Beating plastic pollution in construction

For decades, plastic pollution has seeped into every corner of the world, leaching into the water we drink, the food we eat, and even our bodies, and exacerbating the triple planetary crisis of climate change, nature loss, and pollution. 

The focus for concern has tended to be on single-use plastics from the packaging industry, but the construction industry is a significant user of plastics too, and there is no sign of the appetite for these materials abating in a sector which is the second largest end-user globally.

This year World Environment Day joins the United Nations Environment Programme-led campaign #BeatPlasticPollution to mobilise communities worldwide to implement and advocate for solutions. World Environment Day spotlights the growing scientific evidence on the impacts of plastic pollution and drives momentum to refuse, reduce, reuse, recycle, and rethink plastics use. It will also reinforce the global commitment made in 2022 to end plastic pollution through a global plastic pollution treaty. 

This gives us an opportunity to reflect on the volumes and types of plastics used in construction, their applications, lifespans, and how they are managed at end of life, as well as potential for using recycled plastics or alternatives and considering how this all fits in with a circular economy.

Plastic use in construction 

Plastics are used in numerous long-lasting and medium-term applications across residential and commercial projects, including windows, doors, and frames, plumbing and electrical applications such as pipes and cables, insulation, roofing, cladding and membranes, formwork and barriers for temporary construction, flooring and interior finishes, paints, sanitaryware, and furniture, as well as single-use plastics such as material and product packaging and disposable items used on site.

According to ResearchAndMarkets.com, the global market for Construction Plastics was estimated at US$112.3 Billion in 2023 and is projected to reach US$187.1 Billion by 2030. These plastics include PVC (polyvinyl chloride), HDPE (high-density polyethylene), polystyrene, and polycarbonate, each engineered for specific properties like strength, insulation, and weather resistance.

Finding alternatives

Construction plastics are durable and lightweight, cost-effective, and resistant to corrosion, moisture, and chemicals, making them ideal for various applications and in modern construction they are commonplace.

Innovations in bio-based (derived from plants, fungi, and organic waste) plastics and growth in the use of recycled plastics are gaining traction, allowing manufacturers to reduce dependence on virgin materials, but challenges remain, including the difficulty of recycling certain types of plastics and the need for further research and development to improve the durability and performance of some recycled plastic building materials.

The environmental cost of plastic production and plastic waste, along with concerns about the potential public health implications of widespread use of additives in these materials, has led to calls to limit the use of construction plastics and explore alternatives. But it is difficult to see the use of many plastic items slowing, without significant investment in the promotion of alternatives.

Innovations 

Towards the end of last year, Habitable (a US-based nonprofit focused on sustainability in buildings and construction) and the architectural firm Perkins & Will released two reports on plastic building materials and alternatives, aimed at sparking discussion and action across the industry about what they called the hidden plastics problem in buildings. 

They highlighted that demand for plastic building materials is projected to almost double by 2050, that building and construction accounts for 70% of PVC use, that 18% of microplastics in the ocean come from paints applied to buildings, and in the US alone 1.1 million tons of plastic from carpet is discarded annually.

Habitable and the U.S. Green Building Council are currently piloting an Informed Product Guidance tool for materials selection that steers builders away from plastics towards traditional materials, like wood floors and lime-based paints, along with newer plant-based materials, such as cork flooring and pressed paperboard materials, that are emerging as alternatives to PVC floors and polystyrene insulation.

They are encouraging companies to select building materials based on their full life cycle and engage with their supply chain to explore the availability, cost and performance of non-plastic materials.

In Canada, Light House launched a Construction Plastics Initiative aimed at diverting and upcycling plastic waste from 10 Metro Vancouver construction sites in a pilot project set to last until February 2026. 

They highlight that studies from Europe estimate that approximately 80% of the plastic waste from on-site construction activities is clean packaging and can be easily diverted. The remainder comes from excess product, offcuts and wastage of plastic building products, including some hard-to-manage plastics. 

The project aims to move away from a linear model (take, make, dispose) towards a circular model which sees plastic waste as a resource that can be preserved and repurposed. 

Plastics generated on site are kept separate from other construction materials and sent to a plastics processor where they are extruded into a plastic pellet which is then sold to a local plastics manufacturer that blends the pellets with other resins to manufacture a proprietary building product used in concrete slab floors in multi-unit residential buildings. This displaces concrete in the slab, reducing the amount of concrete required and reducing the weight of the floor, which reduces the size and material requirements for load bearing supports. 

Incorporating repurposed construction plastics in this product reduces the amount of virgin plastic required – a central objective of a circular economy – and transforms waste plastic into a valuable material resource in the manufacturing process.

Initiatives like this are heartening, but they may face a tall order to halt the growth in construction plastics, as lack of alternatives, resistance to change, supply chain complexities and regulatory barriers to adoption of alternative materials all come into play. But with innovation and a circular mindset, solutions can be found. With the scale and projected growth in global construction plastic use, this is likely to be a topic that requires much more focus in future.