CPVC Piping Systems

Don’t be Misled by False Claims Made by Manufacturers of PP-R Pipe and Fittings

Don’t be Misled by False Claims Made by ManufacturersWithin the past year, there has been a major push by manufacturers of polypropylene (PP-R) pipe and fittings to gain market share in the United States by making unsubstantiated claims regarding the products’ overall performance. Before deciding whether PP-R makes sense for your next project, consider the following facts and how they compare with the proven performance of FlowGuard Gold® and Corzan® CPVC. 

  • PP-R is not included in most model plumbing codes. In fact, several forms of PP-R piping cannot even achieve the important NSF 61 certification for potable water systems. 
  • PP-R can only handle half the pressure of comparably sized CPVC pipe. To compensate for the difference in pressure, most PP-R pipe and fittings are thicker. 
  • PP-R is not rated to temperatures in excess of 170° without the use of reinforcing fiberglass. Unfortunately, the addition of the fiberglass layer creates a number of challenges, especially once the protective inner wall erodes away. 
  • Unlike CPVC, which has a proven track record that dates back more than 50 years, PP-R has only been used in plumbing applications since the 1990s. 
  • Whereas CPVC is approved for use in even the most highly chlorinated municipal water systems, PP-R water heater dip tubes experienced massive failures in the 1990s as a result of exposure to hot chlorinated water. That’s why, even today, PP-R is unacceptable for hot water systems. When tested in accordance with the industry’s premier NSF-P171 Protocol for Chlorine Resistance of Plastic Piping Materials, PP-R has been shown to degrade by up to 50 percent in hot, chlorinated water. 
  • PP-R pipe and fittings are joined via a labor-intensive heat fusion process and very expensive tool costs that requires an electrical source and an expensive welding machine for each worker on the jobsite. The welding tool heats up to 500° F, creating a burn hazard and adding time to the installation process to allow the device to heat up and cool down. The process also requires a large amount of space to work and creates an unacceptable margin for installer error. 
  • Despite the fact that various manufacturers have touted the “green” advantages of PP-R, the reality is that the use of PP-R does not yield any LEED credits or points. In addition, since most PP-R pipe requires the addition of a fiberglass layer to increase its strength such that it’s comparable to CPVC, PP-R used for hot water applications cannot be recycled. 
  • Multiple international studies document that PP-R is much more susceptible to the formation of biofilm than CPVC. One study, in fact, conducted by a leading water research institute in 2007 confirmed that the potential for biofilm to form on PP-R is three times higher than what it is for CPVC, making PP-R one of the most biofilm-prone piping materials studied. While piping system design influences biofilm formation more than the piping material itself, designers can be sure that using CPVC is a safer choice than PP-R. 
  • Unlike CPVC, which is fire retardant and will not sustain a flame, PP-R is a combustible material and not suitable for potable water.

When it comes to comparing the performance of CPVC to PP-R, the facts clearly speak for themselves. Whether you’re evaluating overall reliability, ease of use, or health and safety, FlowGuard Gold and Corzan® CPVC outperform PP-R, and the industry has the facts to prove it!