February 12, 2025
Understanding the Sustainability Benefits of PEX Piping Systems
By Chrissie Walsh and Alex Gross
Every year, the building industry is increasing PEX pipe usage due to its wide range of diameters, installation ease, and long-lasting performance. Additionally, the corrosion resistance, resilience in freeze/thaw cycles, and superior flow properties further underscore why more engineers are specifying the product and more contractors are installing it.
However, what is less known in the industry is how the standard characteristics of PEX piping systems directly correlate to increased sustainability for a project.
The details below outline key facts that reveal why PEX piping systems are becoming an increasingly popular choice for a variety of applications.
Differentiation from single-use plastics: The material in PEX is not the same as single-use plastics that are causing environmental issues worldwide. PEX pipes are designed and manufactured to last for decades behind walls, under floors, or in the ground. And when they do reach their end of life, PEX pipes can be recycled using advancing technologies, helping contribute to a circular economy.
Lower carbon footprint: Reference studies show that PEX pipes have a lower carbon footprint than other piping materials when considering their whole lifecycle. These studies take raw material extraction, manufacturing, transformation into products, transportation costs, installation, lifetime of use, and disposal or transformation into other products at the end of life, into account to accurately assess the complete carbon footprint. Overall, PEX pipe has 25% lower total greenhouse gas emissions and 3% lower climate change impact compared to metallics. Visit the TEPPFA website to see the environmental footprint of polymer piping systems.
Product transparency: Environmental Product Declarations (EPDs) reveal a product’s environmental impact throughout its lifecycle and shed light on how products exist in the world. Many PEX pipe manufacturers value sustainability and aim to provide data-driven transparency on their product offering with the intention of creating informed decisions focused on embodied carbon and sustainable action. In fact, GF Building Flow Solutions is leading the way with a goal of 90% product by sales coverage in EPDs.
Resilient strength: The flexibility and elasticity of PEX pipes is highly beneficial in applications where the product is buried underground or may be subject to temporary freezing conditions. The Plastics Pipe Institute (PPI) Technical Report (TR-52) proves the exceptional resiliency of PEX pipe in freeze/thaw cycles. This flexibility and resilient strength help reduce the risk of system damage, repipes, and unnecessary product waste.
Better hygiene: The smooth inner surface of PEX pipes minimizes friction loss and promotes higher flow with less opportunity for stagnation and bacterial growth. This, in turn, provides better system hygiene and can have a direct impact on reduced instances of legionella and other human health threats.
Fewer joints: Flexible PEX pipes are available in long, continuous coils, allowing fewer necessary joints in a system and less opportunity for infiltration into the network or exfiltration into surrounding soils. Fewer joints also mean less material usage, improved cost savings, and less embodied carbon being attributed to the project.
Jobsite safety: Compared to metals, the lighter weight of PEX pipes requires less strain on the body, and the connection system eliminates the dangers of open flame. Add to those benefits the reality that there are fewer skilled workers in the trades, which means a faster, easier system to install will help alleviate those skilled-labor challenges.
Application options: With sizes available up to 3" in diameter, there are numerous opportunities for PEX piping systems in various plumbing, hydronics, and radiant heating and cooling projects. And because water has the capacity to transport energy 3,500 times greater than air, heating and cooling with water in a hydronics or radiant application is a much more energy-efficient solution compared to a traditional HVAC system. Radiant and hydronics systems also integrate with sustainable building technologies, such as solar and heat pumps, to offer an even better solution for indoor comfort. In addition, durable PEX pipes are ideal for prefabrication applications, minimizing the number of skilled trades on the jobsite.
Sustainability credentials: The Climate Impact of Plastics by McKinsey and Company, and research conducted by Environmental Science & Technology prove that replacing alternative materials, such as copper, with PEX piping systems is beneficial because polymers generate less greenhouse gas emissions throughout their lifecycle. Additionally, PEX piping systems can be recycled when scrapped or at the end their life, with advancing technological capacities continuing to scale towards landfill avoidance. A series of independent studies by the Flemish Institute for Technological Research (VITO) measured the environmental footprint of various types of polymer piping systems, based on a full lifecycle assessment.
Conclusion
With strong performance, low environmental impact, and decades of reliable service, PEX piping systems are ideal in various applications and are increasingly being specified at larger diameters for plumbing and hydronics. As the building industry evolves and develops more integrated systems thinking during the design process, including decarbonization, maximized energy efficiency, and optimized water usage, PEX piping systems will continue to expand across the industry to provide buildings with more sustainable, efficient solutions.
References and Additional Resources