The global urban population is projected to increase by 57% to 2.4 billion in the next 30 years – and material consumption is predicted to grow even faster. Without a new approach, the high demand for raw materials far exceeds what the planet can sustainably provide. A promising opportunity for reducing carbon emissions in the built environment and infrastructure is incorporating the principles of the circular economy into all phases of a building’s cycle, which can help meet the needs of the built space while contributing to the goal of carbon neutrality.

By Serge Salat

Circular economy approaches in buildings are needed to reduce the embodied emissions of the built environment. These include:

• designing buildings to be adaptable and easy to disassemble at the end of their life;
• using innovative products and technologies to make buildings more circular;
• designing buildings to be reused and refurbished instead of demolished;
• allowing maximum reuse of materials when deconstructing buildings;
• using innovative business models enabling more flexible use of existing and new buildings, and therefore more efficient performance; and
• planning sustainable infrastructure that can adapt over time.

Highest value for as long as possible

We need to define a hierarchy for building approaches that maximizes the use of existing materials with the aim of retaining existing buildings. A circular economy approach in the built environment keeps buildings, products, and materials at their highest value for as long as possible. The pathway toward a circular economy requires spatial planning strategies to foster integrative flows of resources, including energy.

In London, for example, the principles of the circular economy were incorporated into the draft plan for the regeneration project of the Old Oak and Park Royal development. The plan aims to create more than 25,500 new homes and 65,000 jobs on 640 hectares of residential and industrial areas while ensuring optimal circulation of local materials. The main opportunity identified is the ability to reuse and disassemble buildings and infrastructure. By capturing local resources such as water, heat, organic matter, and solid waste for reuse and allocating underutilized areas for agriculture, the plan aims to ensure the environmental and economic resilience of the area.

Cities accelerating the pace of change at scale

Forward-looking cities are already accelerating the transition to a fully circular economy. London, Amsterdam, Barcelona, Copenhagen, Paris, and Phoenix have published road maps for circular economies and have begun to put in place the necessary policies, partnerships, and infrastructure. This approach will become crucial in the coming decades for all cities.

Re-materializing Construction

This text is based on the paper How the Circular Economy Can Lead to Carbon Neutrality presented by Serge Salat at the LafargeHolcim Forum “Re-materializing Construction” held at the American University in Cairo, Egypt.

How the Circular Economy Can Lead to Carbon Neutrality

Inspired by the discussions by 350 leading thinkers from architecture, engineering, planning, and the construction industry from 55 countries, Ruby Press Berlin has published The Materials Book that evaluates current architectural practices and models, and introduces materials and methods to maximize the environmental, social, and economic performance of the built environment in the context of “Re-materializing Construction”.

The Materials Book: Re-materializing Construction – Cairo (Ruby Press)