Why is PEX Banned in California? Interesting Facts!

Are you aware that PEX tubes and pipes were once part of a controversy that shook the foundations of the piping industry in the state of California?

If you are not, then this is the right article for you. There is still confusion regarding the tubing legalisation; however, after many legal deliberations, PEX pipes are legal now in California.

Let us look at some of the facts regarding PEX and then the 18 months of PEX’s fate that was volatile and shook the CBSC, the piping industry, and other stakeholders. This article will give you detailed reasons behind the banning of PEX in California.

Why California Banned PEX?

PEX was banned in California till 2010, which initiated a much-discussed debate and controversy. There are certain reasons for which California banned PEX, and a legal battle began. All the reasons are discussed below, which will help you to have a better understanding of why California banned PEX.

[Apart from California, there are some other places as well where pex is not allowed. Check this article to know details]

PEX Legal Battle: The Timeline And Interesting Facts

PEX tubing came from Europe and took the piping industry by storm in the United States. It must have made enemies because of its rise to fame. No other state had any sort of problems with PEX, except California, which has a reputation for banning anything that can endanger health of its residents.

So, when Californian officials thought that PEX might contaminate their domestic freshwaters, they banned it, but it was not that simple.

why pex is banned in california

PEX’s Chemical Reaction

As PEX came into the limelight, the local plumbing bodies, workers, etc., stated that PEX piping reacted with the water generating some kind of chemicals that were harmful to its users. The controversy and legal battle began.

Moreover, it was also believed that this chemical reaction changed the taste and odour of water which is alarming.

The Legal Battle

The CBSC (California Building Standards Commission), within the legal domain of its jurisprudence, approved the EIR (Environmental Impact Report) on the PEX pipes and gave a green signal to adopt the regulations for the inclusion of crosslinked polyethene water transportation mechanism in the CBC (California Plumbing Code).

The CBSC had to revise the EIR as per the direction of the Alameda Superior Court. During this period, a revised EIR report was published that got approval in Aug-Sept, 2010.

However, due to the legal battle, PEX remained in controversy, and as time passed, other interesting disadvantages were exposed to the stakeholders, which are as follows:

Fitting PEX

PEX fitting and joints are up to the standard set by the water board of California; however, the joints are expensive and slight error in its installation can cause severe leakage issues.

The Californian Water Code-WAT clearly states that water should be clear of any impurities that are harmful to the state’s individuals in any way.

The basic law regarding the quality of water is “CHAPTER 10.2. California Safe Drinking Water Bond Law of 1984 [13810 – 13845] (Chapter 10.2 added by Stats. 1984, Ch. 378, Sec. 1.)”

The law makes it quite clear to individuals, manufacturers, and suppliers that any problems that the public faces because of water will be dealt with according to the state law.

Reaction with Chlorine

Water resources are filled with Chlorine to keep them clean from germs. PEX reacts with Chlorine, and with time, the piping gets scaled up, resulting in less water flow. The clogging can also make the pipe crack, and it was also a big issue raised.

The Guarantee Loophole

PEX has a durability of 50 years, but remember that it is the pipe’s guarantee but not of the links or accessories that come with it. The installation of the pipe is cheap, but the associated material is expensive.

For example, a thousand feet coil of 1/2 inch PEX tubing cost a couple hundred bucks whereas a good quality PEX expansion tool costs up to 500 USD. So, this sounds gimmicky and Californian officials were not ready to welcome any such thing.

Chemical Leaching

During the manufacturing of PEX, certain chemicals like t-butanol are left as a residue in the pipes. The residue is a harmful chemical that reacts with water. This chemical is highly detrimental to drinking.

California Plumbing Code states that the pipe is to be tested for these chemicals before the installation. If any pipes are found with traces of MTBE and T-Butanol, before the installation, they should be purified, and if the problem occurs, the piping should not be used.

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The new and revised California Plumbing Code states that the water in the PEX tubes should be flushed regularly to avoid any kind of chemical reaction. The PEX tubing industry has also evolved and has different varieties now. The varieties are categorized by colour schemes like blue PEX is used for cold water only while red ones are for hot water supply lines.

Similarly, the grey or white PEX is used for both hot and cold water. The state is responsible for the health of its people. What took place in the past was to maintain the quality of life of California’s people, which is praise-worthy.

One thing to keep in mind that California has changed its stance towards PEX, and you never know if they are going to put any barrier again. So, if you are California resident, make sure to check the law when you plan to install PEX.

1 thought on “Why is PEX Banned in California? Interesting Facts!”

  1. Looks like someone is in the pocket of the Plumbing Union. Same overload concerns when copper came to market, or PVC and ABS. Dilutes the point.


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