Like any other material, multiple factors could lead to problems with PEX. Some of these factors could be simple over-chlorination of the water running through it or dezincification, which could weaken and break down the fittings used on the piping. Another issue could be the piping failing to pass a pressure test.
They hate PEX because it's MORE reliable than copper, and much faster/easier to install = less money for them. It's also much less expensive which means they don't make as much on materials if they charge that way.
Of course, PEX piping does carry some disadvantages. It will crack and break apart under the influence of strong UV rays (making it unsuitable for most outdoor use). Plumbers require specialized tools to cut and join this type of modern pipe. Additionally, disposing of used PEX pipe sometimes proves problematic.
Currently, PEX plumbing is one of the most widely used plumbing systems around the world. It was temporarily banned in California for a while due to concerns about toxic materials but this was later disproven by laboratory tests.
PEX pipe can be used as a service line based on its corrosion resistance to soil and water, its long life and its oxidative resistance. Our PEX pipe is not suitable for use in areas where the soil is or may become contaminated, including soil used for backfilling.
Common Causes of PEX Pipe Failures
In addition, extreme bends and kinks place a very high local stress on the wall of the pipe, making it more susceptible to oxidative degradation. This is especially true in southern climates where water chlorine levels run high.
PEX Pipe Is Vulnerable
Rodents Chewing Through PEX Pipe is a common problem in our area. It doesn't matter how old your home is, if you have an attic, you need to watch for rodent damage to PEX Pipe or PVC. If you're hearing rustling noises coming from the attic, it's time to do an inspection.
The problem with PEX seems to be that it's contaminated -- it leaves the factory with chemicals used in its manufacture still on the pipe. In time it cleans up, but during that time those chemicals are going into the water.
On average, PEX pipes can last anywhere from 40 to 50 years, and in some cases, even longer. This impressive durability is due to the material's resistance to corrosion, scaling, and chlorine, as well as its ability to withstand high temperatures and pressures.
PEX pipe is safe for drinking water in households and commercial systems. NSF International has teams of toxologists and other technical professionals who administer the NSF 61 standard which requires all components in a water system to be safe for drinking water. This includes PEX pipe systems with drinking water.
Some studies suggest that chemicals used in the manufacturing process can leach into the water supply, posing risks to human health. The possibility of chemical leaching from PEX piping into drinking water has been a significant factor in its ban.
Copper Pipes
The most traditional of plumbing materials, copper is the most widely used option due to its durability and reliability. Copper's lifespan can reach well over 100 years at a time with superior corrosion resistance and is easily manageable with hot and cold water.
Based on this analysis, the PEX pipe material examined appears to have good resistance to chlorinated water. References 1. USEPA.
PEX pipes are very thick but they are still susceptible to rodent damage that can cause pipes to crack or break. Possible Leaching: Although uncommon, some homeowners and plumbing companies have reported a few PEX pipes leaching harmful contaminants like BPA (Bisphenol A) into the water supply.
CPVC is More Effective at Maintaining Water Quality than PEX
Biofilm Growth Potential: Biofilms, including Legionella and other harmful bacteria, can grow inside residential water pipes.
PEX pipes are the top option for plumbing in Florida. But that doesn't mean you should automatically pass up a house that uses other materials.
Lower Lifespan Than Other Materials
While PEX plumbing is cheaper upfront, the cost benefits may be negligible when you consider that it might not last as long as copper or other materials. PEX pipes have an average lifespan of about 40-50 years, while copper can last over 70 years.
PEX PIPING IS NOT Leak Resistant
It's lack of required fittings and flexible nature allow for quicker installs than traditional rigid pipe systems. This seemingly quick and flexible installation does have its downfalls.
Pex tubing is now widely used in water supply projects. Back in history, Pex tubing was created in the 1960s in Europe and was widely used and introduced in the US around 1980.
Back in the late 90's, certain PEX piping systems used yellow brass fittings which, under certain circumstances, dezincified and failed prematurely resulting in a series of class action lawsuits and settlements.
Copper has been a standard plumbing pipe material since the 1960s, and with good reason. First, copper is the preferred choice from a safety standpoint because it preserves drinking water quality. Unlike galvanized steel or cast iron, copper is corrosion-resistant and doesn't leach rust or sediment into the water.
Chlorine
Chlorination badly affects the durability of the PEX plumbing system and shortens its lifespan. The chlorine in the water inside PEX pipes speed-up the brittle oxidative failure of cross-linked polyethylene. This failure leads to sudden leakage and sometimes even bursting of the pipes.
It's a good idea to install 1/2-inch or 3/4-inch PEX for your main lines for adequate water flow. When replacing old water supply lines with PEX the standard is to use the same size plumbing, although you can transition from 3/4-inch to 1/2-inch plumbing with an adapter.
After all, it's not like you want to run a bed and breakfast for mice and rats. However, by providing them an easy to find water source (like a dog bowl) temporarily while trying to exterminate them, this will help you remove their motivation to chew through the pipes to get water.
Bottom line, PEX A is more resistant to burst pressure than PEX B. PEX A's expansive material can handle up to 500 PSI, which makes it reliable in extremely cold temperatures. Since PEX B is a more rigid material, it will not hold up as well in similar situations.