For decades, copper tubing has been a common plumbing and piping material in use across the United States, and it continues to be a popular material to this day. For this reason, many of our customers want to know if POLYMELT’s PP-R piping systems can be combined or joined with copper tubing and piping.

The short and simple answer is yes! POLYMELT offers special connections that allow our PP-R pipes and fittings to be joined to copper tubing systems, and POLYMELT PP-R pipes are in use in combination with copper around the world. However, copper and PP-R are very different materials with some dissimilar attributes. This poses some challenges that must be accounted for before installation to ensure that a combined copper and PP-R piping system works as intended.

Most importantly, super-smooth PP-R pipes have a higher flow velocity than copper pipes. In mixed-material plumbing systems that combine copper with PP-R piping materials, it is critically important to limit flow velocities through each copper component to ensure that flow-accelerated corrosion of these copper components will not occur. The maximum flow velocities for the specific water temperature and water chemistry of the system (as published by the Copper Development Association) must be adhered to. This is important for the longevity of both the copper and the PP-R piping materials in your piping system.

Typically, a piping system that is constructed utilizing only PP-R materials will not suffer from flow-accelerated copper corrosion. Therefore, when adequate control of water chemistry, water velocities, or water temperatures cannot be assured over the lifetime of the plumbing system, we naturally recommend to avoiding mixed-material piping systems by utilizing only POLYMELT PP-R materials, or other approved polymer materials, in place of copper tubing and fittings.

If you have questions about how POLYMELT PP-R pipe might fit with copper tubing in your project, contact us today for a free consultation. Our piping experts can assist you in planning your project so that it lasts for decades.