Towards a circular Construction sector
Buildings and infrastructure are seen as the face of ‘development’. The rising skyscrapers tell us we are achieving new heights every day, but are we really?
Under the present linear model, the construction and demolition of buildings consumes 42 billion tonnes of resources annually, accounting for around one-third of global material consumption and waste generation, making it the most material-intensive sector. To make matters worse, 11% of global energy related CO2 emissions can be attributed to the construction industry. However, in recent years, a paradigm shift has occurred in the industry due to the pressure of external factors such as climate change and scarcity of natural resources. Nations across the world are looking for methods to adopt the Circular Economy model, that aims at keeping the materials in a closed loop to retain their maximum value, and therefore reducing the waste generation and resource extraction. The question that arises is, how do we change the linear economy to one that is circular?
The building blocks
Design the building in a way that it’s easily dismantlable, adaptable, durable and can be reused for different purposes. Opt for sustainable construction methods and building materials that take the ecological structure into account. Example: 3D printing of building units on- or- off site, from components to entire buildings, can minimise waste generation and resource consumption.
Suppliers can offer bio based materials and ensure that building materials of the highest possible grade are retained and reused.
Building information modelling (BIM) and similar digital building mapping technology can help turn buildings into ‘banks of material’. These digital material passports can disclose what materials and components are in the building, where they are sourced from, and guidance on their potential future use. This makes reusing building components and recycling materials significantly easier.
Policy and legal intervention by the government through fiscal measures, such as landfill taxes, incentivization of circular models, regulation on material management etc., can encourage builders to go circular.
The future is now
Circular Economy is no more just a vision for the future, but a need and necessity of the present, and many companies are already closing the loop. To understand the practical application, here is a case study of the Venlo City Hall in the Netherlands, that has a Cradle to Cradle design.
The hall is built on the edge of the River Meuse in an area that would benefit from regeneration and economic development. It’s facade comprises over 100 plant varieties that convert carbon dioxide to oxygen, filter particulates, provide a level of noise insulation, and create a habitat for birds and insects.
It has solar panels that provide power and shade. Two solar chimneys also passively heat and cool the building. Rainwater is collected on the roof, which is then filtered for flushing toilets. The components in the building are documented in a digital material passport, thereby recouping a proportion of the original investment. Similarly, the furniture in the building is under a ‘buy and buy-back’ arrangement and is easy to disassemble for maintenance, ensuring workable components can be reused.
While the road to a circular construction sector has a lot of challenges to overcome, with effective and comprehensive collaborations between designers, scientists, policymakers, companies, and most importantly the consumers, the goal is not impossible.
The fruits of these efforts will be borne in increased employment and resource efficiency, reduced waste and emissions, and economic growth, thus leading to a sustainable and bright future.