowledge about the materials used, meaning opportunities for reuse or recycling are missed. To address this, we must rethink how we build.
We can learn a great deal by observing other industries. In manufacturing, products are designed for standardisation, efficiency and often for disassembly. Processes are tightly controlled and optimised, which significantly reduces waste. By contrast, the construction sector still relies heavily on manual, onsite and custom assembly methods that are inherently less efficient and more wasteful.
One promising solution is a shift towards offsite construction. By moving the building process into controlled factory settings, we gain greater precision, reduce material waste and ensure quality is more consistent. Modular and volumetric construction techniques can produce entire building units that are then assembled onsite. These systems can also be designed for future disassembly, allowing materials to be recovered and reused at the end of the building’s life, which facilitates a circular economy approach.
Of course, a complete shift away from traditional construction practices won’t happen overnight. But we can begin today by adopting design strategies that prioritise efficiency and modularity, even for traditional builds. These might include standardising window sizes, aligning floor heights to fit off-the-shelf materials like plasterboard, or designing structures that allow for future component replacement without demolition.
The ultimate goal is to view buildings not as static, permanent objects, but as material banks – dynamic repositories of resources that can evolve over time. Materials should not be seen as having a single life within a structure. Instead, their use within a building should be just one phase in a longer, regenerative lifecycle.
Licensed for reuse
A critical enabler of this circular transition is the improved collection and management of data about the materials used in our buildings. Too often, materials become waste not because they are no longer useful, but because we lack the information needed to assess their quality, origin, or suitability for reuse.
This is where material passports come in. These are digital records that document the specifications, composition and lifecycle performance of construction products and systems.
By embedding data into a building’s fabric from the design stage, material passports allow future stakeholders to make informed decisions about recovery, recycling, or reuse. They act as a bridge between today’s design choices and tomorrow’s resource needs, unlocking long-term value from what would otherwise become waste.
As the construction industry moves towards a more circular model, accurate and accessible material data will be fundamental in turning our buildings into reservoirs of reusable resources, rather than endpoints of material consumption.
A thriving secondary materials market is essential to unlocking the full potential of a circular economy in construction. These markets enable the exchange, resale and redistribution of reclaimed or surplus building materials, transforming potential rubbish into useful resources.
By creating accessible platforms that connect suppliers of used materials with designers, contractors and clients, the industry can reduce demand for virgin resources while lowering costs and carbon footprints.
However, for these markets to function effectively, transparency and standardisation are key. Buyers need confidence in the quality, performance and compliance of secondary materials, which requires robust certification systems, quality control processes and logistical support.
When supported by policy and integrated into project planning from the outset, secondary material markets not only divert waste from landfills, but also help normalise reuse as a practical, scaleable and economically viable alternative to conventional procurement.
The waste problem in construction is surmountable, but it demands decisive action, cultural change and systemic innovation. We must challenge outdated assumptions about what constitutes progress in our built environment. We must place greater value on the resources we consume and recognise the long-term environmental costs of our design decisions.
By choosing to build less and build better, the industry can lead the way towards a more circular, more resilient and low-carbon future. It’s time for the construction sector to move past incremental improvements and take on meaningful changes that reduce waste and and rethink how we approach resource circularity.
