PEX, like polybutylene, is a European technology that is less resistant to water conditions and chlorination commonly found in the United States.
Contractors and builders put their reputation on the line with every house they build – so it's important to understand the performance of your piping systems to ensure the reliable delivery of clean, safe drinking water.
A Service History of PEX & CPVC Pipes
FlowGuard Gold® pipes and fittings are America’s most proven non-metallic hot and cold water distribution piping system, having been reliably used to deliver clean, safe drinking water in American homes for 60 years.
The 1960 NAHB Home used a CPVC plumbing system made with the same technology that would evolve into today’s FlowGuard Gold pipes and fittings brand.
Over the past 20 years, PEX systems have been forced to reinvent themselves multiple times due to serious product liability concerns. When you compare the track records, it’s no wonder why FlowGuard Gold pipes and fittings remain the most installed plumbing system brand of the 21st century. Since 2008, there have been at least 10 class-action lawsuits involving PEX plumbing systems stemming from failures due to contact with the drinking water.
How PEX Pipe Can Impact Water Quality
Families rely on their plumbing systems to deliver clean, safe drinking water. No piping material can actually improve water quality, but some are better than others at maintaining it.
Third party studies show that FlowGuard Gold pipes and fittings consistently outperform PEX in both biofilm formation potential and resistance to the effects of chlorine on piping systems.
PEX piping is known to leach regulated substances, including gasoline components such as MTBE, ETBE, TBA and Toluene, into drinking water.
PEX is also a permeable material, meaning that contaminants coming in contact with the outside of the pipe may be transmitted through the pipe wall leading to water contamination. Unfortunately, there are no standard tests or published lists of materials that might cause permeation with PEX, leaving builders, plumbers and homeowners in the dark.
In fact, as evidenced by this image of print-line permeation, PEX manufacturers themselves may not be fully aware of what materials are capable of permeating their materials.
The ink from the print line on this PEX pipe has permeated almost completely through the pipe after less than 10 years.
FlowGuard Gold pipes and fittings do not leach any substances at unsafe levels as determined by both ANSI/NSF Standard 61 and individual state drinking water regulations.
FlowGuard Gold CPVC will not allow outside contaminants to enter your drinking water through the pipe without causing the pipe to fail. Not only do FlowGuard Gold pipes and fittings have superior permeation resistance, but they are also backed by the FBC System Compatible program to assist manufacturers of ancillary products in determining their product's chemical compatibility with FlowGuard Gold CPVC.
Why CPVC Beats PEX in Chlorine Resistance
FlowGuard Gold pipes and fittings are naturally immune to chlorine degradation, due to the inclusion of chlorine in its molecular structure. In fact, CPVC is even recommended by the EPA and AWWA for handling concentrated chlorine disinfectants at water treatment facilities. PEX is only tested to resist chlorine at levels up to 4.3ppm, and the use of chlorine-based disinfectants reduces the temperature rating of PEX by 40°F (from 180°F to 140°F.)
While a FlowGuard Gold plumbing system will never fail under normal use due to chlorine levels, ASTM F2023 is required to determine a time-to-failure for PEX systems under normal use conditions with chlorinated water. This time to failure can be reduced by several factors, including elevated temperatures or pressures, or environmental exposure to UV rays.
According to a 2018 technical note issued by the Plastic Pipe Institute (PPI), it was found that any combination of these factors can significantly reduce the service life of a PEX pipe. The presence of hot chlorinated water is known to cause PEX pipe to degrade causing pinhole leaks and pipe failures. For this reason, the products are tested to ASTM F2023 for chlorine resistance. Unfortunately, a listing to this standard has temperature and pressure limitations which can commonly be exceeded in certain types of construction.
According to the PPI Technical Note: “...exposure to water conditions beyond those used in ASTM Test Method F2023 (i.e., aggressive water quality with an ORP above 825 mV and/or pressures above 80 psig and/or temperatures above 140°F) may cause premature oxidation and eventual brittleness of the PEX material.”
While the PEX tubing may carry a temperature and pressure rating of 100psi at 180°F, the pipe is not listed to perform under those conditions in the presence of chlorinated water. Under these conditions, PEX can fail rapidly – in some cases in less than 10 years after installation.
CPVC piping systems, such as FlowGuard Gold piping systems, are immune to chlorine degradation due to the presence of chlorine in its polymer structure. This natural immunity means a CPVC system can withstand chlorinated water at the temperatures and pressures where PEX will fail.
CPVC Beats PEX in UV Resistance
Ultraviolet rays can come from the sun, fluorescent bulbs or new CFL lightbulbs. UV rays have an aging effect on many surfaces ranging from human skin to plastic pipes. However the impact of UV aging varies dramatically between FlowGuard Gold CPVC and PEX.
UV light consumes the anti-oxidants used in PEX to protect against chlorine degradation. In some cases, just 1 month of exposure to UV rays can reduce the time-to-failure of PEX by up to 21%.
For this reason, leading a PEX manufacturer explicitly states “do not install PEX tubing within 5 feet of direct view from fluorescent lighting without sleeving the tubing with a UV-blocking material.”
Care should be taken to protect all plastic pipes from excessive UV exposure and when handling aged pipes.
While UV exposure may cause discoloration or reduced impact resistance in FlowGuard Gold pipes and fittings, the pressure-bearing capability and life-expectancy under normal use conditions is unaffected by UV.
CPVC Offers Cost-Saving Installation
Recent third party research conducted by Home Innovation Research Labs, a subsidiary of the National Association of Home Builders (NAHB), found that CPVC installs about 15% faster than PEX in its most common configuration.
Plumbers installing FlowGuard Gold pipes and fittings can also save money. The system can be installed quickly and easily using inexpensive cutting tools and a solvent welding process that results in a joint that is actually stronger than the pipe or fitting alone.
PEX requires expensive expansion or crimping tools and PEX fittings, including the body and crimp rings, typically cost several times more than comparable CPVC fittings, and take 2-3 times longer to properly assemble. Not only are PEX fittings more expensive, but even when properly assembled, they can result in joints that have been the subject of several high-profile failures.
For Professional Appearance, Use CPVC
Builders and contractors should be confident and proud of the appearance and performance of every product they use. FlowGuard Gold pipes and fittings provides a straight, professional appearance, eliminating disorganized runs that make the installation look unprofessional and use more materials per home.
||FlowGuard Gold CPVC
|Superior Water Quality
|60 year Service History
|Maximum Chlorine Resistance
|Easy, Cost-Saving Installations