Concrete is far and away the most common building material worldwide. Around 10 billion tonnes are produced each year, meaning it is literally the building blocks of towns and cities all over the world. However, this convenience comes at an environmental cost. Concrete production is the second largest industrial source of CO2 emissions in the world and consumes large volumes of natural resources such as water and sand. But, if concrete isn’t as sustainable as we’d like, what other materials could be used in its place to help build a more sustainable future?
1. Hempcrete
Hempcrete is growing in popularity as an alternative to concrete. Bio-based, it is made from hemp, lime and water and is supremely sustainable. In fact, it’s a better-than-zero carbon product because hemp absorbs such large volumes of CO2 as it grows. Even factoring in the emissions resulting from production, transportation, and the construction process, it remains a highly desirable low carbon product.
Another big plus for hempcrete is its incredible thermal and insulating properties, meaning overall energy use is reduced during the building’s lifespan.
2. Bamboo
Bamboo is another incredibly sustainable, natural material. It has tensile and compressive strength comparable with steel and concrete respectively, making it suitable for a range of applications. It’s also incredibly fast to grow, requires little energy to do so and traps a good amount of CO2. Lightweight, bamboo is additionally naturally resistant to many pests and diseases, making it long lasting and durable.
3. Cork
Much like bamboo, cork is a natural material that grows incredibly quickly. It’s durable and flexible, making it a versatile addition to many construction projects.
Once harvested, cork can be used in several ways. It’s common to see cork used in tiles (both wall and floor) for example, but it’s also a great natural insulator, highly resistant to fire and doesn’t rot. It can additionally be used to absorb sound, so is useful in buildings where soundproofing is required, for example in multi-tenant housing or commercial office spaces.
4. Green Leaf Brick
Green Leaf Bricks are made entirely from waste materials which would otherwise end up in landfill. There are several companies and organisations experimenting with this type of 100% recycled brick, including one initiative in the Netherlands which has created a load bearing brick made entirely of plastic waste. Other Green Leaf bricks use a range of waste materials, including recycled glass, ceramic scraps and even sewage waste, often rescued from landfill, to create new fired masonry bricks. These types of bricks are robust and long lasting, non-flammable and have a high level of compressive strength.
5. Mycelium
Mushrooms are an unlikely choice for a construction material but Mycelium, formed from the root structure of fungi, can be made into bricks when mixed with sawdust. These bricks are strong, sturdy, and lightweight and can be formed into unique shapes for unusual building designs. Organic and compostable, Mycelium can also replace traditional insultation materials as it stands up well to high temperatures.
