The construction industry accounts for a significant amount of energy use and greenhouse gas emissions. That’s why it’s important to choose sustainable building materials.
Reusing and recycling materials has long been a key tenet of sustainability. Jimmy used salvaged materials in the Kendeda Building for Innovative Sustainable Design at Georgia Tech, including reclaimed wood and old slate shingles.
Bamboo
Bamboo is an excellent sustainable building material, as it grows quickly and is often locally available. It is also much lighter than steel, reducing the carbon footprint associated with transportation. Bamboo can be used in construction, scaffolding, and for rugs, among other uses. It is a strong and durable material that can replace hardwood timber, which is great for reducing pressure on natural forests.
Some bamboo species grow in clumps, making them ideal for tropical planting schemes, while others work well as natural screening and are also good for creating architectural features. In addition, the raw materials can be recycled to create new bamboos, reducing waste and making it a more environmentally friendly alternative to wood.
Straw bale construction is an eco-friendly building technique that uses straw to insulate walls in a home or other structure. It is resistant to fire, pests and mold, and has a low environmental impact. Rammed earth is another eco-friendly building method that involves compressing a mixture of soil, clay and natural fibers into sturdy forms to build walls. It is a cost-effective and energy-efficient option for green buildings, and is also known for its thermal mass, which helps regulate indoor temperatures and reduce energy consumption.
Plastic
Plastic isn’t usually associated with sustainable construction, but this material can be an eco-friendly option. For example, recycled plastic can be used to insulate walls and roofs. This helps reduce energy consumption and cut building costs. It also prevents the waste of valuable resources and keeps plastic out of landfills.
Another way that plastic contributes to sustainability is its lightweight properties. It allows structures to be built with less concrete, reducing embodied energy. It can also be used to create components for wind and solar power, helping to generate renewable green energy.
Paper is a common sustainable building material, and innovations like Newspaper Wood help to reuse paper rather than sending it to the landfill. It can be used to insulate buildings, and it is also fire-resistant and pest-resistant.
Many of these sustainable materials are made from recycled products, and they can be combined with traditional building materials to provide a more eco-friendly structure. These materials can also save on energy bills and improve indoor air quality. They may also be sourced locally, which helps to reduce transportation-related emissions and support local economies.
Recycled Materials
The sustainable materials market is growing quickly as an effort to protect the environment and reduce energy-efficiency and building operation costs. It’s also an opportunity to give discarded items a new life instead of sending them to landfills or polluting waterways.
Using recycled materials like aggregates (rock, sand or gravel) and metals from old electronics and appliances can greatly reduce the ecological footprint of a new construction project. Recyclable paper, wood, plastic, textiles, tyres and even organic waste can be transformed into high-quality building products.
Bamboo can be woven to form flooring, walls and counters for a stylish and durable finish that’s also eco-friendly. It’s an excellent insulator and has natural resistance to mold and pests. It also adsorbs carbon dioxide, making it one of the most beneficial plants to grow around the world.
Sheep’s wool is another sustainable and renewable insulation material that doesn’t require harming animals. It’s also fire-resistant and can wick moisture to prevent rot. Cork, harvested from the bark of a cork oak tree, is becoming popular in North America for use as a non-toxic and hypoallergenic insulation material.
Rammed Earth
Rammed earth, also known as taipa, is an ancient construction technique that involves compacting soil and occasionally straw into forms, resulting in thick, durable walls. The walls are load-bearing, fireproof, and resistant to termite damage. They’re also insulating, helping to regulate internal temperatures and reducing energy usage.
Because the material is natural and local, rammed earth buildings are often considered more sustainable than those constructed with other materials. However, the process can be labor-intensive and require specialized skills to construct. In addition, the walls are usually stabilized with cement which can have a high embodied carbon footprint. Research is ongoing into alternative binders like natural pozzolans or blast-furnace slag that could reduce reliance on cement and lower the embodied carbon of the walls.
Stabilized rammed earth walls have good compressive strength, meaning openings can be made without lintels. They’re also inherently fire-resistant, but should be well insulated and designed to provide moisture resistance. Since the walls can be very porous, they’re prone to weather erosion, but can be addressed through design detailing such as long overhanging eaves and raised plinths.
Martian Concrete
There’s been a lot of hype lately about sending humans to Mars. From the non-profit Mars One’s plans to establish the first human settlement in 2025 to this year’s Golden Globe nominee The Martian, it seems like this sci-fi fantasy might soon become a reality. In order to make this happen, we’ll need the ability to build structures in space. A team of Northwestern Engineering scientists led by Lin Wan, Roman Wendner and Gianluca Cusatis may have found a solution. Their construction material, dubbed StarCrete, combines the elements of Mars to create buildings that can withstand the harsh conditions on the red planet.
Similar to concrete made on Earth, this sustainable building material consists of an aggregate and a binding agent. Instead of the gravel, cement and water used in regular concrete though, this building material uses simulated Martian soil and molten sulphur.
To create the concrete, researchers heated sulphur to its liquid state and then mixed it with a granular Martian soil simulant that was sieved to a maximum size of 1 mm. Tests showed that the resulting sulfur concrete has unconfined compression strength, flexural strength and splitting tensile strength comparable to cementitious concrete. Moreover, it requires less energy to form, cures in a much shorter period of time and is highly resistant to acid and salt environments.