Each year, millions of tons of waste are generated by the construction industry – either as byproducts of the creation of new building materials, or through the demolition or refurbishment of existing infrastructure. Thinking outside of the box and finding inventive ways to reuse this waste, or even better, combining these waste products with recyclables from other industries – is one of the most pressing issues we face in designing the cities of tomorrow. Here are a few examples of innovative technologies that are making the construction industry cleaner and more sustainable.
RAP – Recycled Asphalt Pavements
When existing roads require extensive resurfacing or rehabilitation, large quantities of waste asphalt are frequently produced as a result. Ideally, this waste asphalt would then be recycled in the construction of the new roadway – but there are several issues with the conventional manner of accomplishing this.
In order to improve the strength of Recycled Asphalt Pavement (or RAP) to the level required for a new road, milling and processing with added bitumen is necessary. This means the recycled material needs to be hauled off to a processing facility – increasing energy costs, resulting in pollution, and requiring the addition of another raw material, in this case bitumen.
But what if you could use the RAP as is without any additional processing required? This is exactly what innovative geocell technology allowed the Institute of Urban Development of Bogota in Colombia to accomplish. Because geocells provide such efficient lateral confinement, the rutting and deformation which commonly occurs in roads where RAP is used in the base course was no longer a concern.
In addition, the recycled asphalt could be used right there on site, with no processing or additional raw materials required. The project was so successful in fact that the municipal road authority decided to roll out phase II of the program across an additional 50 streets.
Some of the other advantages of using geocells to stabilize RAP for new roadways include faster construction, reduced overall paving thickness resulting in savings across the board, and of course, improved sustainability.
Geocells filled in with recycled asphalt paving (RAP) in Colombia for road resurfacing project
Bottle Bricks
One way the producers of consumable goods can get involved is by designing their products in such a way that people can make use of the packaging long after they’ve finished with its contents. Heineken’s bottle brick project in the Caribbean is a shining example. By changing the shape of their beer bottles slightly, they were able to produce a product that could easily be reused in the production of affordable housing. Each bottleneck slots into the base of its partner, creating a strong interlocking line that’s also easy to assemble. And as an added benefit for the company, the tessellating design also made the bottles easier and more efficient for them to transport when full.
Composite Lumber made from wood and recycled plastic
Finding ways to deal with the enormous amount of plastic waste generated across the globe is one of the most pressing environmental challenges of our time, as the consequences of improperly managed plastic waste can have detrimental impacts for centuries to come. But by incorporating waste plastic into objects which are designed to last for a long time, we can actually make use of its innate durability. One such product which is gaining in popularity is composite lumber. Made from renewable materials like wood or even wheat straw combined with recycled plastic, a strong yet lightweight lumber product can be produced – ideal for use in fencing, decking and retaining walls.
Insulation made from recycled glass
In the UK, one company is demonstrating that recycled materials don’t have to be just one component of a new building material but can actually make up the majority of its content. Their innovative wall insulation solution known as Superwall 36 is made from up to 84% recycled glass – which has the advantage of also being entirely non-combustible. Making use of a product like this, which also helps to make a building more energy efficient, is an excellent way to reduce the overall environmental footprint of a new or retrofitted building.
Strategies for success
Actually, applying these kinds of materials on a larger scale might call for some sweeping changes, but there is huge scope for improvement. By planning each new project in such a way that waste is minimalized, proper demolition protocols are followed, alternative recycled materials and new technologies are given due consideration, reusable materials are reclaimed wherever possible and that a careful audit process is followed during the design stage; money and time can be saved, while also minimizing environmental impact.