Sustainability
Building a Sustainable Future: The Innovative Materials That Are Tackling the Climate Crisis
Estimated reading time: 10 minutes
Podcast version
Shelter is a basic human need, but our buildings do more than simply protect us from the elements. The design and function of the buildings around us, both public and private, define how we live our lives. They give us a sense of place, act as markers of our history, and help shape our cultural identity.
As the climate crisis deepens, the urgent need to find more sustainable solutions is as vital in our buildings as in the rest of our lives. According to a 2020 report from the UN Environment Programme, the building sector now accounts for 38% of global carbon dioxide emissions, making it a key contributor to climate change.
An estimated half of those emissions are down to the energy we use to heat and power our homes, according to the UK’s Green Building Council. The need for clean energy solutions is something we’ve discussed before. However, the construction of new buildings and the maintenance and repair of existing ones also has a huge impact on the environment.
The Environmental Impact of Building Materials
Transport and construction processes contribute to carbon emissions. However, it is the materials our buildings are made from that has the biggest effect on their carbon footprint during the construction phase, contributing 55% of the energy used in creating new buildings.
Carbon emissions aren’t the only concern either. Building materials must come from somewhere. Often, extracting materials for buildings is damaging to the environment, with quarries and mines disrupting natural habitats and causing environmental pollution.
Many of these materials are non-renewable too. Stone, clay for bricks, sand for cement and glass – these are all resources that are repeatedly depleted by our hunger for new building materials.
Once extracted, those building materials need to be transported, often around the world. Where our ancestors once used the resources from their local area, the modern construction industry moves vast amounts of materials every day, adding to their environmental impact.
Even once finished, our buildings still require repair and maintenance. When construction materials only have a short lifespan, they need to be replaced regularly, adding to the environmental impact of the building during its useful life.
In the meantime, discarded building materials contribute to our waste problem. Figures published by Defra show that the construction and demolition industry was the biggest generator of waste in the UK in 2018.
Is a Greener Future Possible for Our Buildings?
Fortunately, it isn’t all grim news for the construction industry. Plenty of exciting and innovative new materials are appearing that aim to increase the sustainability of our building stock.
We’ve put together a list of some of the most interesting sustainable innovations from recent years. Not all are commonly available on the market yet. Still, there’s plenty of evidence that a greener future is possible for our buildings.
Alternatives to Concrete
Concrete is a vital material in modern buildings around the world. Economical, easy to mould, and weather-resistant, it is easy to see why this material is so popular. It is now the second most widely used substance on the planet, beaten only by water.
Unfortunately, concrete is also a building material with a high carbon footprint. One of its primary ingredients, Portland cement, is responsible for a whopping 7% of global carbon dioxide emissions.
Reducing the carbon footprint of concrete is an urgent issue. So, it is fortunate that new solutions are coming forward to make concrete more sustainable.
Extending the life of traditional concrete is one option to explore. One of the issues with concrete is that it is prone to microcracks. These tiny cracks may not be visible to the naked eye, but they allow water to seep into the building.
Water is a problem in any building, as anyone who has lived with damp knows. In concrete buildings, it can rust the reinforcing steel rebar used to support the concrete, shortening the life of the building.
Fortunately, there are now forms of concrete that can self-heal, closing microcracks before any water can enter the building. Although there are a few options out there, one that has shown significant potential uses bacteria, which excrete calcite to fill and repair small cracks.
The bacteria can remain dormant in the concrete for up to 50 years. When they come into contact with water they are activated and start to excrete calcite, which seals the cracks before any further water can get in.
Pretty clever for a single cell organism.
Another option is to change the raw materials used to make the concrete in the first place. That’s the approach taken by the DB Group, manufacturers of Cemfree, a type of concrete that is made without Portland cement. Instead, they use ground-granulated blast-furnace slag and pulverised fly ash.
The DB Group claim that switching to Cemfree can reduce the embodied carbon in a building by up to 80%.
Self-healing concrete
Source: Flickr, © UCL, Institute of Making/Robert Eagle, used under CC BY-ND 2.0, cropped image.
Or how about Hempcrete, which uses a mixture made from the woody core of the hemp plant, mixed with lime? A breathable material, Hempcrete’s lime content means it absorbs carbon dioxide from the atmosphere, making it a ‘better than carbon-zero’ alternative to traditional concrete.
Bio-Based Building Materials
Hemp isn’t the only plant that can be used in new ways to create more sustainable buildings. Researchers are increasingly finding ways to use biological matter to make building materials with a lower carbon footprint.
At Whitfords, we’re committed to offering you 100% plastic-free skincare and we’re already huge fans of the loofah plant (sometimes called luffa or sponge gourd). Best known as a natural bath sponge, loofah fibres are the raw material for our FibrePods – an innovative alternative to cardboard packaging that can then be used as a body scrub, before going into your home compost.
Green Charcoal by Shreyas More © SDI
And it seems we’re not the only ones embracing the potential of loofah fibres. Along with charcoal, they form the basis of a new type of biodegradable building block, called Green Charcoal. Developed by Indian researcher, Shreyas More, Green Charcoal is lightweight and porous, helping to passively regulate the temperature in a building.
Plus, the porous nature of these biological bricks makes them a perfect home for plants and insects, turning our buildings into microhabitats in their own right.
Another exciting development is research into the use of mycelium for building materials. These networks of root-like fibres are best known for producing mushrooms, but their development can be manipulated by humans to create an organic building material that is ideal for insulation, boards, and bricks.
While there’s still work to do before mushroom bricks enter mainstream construction, New York-based design studio, the Living, has already demonstrated its potential.
In 2014, they used mycelium bricks to construct a 13-foot tower, named the Hy-Fi. Used as an event space for 3 months, the building was then taken down and the bricks were composted, proving that it is possible to make a truly biodegradable building.
Mushrooms, hemp, and loofah all show potential in creating the buildings of the future. All three can be grown sustainably, making them a renewable and environmentally friendly resource. However, they do require virgin raw materials, even though they are low impact ones.
That’s not the case for all bio-based building materials. While urine might not be your first choice for your home, it does show real potential as a sustainable construction material.
Reusing a substance that would normally go to waste is at the heart of creating a more sustainable future. So, researchers at the University of Cape Town were thrilled to announce in 2018 that they’d found a way to turn human urine into building bricks.
Once again, the bricks harness the power of bacteria, which are combined with urine and sand to create a solid building block. The process also creates fertiliser as a by-product.
Bio-bricks made using human urine
© University of Cape Town, used under CC BY-ND 4.0, original image.
Reduce, Reuse, Recycle
If you think bricks made from human pee are a revolution too far, the good news is that urine isn’t the only waste material being turned into building supplies.
Food waste is a well-known issue, so construction products that are made using waste food are a way to tackle two problems at the same time.
Researchers at the University of Tokyo are experimenting with using food scraps to create materials that are strong enough to use for construction but remain edible.
Meanwhile, Yorkshire-based company, Chip[s] Board, is already harvesting potato waste and using it to create bioplastics with applications from fashion to construction.
Reusing food waste in buildings is one encouraging trend that could take us a step closer to a circular economy. Another is recycling old plastic to create new buildings, an approach proposed by Newcastle-based designers, E3Design, and their partner, Gary Giles.
Together, E3Design and Giles developed OGEL, which uses recycled plastic to make bricks that can be fitted together without any connectors or joining agents.
Although the bricks still need to be filled with something, this removes the need for cement-based mortar, reducing the carbon footprint of the building while also tackling plastic waste.
Meanwhile, Woodpecker, a company in Bogota, is combining recycled plastic with waste coffee grounds to create a lightweight and strong material that is ideal for prefabricated buildings.
Cigarette butts are another perennial issue that could be addressed through building materials. Research published in 2016 found that baking cigarette butts into clay bricks reduces the energy required to fire the bricks, while also removing the toxic butts from the environment.
Learning from the Past
Exciting new innovations in building materials show potential for addressing waste and creating more sustainable buildings.
However, we shouldn’t ignore the lessons of the past. While many of these new materials aren’t yet widely available, the natural resources used by our ancestors can still help us create more sustainable buildings today.
Before global transport networks turned construction into a worldwide industry, buildings were usually made of whatever materials were easily to hand. Timber, straw, and clay were widely available and easy to work with.
Today, using local construction materials helps to cut down on the environmental impact of transportation. It also honours the spirit of our places, reflecting the unique regional traditions that emerged over time in response to the availability of materials.
Many traditional materials are better for the environment too. Requiring less intensive processing, they have a smaller carbon footprint and are often drawn from renewable sources.
One traditional building material that is enjoying a resurgence in popularity is earth. Earth buildings are known around the world. In the UK alone, we have many different earth walling traditions, including cob from Devon, mud and stud from Lincolnshire, and clay dabbins from Cumbria.
These traditional construction techniques mixed local earth with straw to create thick, sturdy walls. Earth buildings typically have a good thermal mass, meaning they stay warm in winter and cool in summer, requiring less energy to heat.
And what about traditional mortars, renders, and plasters?
We’ve already seen that Portland cement has a high carbon footprint, but cement has only been widely used since the 1800s.
Before that, buildings were made using lime. Both are made from limestone, but lime is a weaker material that doesn’t contain clay.
Don’t assume that weaker means worse, however. Lime was used in buildings for millennia. It hardens slower than cement, but it is also more flexible and less prone to cracking.
From an environmental perspective, lime is often considered a carbon-neutral building material. Although it emits carbon when it is first produced, the lime then reabsorbs carbon dioxide from the atmosphere as it hardens.
Meanwhile, sustainably sourced timber can replace energy-hungry steel or concrete in providing structure to buildings. Our ancestors used timber in their homes, agricultural buildings, and even in their palaces.
Timber is a renewable resource and requires much less carbon dioxide to produce and process than modern alternatives. It also stores carbon, which is only released when the wood is discarded and starts to rot. In a carefully maintained building, the timber can continue to store carbon for many years.
Adopting these historic building materials and combining them with new technologies opens up a new world of sustainable architecture.
Whitford’s Commitment to Sustainable Building Materials
As a sustainable, plastic-free skincare brand, we’re always thrilled to hear of new alternatives to plastic and other environmentally damaging materials.
Our commitment to reducing our impact on the environment extends to the building we use – our London-based studio is an FSC-certified timber-frame unit with a green roof to catch rainwater. It is powered by 100% certified renewable electricity.
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Sources and further reading:
UN Environment Programme, Building sector emissions hit record high, but low-carbon pandemic recovery can help transform sector – UN report
UK Green Building Council, Climate Change
Vandana, M., John, S. E., Maya, K., & Padmalal, D. (2020). Environmental impact of quarrying of building stones and laterite blocks: a comparative study of two river basins in Southern Western Ghats, India. Environmental Earth Sciences, 79(14), 1-15.
Department for Environment, Food, and Rural Affairs, UK Statistics on Waste
The Guardian, Concrete: the most destructive material on Earth
Imperial College London, Best ways to cut carbon emissions from the cement industry explored
Davies, R., Teall, O., Pilegis, M., Kanellopoulos, A., Sharma, T., Jefferson, A., … & Lark, R. (2018). Large scale application of self-healing concrete: Design, construction, and testing. Frontiers in Materials, 5, 51.
The DB Group, CemFree
UK Hempcrete, Hempcrete services from the professionals
Materiability, the Green Charcoal
Bio Based Press, Mycelium as a construction material
The Living, Hy-Fi
University of Cape Town, World-first: Bio-bricks from urine
University of Tokyo, Food scraps get a bold new life
Chip[s] Board, Revolutionary bio-plastics made from food that we leave behind
Woodpecker, What is WPC?
Mohajerani, A., Kadir, A. A., & Larobina, L. (2016). A practical proposal for solving the world’s cigarette butt problem: Recycling in fired clay bricks. Waste management, 52, 228-244.
The Society for the Protection of Ancient Buildings, Unbaked earth walling
Khadka, B. (2020). Rammed earth, as a sustainable and structurally safe green building: a housing solution in the era of global warming and climate change. Asian Journal of Civil Engineering, 21(1), 119-136.
The Society for the Protection of Ancient Buildings, Lime Briefing
British Lime Association, Sustainability: Recabonation
Historic England, Nonsuch Palace, its formal gardens and associated remains, and Cuddington medieval settlement
Puettmann, M., Sinha, A., & Ganguly, I. (2019). Life cycle energy and environmental impacts of cross laminated timber made with coastal Douglas-fir. Journal of Green Building, 14(4), 17-33