In a world grappling with the consequences of traditional construction methods, a compelling innovation in eco-friendly materials and technologies emerges. These new sustainable trends help redefine the structural landscape while contributing to a greener, more sustainable tomorrow.

In the realm of sustainable construction, innovation and environmental consciousness converge to shape the future of building practices.

This article will delve into the revolution of eco-friendly materials, exploring green alternatives to traditional methods and case studies from around the globe.

Construction is a resource-intensive activity. Humans have been innovating ways of building their houses for millennia.

But as we all know, with the Industrial Revolution and demographic explosion, economies turned to prioritizing the extraction, production, and transportation of raw materials.

The way we have built for decades is not viable in the long term. We continue to depend on extracting natural resources to create materials that end up in landfills or polluting nature after fulfilling their function.

Using construction materials, such as concrete and steel, requires large amounts of energy and water, generating greenhouse gas emissions.

For example, the production of cement, which is essential for mixing concrete, is responsible for 7% of global CO2 emissions (each pound of cement releases almost another pound of carbon dioxide). Steel, for its part, is responsible for 8% of global CO2 emissions.

In response to growing concern for the environment, there has been a rise in green building materials as they have a lower environmental impact.

Bamboo is a renewable and sustainable material that can be used to make different construction products, such as beams, panels, tiles, and bricks. It can also be used to build complete structures in homes, schools, and offices.

The success of the use of bamboo depends a lot on whether it is used appropriately. It must have the correct preservation treatment, curing, correct design, and qualified labor for fundamental activities such as assembly, treatments, etc., as well as the place and permits where the project is being executed.

 2-Benefits of Bamboo

Bamboo has many advantageous properties for construction.

• Resistance: Bamboo is strong and resistant. It can be used to build structures that require high strength, such as bridges and buildings.

• Lightweight: Bamboo makes handling and transportation easier.

• Durability: Bamboo can last for centuries with proper care.

• Thermal insulation: Bamboo is a good thermal insulator, which can help reduce heating and cooling costs.

In Europe, more than a third of the waste generated is CDEW (construction, demolition, and excavation waste). In the UK, the amount of CDEW generated annually is around 120 million metric tons.

The term "recycled concrete" means the rubble itself, also called construction, demolition, and excavation waste (CDEW), can be converted into materials available for construction.

Concrete is broken, and impurities such as earth or steel are removed and crushed until the desired size is obtained. This process can be carried out in a quarry or in the same place where the concrete is located. The resulting material, called recycled concrete aggregate (RCA), can be used to make new concrete products.

In addition to making concrete, they are also used to make materials such as bricks or asphalt agglomerates.

This process reduces the consumption of resources and prevents waste from ending up in landfills or contaminating rivers and soils. It can also save on high costs related to landfill disposal fees, and being lighter than traditional concrete means more volume per ton per order.

Recycled plastic can be used to make a variety of construction products, such as bricks, tiles, pipes, and panels. It can also be used to make recycled concrete, which is a more sustainable alternative to traditional concrete.

Recycled plastic has several advantages over traditional building materials.

• Lightness: Recycled plastic is lighter than wood, concrete, and metal.

• Energy efficiency: Producing recycled plastic requires less mechanical equipment, machinery, and labor, which increases the speed of construction.

• Flexibility: Recycled plastic can be easily molded into any shape on an industrial scale compared to metal and wood, making it suitable for multiple tasks, from concreting and water infiltration to grass protection.

It is possible to use recycled plastic in the interior architectural elements of homes, considering that it does not support significant loads unless combined with other materials.

Cross-laminated timber (CLT) stands out as a structural board composed of layers of wood arranged at right angles, providing rigidity, homogeneity, and resistance.

Its versatility in construction, especially in large-scale projects, is due to its ability to withstand significant loads, being cost-effective, easy to handle, and lighter than traditional steel and concrete.

In addition to its thermal and acoustic properties, CLT is efficient during construction, generating little waste and allowing rapid assembly.

This material also stands out for its fire resistance and anti-seismic capacity, helping to reduce construction costs and time.

In aesthetic terms, CLT offers a warm and attractive appearance, fulfilling structural and cladding functions in a single solid panel, such as exterior and interior load-bearing walls, shear walls, slabs, and roofs.

Beyond its structural capacity, wood stands out as a valuable resource for ornamental purposes. Its warmth, texture, and variety of tones make it popular for interior and exterior coverings, as well as floors and platforms.

Hemp is one of the oldest plants used by humans. Its seeds and flowers are used to make healthy foods, medicines, and organic beauty products. Paper, clothing, and biofuel are made with its stems and fibers.

Currently, the waste fibers, called hemp chips, are used to manufacture hempcrete.

Hempcrete is a biocomposite material made by mixing hemp chips with lime and water, forming a type of aggregate concrete.

Hemp chips have a high silica content, allowing them to adhere consistently to lime. Once cast, hempcrete requires much less water than traditional cement in its curing process.

The lime and water act as a binder that allows the mixture to be molded into blocks and panels or applied directly as wet fill material.

 Additionally, hempcrete can be combined with other construction elements to form floors and

roofs, providing an insulating structure.

Being a light material, it is not ideal for supporting large loads. It makes it a material that is not very suitable for structural use (foundations or bases), so its use is more widespread in single-story constructions.

Due to its low thermal conductivity and wind resistance, it is an excellent alternative as a thermal insulator in the form of plates or panels.

It is very resistant to impacts. The air pockets forming between its particles make it earthquake-resistant. Therefore, it can be beneficial in seismic areas.

1- Mexico: Photocatalytic and Permeable Concrete

The National Autonomous University of Mexico (UNAM) has developed two types of ecological concrete that could help reduce the environmental impact of construction.

The first type of concrete, called photocatalytic, absorbs carbon dioxide (CO2) from the air and converts it into inert compounds. The second type, called permeable, helps purify rainwater.

Photocatalytic concrete uses a substance called titanium dioxide (TiO2) that, when exposed to sunlight, reacts with CO2 in the air to form calcium carbonate (CaCO3). CaCO3 is an inert compound that does not contribute to climate change.

Permeable concrete has a porous structure that allows rainwater to penetrate inside. Rainwater seeps through concrete, carrying contaminants such as heavy metals and organic matter.

In one study, UNAM researchers used photocatalytic concrete to build a 65-foot-long wall. The wall absorbed 220 pounds of CO2 in one year, equivalent to the emissions from a car's exhaust pipe for about 65 miles.

The researchers also used permeable concrete to build a 10-square-foot roof. The roof collected and purified 26 gallons of rainwater in one year.

These green materials are still in development, but they have the potential to revolutionize sustainable construction.

The American company Heirloom Carbon Technologies developed a new concrete that captures carbon dioxide (CO2) from the air. This concrete, called CarbonCure, is made by adding a chemical agent to cement that reacts with CO2 to form solid compounds.

One block of this concrete captured 66 pounds of CO2. It is equivalent to the tailpipe emissions of driving about 74 miles in a car.

However, CarbonCure is still in development, and some challenges need to be addressed before it is commercially available. For example, the cost of CarbonCure is even higher than that of traditional concrete.

Further testing is necessary to determine the long-term effectiveness of Carbon Cure.

Despite these challenges, Carbon Cure has the potential to be an important technology for reducing CO2 emissions from construction.

Brock Commons Tall Wood House, a student residence at the University of British Columbia located in Vancouver (Canada), designed by the architectural firm Acton Ostry Architects Inc., holds the title of the tallest building with a hybrid wood structure in the world.

It can accommodate 404 students in bedrooms, studies, and modern social areas, has 18 floors, a height of 173 feet, and was structurally and entirely armed with CLT panels, later covered with plaster and concrete.

The Mjostarnet Building, opened in March 2019, faces the largest lake in Norway and has a height of 280 meters. They used cross-laminated wood for stairs, elevator shafts, and balconies. Therefore, it is considered the tallest construction in the world, entirely designed in wood.

This construction includes apartments, a restaurant, offices, a swimming pool, and other common areas.

Spain has one of the largest wooden structures in the world: the “Setas de Sevilla,” or Metropol Parasol.

 Designed by German architect Jürgen Mayer, this surprising structure is eye-catching for tourists. The use of laminated wood in its construction shows the promising role of wood in contemporary architecture.

Wood provides calm and connection with nature in built spaces. In addition, technology allows you to create designs and patterns with wood, generating visually attractive environments.

The hempcrete revolution as a sustainable material in construction gained momentum when the first hempcrete house was built in North Carolina.

Other countries, such as India, Israel, Nepal, New Zealand, Australia, Canada, the United Kingdom, and Mexico, are also embracing this eco-friendly solution. Companies such as GoHemp in India, IsoHemp in Belgium, Hemptecture in Washington (USA), Left Hand Hemp in Colorado (USA), Hempcrete Spain in Spain, and HempMeds in Mexico are leading the way in a market with enormous potential for growth and profitability.

The application of wood products from countries located many miles away is not convenient because it distorts the ecological and sustainability reasons for using wood. Long distances begin to penalize the material due to its carbon footprint. Therefore, the strategic distribution of companies is also a fundamental aspect.

According to experts, with sustainably managed forests, the wood requirements for sustainable construction should not worry us.

Bioconstruction makes it possible to reduce CO2 emissions associated with buildings and improve habitability.

Examples around the world of the use of eco-friendly materials in construction (hempcrete, wood, bio-aggregate concrete, etc.) show that it is worth investing in sustainable strategies.

The factors to overcome to promote eco-friendly materials in construction are a lack of competition, associated with ignorance of the techniques and their significance.

In summary, sustainable construction offers a vital solution for more environmentally friendly practices. Materials such as bamboo, recycled concrete, recycled plastic, cross-laminated timber, and hempcrete are proving to be viable options with lower environmental impact.

The construction industry has evolved, introducing innovations and technologies that seek to reduce carbon emissions associated with construction. This evolution shows a growing demand for and interest in eco-friendly construction materials.

 Case studies globally, from the National Autonomous University of Mexico to buildings in Canada and Norway, succeeded in using these materials. They are effective not only in terms of sustainability but also in the creation of functional and aesthetically attractive structures.

The challenge lies in overcoming the lack of knowledge and competence surrounding these technologies. By adopting these eco-friendly materials, we contribute to preserving natural resources while creating functional buildings.

Investing in sustainable strategies is a decision that makes sense, not only from an ecological perspective but also from a practical and aesthetic perspective.