23 June 2022 | by

What is a circular economy?

While sustainability has become a key topic in the construction and other industries, most of the world's economy still relies heavily on a linear "take, make, dispose" economy model requiring:

  • Access to enormous quantities of cheap and accessible materials and energy.
  • Large areas in which to dispose of products or parts at the perceived end of their lifecycle.

However, we have woken to the fact that we have reached the point where we are 1) running out of those massive quantities, and 2) waste accumulation and disposal have become problematic.

Enter the ideology of a circular economy. In circular thinking, materials, components and products are kept at their highest use and value throughout an extended lifecycle. The focus from beginning to end is on restoration, regeneration and reuse rather than disposal.

Moving from linear to circular thinking

Design waste out of the production model.

With biological waste, any toxicity threats are eliminated by design, thus allowing materials to be composted. With non-biological materials, we emphasise upcycling, which is a step change from how we currently view recycling.

Rather than relying solely on reduced quality (downcycled) products made from recycled materials, we try to opt for compounds that can be reused repeatedly with minimal energy expenditure and maximum quality retention (upcycled).

Design products to be both resilient and efficient.

In circular thinking, key design features include versatility, adaptability, and modularity, focusing on creating diverse systems that can better withstand external pressures rather than systems that are simple and efficient but have limited lifespans.

Integrate and connect systems to minimise waste and reduce fossil fuel use.

An excellent example of this idea in action is the agricultural industry. While agricultural production relies heavily on solar energy, fertilisers, machinery, processing systems, etc., depend on fossil fuels. By integrating these systems, one system's by-products and waste can be captured and used by another's – adding additional value whilst reducing waste and fossil fuel reliance.

Examples within the built environment include products like ferrock, a building material created using industrial waste such as steel dust and ferrous rock. Ferrock is relatively new but, thus far, appears to be more resilient than concrete. Another example comes from an Australian company called Close the Loop, which works with manufacturers to create value from waste. For instance, instead of going to a landfill or ending up in our oceans, old printer cartridges and soft plastics are retained and mixed with asphalt and recycled glass to produce a higher-quality, longer-lasting road surface.

Move away from cradle-to-grave thinking

The baseline assumption in a linear-focused economy is founded on a one-way system: raw materials are extracted and turned into usable products, which are then disposed of at the end of their life. Within this type of economy, any focus on sustainability, eco-friendliness etc., is bounded by this linear, cradle-to-grave viewpoint. Even when we make efforts to recycle materials, we rely heavily on methodologies that decrease the material quality and limit usability, thus reducing desirability.

Think reuse: cradle to rebirth

In circular thinking, the effort is on minimising the volume and velocity in which materials flow through the system to their inevitable end. While some materials can and should be recycled, the intent is to avoid downcycling where possible.

With non-biological materials, the focus is on applying systems thinking – examining how products form relationships with other products and how the materials can flow through them to create the most effective use of each component and minimise the need for new raw materials. Instead of creating an inferior recycled product, the emphasis is on creating an equal or higher quality one. For instance, whole wine corks are combined with recycled granulated corks to form wall and floor tiles.

With biological materials, the thinking is similar, but rather than applying systems thinking, we think in terms of a waterfall, with materials cascading through other applications, thus harnessing and taking advantage of the value provided by each stage of a material's natural decomposition process. One example is harnessing mycelium, a bacteria found in rotting organisms. You can create biodegradable insulating and packing material by placing mycelium in a mould to control its shape during growth and then stopping growth via high heat to retain that shape. The sheer impact of biodegradable packing materials alone is astronomical, reducing millions of tonnes of non-biodegradable waste yearly.

BSI circular framework guidance

BS 8001– Circular economy

BSI introduced BS 8001 in 2017 as an effort to help organisations map out their specific system and better understand the benefits of adopting circular economy thinking:

  • Unlocking new opportunities.
  • Creating new revenue streams.
  • Capitalising on cost savings.
  • Becoming more resilient to external shocks, shifts and disturbances.

    This framework standard provides a comprehensive and practical guide that is flexible enough to be used by organisations at any point along the circular economy journey. It also provides a talking point, a place to begin the discussion regarding how any single organisation fits into the circular economy idea. Because determining where a business fits in is the key. No one organisation can be circular by itself. Creating a circular economy is a team sport.


    The BS 8001 circular economy framework guidance highlights six principles underlining circular economy thinking. They are:

  • Systems thinking – Understanding how what you do impacts things system-wide.
  • Innovation – Looking at how you manage resources with a mind to creating additional value.
  • Stewardship – Being aware of the knock-on effect of every decision and action you take and then taking responsibility for the results.
  • Collaboration – Working with others towards a common goal.
  • Optimising value – Ensuring that materials, products and components always remain at their highest value and function.
  • Transparency – Being open and honest about both the barriers and benefits.

Issues and challenges

As with all our sustainability efforts, while good things are happening, some issues must be addressed to bring them up to scale. Examples include:

  • The interfacing between chemical waste and product legislation and the fact that our current waste law is designed for a linear economy.
  • Our biased thinking assumes any product or material that has been recycled, reused, or refurbished is inferior to something brand new.
  • How we mistakenly apply linear thinking to our ideas of what constitutes sustainability.
  • Ending fragmentation in the value chain, addressing transparency, competition concerns, silo working practices, and financing. Where does the responsibility fall?
  • How to create industrial symbiosis – connecting companies so that one's by-products and waste becomes another's raw materials.

    For the construction industry, a vital issue is the incentive. Stakeholders in the design and construction of a building are typically not the ones invested in its use once it's built. So, the question is how to create that connection and make it mean something?

How to make it work for us, and where do you fit in?

The place to start is incorporating sustainability into every aspect of an asset's lifecycle, beginning with conception, design and specification.

  • From the beginning, we conceptualise what happens after a new build fulfils its original purpose.
  • Instead of bulldozing and replacing older assets, we consider how they can be retrofitted and repurposed.
  • Once the asset has reached its true end of life, we determine how best to reuse the elements and materials within that asset.

When specifying, taking a sustainable, circular approach from Stage 0 and interweaving it throughout the specification process can go a long way in moving us towards our goal of a minimum waste economy. Once we turn the asset over, the specification becomes a living document from which owner and users – present and future – can continue to draw on to ensure it has a long life in which it can change and grow as new needs, requirements, and uses arise.

That's great, but how does it benefit us to make this change?

According to the World Economic Forum, in 2019, we extracted and processed over 92 billion tonnes of raw materials, constituting half of the global CO2 emissions. The end-of-use waste – plastics, textiles, food, electronics, etc. – is not just detrimental to the environment; it is seriously harming human health. However, planet and health concerns aside, while there is no guarantee that any organisation will benefit financially from the circular economy, adopting the principles will increase the possibility. A 2015 report by McKinsey & Company predicted the potential for €1.8 trillion in net economic benefit for Europe alone as early as 2030, suggesting that there is a compelling business case to be found in adopting circular economy thinking in everyday business activities.

Additional sustainability resources

The Construction Information Service

For CIS users, there is already a wealth of sustainability-related information in the comprehensive collection of industry-relevant publications we provide access to. NBS users with a CIS subscription can also use embedded links across specifications platforms to access research and reference documents.

NBS: Sustainable Futures Report 2022

NBS published our latest sustainable futures report in spring 2022. The report is the result of an industry-wide survey to understand the current situation regarding sustainability, the barriers we must overcome and further insights. To date, this report remains our most 'downloaded' survey, which supports the view that sustainability is the highest priority for our industry.

NBS Webinars and Articles

To help guide and educate our customers, we have created a sustainability webinar series covering topics like sustainable outcomes and the RIBA Plan of Work, becoming a sustainable business, and promoting your sustainability activities and credentials. The webinars are linked at the bottom of the 'Sustainability with NBS' webpage. The hub also provides access to a selection of sustainability-related articles, and you can find more in the 'Knowledge' section of the NBS website.

RIBA Plan of Work 2020 and the Sustainable Outcomes Guide

With the 2020 release of the RIBA Plan of Work, the RIBA has responded to an escalating industry need for an expanded sustainability strategy by mapping sustainability targets to UN Sustainable Development Goals and aligning them with the RIBA Sustainable Outcomes Guide. To explore this and other ways that the new Plan of Work can benefit you, NBS has a webinar series that addresses several topics, including sustainability, fire safety, conservation and inclusive design.

RIBA 2030 Climate Challenge

The RIBA 2030 climate challenge was initially launched in 2019 and has since been revised in 2021 to align more closely with the industry's strive to reduce whole-life carbon.

UN Sustainable Development Goals

The 17 United Nations Sustainable Development Goals set clear areas of focus for the world to become more sustainable in all environmental, social and governance aspects.

UN Climate Neutral Now

The UN Climate Neutral Now campaign calls for members to voluntarily sign up to the scheme and pledge to measure, reduce, contribute and report on their emissions impact. For more information on the campaign, you can visit the UN website.

Specifying with NBS Chorus

NBS has seen a steady rise in requests for information on how our technical content can help specifiers achieve sustainable outcomes. In the article Using NBS to specify sustainable outcomes on projects, NBS explores how the RIBA Plan of Work and Chorus can be used together to tailor a project to meet sustainability expectations across the project timeline. Through NBS Chorus, you can access your specifications across locations and organisations. Chorus is suited to performance and prescriptive specifying and has editable clauses supported by technical guidance. Our content is reviewed to improve clarity and usefulness, informed by research, user feedback and industry drivers.

Sustainable product information through Source

NBS Source brings together NBS BIM Library, NBS Plus and RIBA Product Selector to provide a sole source for product information that seamlessly integrates into a project's workflow and provides an additional level of enhanced product data in a consistent, structured format. Many manufacturers listed include environmental and sustainability information in their product listings.