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What is PEX Pipe in Plumbing?


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Until recently, it was challenging for the average house owner to do plumbing work themselves. While galvanized pipes are heavy and hard to work with, using a torch to sweat copper joints is not up everyone’s alley. However, with plastic PEX pipes and connectors, even plumbing-phobic homeowners can easily connect them to PEX plumbing and potentially do a small home remodel!

PEX is a short form of “cross-linked polyethylene.” These pipes are typically used for hot and cold water for residential or commercial properties, cooling systems, radiant heating, and insulating electrical cables. You can bend, twist or crush them, but they are guaranteed to return to their original shapes; you only need some low heat! 

It’s difficult to miss the rolls of red and blue PEX pipes while walking down the plumbing section of your local hardware store. You may know more about them now. But did you know these colorful tubes can help repair leaky pipes without calling professionals? Continue reading this article to learn about PEX plumbing, its applications, and its advantages and disadvantages.


What Is PEX in Plumbing? 


One variety of polyethene plastic is PEX. Cross-linking polyethene links create a chemical structure that gives PEX pipe superior strength and flexibility compared to other plastic pipes. These pipings cost less than half as much copper and go in much faster. 

The first PEX material was developed in the 1930s, and since then, it has seen gradual increases in application in plumbing distribution systems for water. You may notice that copper is still required for many industrial and commercial uses. 

However, PEX has many advantages over more conventional piping systems, making it the first choice for most residential projects. Above all, PEX tubes are relatively flexible, which helps make renovating jobs easier. Plus, these tubings have excellent “memory” and a strong desire to return to their previous shape. 

Radiant heating and combination (combo) fire systems are two more places you’ll find PEX pipe in use. Most service plumbers use PEX to fix split, damaged, or leaky copper and CPVC systems. Due to its compatibility with standard copper and CPVC fittings, switching to PEX pipe is quick and easy!

When manufacturing PEX pipings, they begin as long polyethene (PE) plastic fibres. Then these plastic fibres are stretched into hollow tubes or sheets. Specialized equipment sections these tubes into manageable sizes and links them together to make fittings. Compression fittings, also known as crimp rings, secure the connections between the fittings and ensure a watertight seal.

What Are the Available Sizes for PEX Tubing and Pipes?


The most common diameters of PEX tubing and pipes include three-quarter (3/4) inches and half (1/2) inches. When it comes to their length, you can buy these pipes in parts between 4 to 10 feet in length. 

Common Diameters of PEX Pipes: 


A 3/4-inch PEX pipe is ideal for delivering hot water directly from a water heater. You can also use it to provide cold water inside the house. Although, you’re not able use the first 18 inches of PEX pipe as part of the water line from a water heater per most plumbing codes.

On the other hand, ½ inch pipes are the best choice for creating branch supply lines. It is the most typical size that most DIY plumbers run into. The sinks, tubs, and showers in a home get their water from a mainline that branches off into several smaller lines.

Common Length of PEX Pipes: 


Compared to galvanized and copper pipe, PEX pipe and tubing are unique because it is available in exceedingly long lengths. Most hardware stores sell bundles of PEX tubing ranging in length from one hundred to five hundred feet. Such measurements are necessary to accommodate plumbing systems that use a manifold to distribute water to several fixtures.

You can typically buy PEX tubes and pipes in parts between 4 and 10 feet, with the shorter lengths being straight. Sizes like this are more practical for DIYers.


Advantages of Using PEX Piping for Your Plumbing


Clean water and intense pressure are two things every homeowner wants from their plumbing. There are a variety of plumbing fixtures and systems to choose from if you plan on constructing your own home. A little research will tell you that PEX plumbing has more advantages than plastic or copper piping systems! The most significant benefits include the following: 


  1. Flexible and Quicker installations

Being more flexible than rigid pipe is one of the critical advantages of using PEX pipe. Elbows and other fittings are sometimes unnecessary when working with PEX since they can bend around corners. 

Since there are fewer connection points, you can reduce the material cost, and the likelihood of leaks reduces. Further, PEX pipe coils are available in lengths up to a thousand feet, making it possible to install PEX tubes and piping in extensive systems.


  1. PEX Pipes Can Withstand Extreme Cold and Last for Years

Clients generally want long-lasting solutions for both residential and commercial plumbing projects. Because of the longevity of PEX pipes, they are the ideal choice when it comes to durability. Due to its inherent flexibility, PEX is less likely to break than more rigid systems.

Anything as simple as a dent or misaligned fitting weight can endanger an entire network of copper pipes. On top of their fantastic durability, PEX pipes also have incredible flexibility in colder weather. When the water inside PEX freezes, it expands. But it returns to its original shape when the ice melts. 

When water freezes within a pipe, it can expand and potentially burst or fracture. Even a minor fracture can cause water to leak out and perhaps damage your home. For those who live in colder climates, the fact that PEX can withstand temperatures below 32 degrees Fahrenheit is a huge selling point.


  1. PEX is a lot Cheaper Than Metal Plumbing!

As a plumber, you understand that some of your customers are cost-conscious. DIY plumbers may even be doing this to avoid the high cost of hiring an expert in the first place! No matter who it is, PEX’s low price point continues to be one of the primary reasons for its popularity among professionals!

PEX plumbing solutions are often cheaper than other metal plumbing options due to its adaptability. As we’ve already seen, PEX doesn’t need elbow joints or other special equipment to easily work around corners.

Metal piping requires more time and resources to install than its plastic counterpart, as each point requires additional fittings and connections along the way. If you want to save costs without compromising plumbing quality, PEX plumbing is your answer!


Disadvantages of Using PEX Piping for Your Plumbing


So far, I have only discussed the benefits of using PEX piping. But just like anything else, even these incredibly durable and flexible piping and tubes have drawbacks. They include the following: 


  1. Chemicals and Insects Can Harm PEX.

Due to its vulnerability to insect damage, several exterminators advise against using PEX. PEX is plastic; thus, it can gain more damage than metal pipes like copper. 

Rodents like mice can cause significant damage by gnawing through pipes. Remember, though, that this is primarily a rodent issue, not a PEX issue.


  1. Common Installation Issues

Many may find installing PEX to be a breeze. But for others, the process could prove to be an absolute nightmare!

When pipe installation involves many moving parts or you need to bring in lines from other rooms, it’s best to call in the professionals for pipe installation. Furthermore, if you don’t know what you are doing with a fresh installation, it would be wise to leave it to professionals!


  1. You Cannot Use PEX Pipes in Cold or Warm Areas 

PEX plumbing inside a home’s walls is safe in any climate, as it’s insulated to prevent water from freezing. Unfortunately, while PEX has many benefits, you cannot use it outdoors during cold temperatures as PEX is vulnerable to freezing temperatures.

Furthermore, you cannot install PEX pipes near sources of high heat such as recessed lights or water heaters; an intermediary material must be used.




There’s a good chance you’ve heard the term “PEX plumbing” from your plumber or home contractors to describe the piping system in your home. If you don’t know much about plumbings, you might be curious! 

I bring you everything about PEX plumbing, from its standard sizes to its pros and cons. I hope the article was helpful. Thanks for reading till now!