The sustainable benefits of natural stone

Despite being one of the Earth’s oldest natural building materials, natural stone and sustainability haven’t always been seen as synonymous with one another.  This is perhaps because while other materials without such organic origins had to work hard to claim sustainability credentials, natural stone was viewed by some as an ‘old-fashioned’ material, more at home in an age where sustainability and climate change awareness were less of a priority.

However, there is an ever-increasing awareness within design that, ironically, some of the most ‘old fashioned’ materials provide solutions to our most modern issues of climate change and an increase desire to source sustainable products and materials.

Natural stone can be an excellent choice for your next interior design, even for those designers that prioritise energy efficiency, low emissions of greenhouse gasses and renewable energies. In fact, as we'll argue in this article, the durability of natural resources such as stone allows designs to have a long life-span and thus stay beautiful and relevant for a long time. Of course, issues like mine safety and the health of local economies are relevant to this conversation, and choosing which stone abides by strict guidelines of sustainability is not beyond the designers' responsibility.

To help us understand natural stone's best practices, we've enlisted the help of the Stone Federation Great Britain to explore the sustainable benefits of natural stone. Thank you to Matt Robb, Digital Media Executive, Stone Federation, for sitting down with us!

Find out whether stone is the most sustainable building material by scrolling below.

Meet the British Stone Federation

Stone Federation, the natural stone industry's official trade association, is a valuable resource for architects, designers, specifiers, clients, and the construction sector. With a century of experience and a diverse membership, Stone Federation provides essential support to those in the natural stone business in Britain.

Q: How do you define sustainability?

A: From Stone Federation’s viewpoint, when we talk about sustainability, we’re assessing the environmental and social impacts throughout the whole life cycle of a project which includes the raw material extraction, production, distribution, use and end of life. At present much of our focus is on the environmental impacts and, in particular, the demands of the low carbon agenda but we are always conscious of the social and ethical responsibilities.  From our perspective, the fewer processes required to get from raw material to finished product the better for the environment and the more sustainable the material.

For natural stone the process is relatively simple: stone is quarried or mined from the ground, cut into slabs or tiles, transported to site and will often last for decades, and in many cases, centuries.

While some ‘stone alternative’ or ‘stone effect’ products require intense heat and pressure to bond the resins, pigments and other ingredients, natural stone comes out of the ground ready to be cut, finished, and fixed.  

Natural stone is, by definition, a natural product, formed in the Earth over many millions of years, extracted, cut to size, and transported to site, without excessive human intervention and invention.

This dynamic of durability is another metric for assessing sustainability in surface design – how long will this material last?

So many of our nation’s historic hotels, churches and public buildings have natural stone floors that are 100s of years old and still performing well.  It is very rare to find the same with some of stone’s competitor materials such as engineered stone.  Much of this strength is thanks to the millions of years of compressive geological processes that go into the natural formation of stone.

Another way to assess sustainability in surface design is to look at a material’s ability to be reused or recycled should there be renovations or change of use.  Natural stone, thanks to its durability, can be reclaimed, reused, or even repurposed as furniture or pieces of art.

Q: Greenwashing has been taking over the design world, unfortunately. How can this be addressed?

A: There is no avoiding it. Sustainability has never been as high on the agenda as it is now, and therefore every material and industry wants to portray itself in a way that fits with this current design narrative.

Looking beyond the ‘green’ logos and planet-hugging graphics and engaging with some common sense principles in a great place to start. A good first question to ask would be, ‘is this material a natural one’. By this, we don’t mean something that includes natural elements, but something that is, in its entirety, a natural product. For example, engineered stones have some natural stone within them but also have resins, dyes, etc. so are a less sustainable choice then using the original natural material – stone – rather than a man-made alternative.

Material comparison tools and studies are another great way to cut through the ‘green-washing’ and objectively compare the sustainability credentials of different materials. EPDs, the ICE Embodied Carbon Database are both great places to start.

Q: How does natural stone compare to its alternatives?

A: When comparing natural stone with large-format ceramics, terrazzo, and other flooring products, stone’s global warming potential was found to be significantly lower. The GWP figures showed that, for example, large-format ceramic tiles have a 74% higher Global Warming Potential than natural stone and terrazzo are 27% higher.

There are many other examples of studies that have demonstrated the sustainability credentials of natural stone. Moving slightly away from interiors, but still on the topic of sustainability there was also a project in London, 15 Clerkenwell Close, where the use of load-bearing natural stone instead of a concrete and steel structure reduced the whole-life carbon footprint of the building by 95% and the cost by 75%.  

Finally, the Green Guide to Specification, which is part of BREEAM, sets out an A+ to E ranking system for the environmental performance of materials. In a case study project by the BRE, almost half of the natural stone-related components achieved either A+ or A and the majority of the remainder scored a C or above.

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Thank you for reading this article. If you enjoyed the topic of designing to withstand the test of time, check out our Journal for more content. In particular, you'll enjoy this article on sustainable architecture.