What Is the Difference Between PEX A and PEX B? A Comprehensive Comparison

difference between pex a and pex b

In the ever-evolving landscape of plumbing materials, the battle between PEX-A and PEX-B takes center stage. As homeowners and professionals alike seek to optimize their piping systems, understanding the nuances between these two contenders becomes paramount. So, let’s dive into the intricate world of PEX tubing and unravel the mystery of the difference between PEX A and PEX B.

Imagine this: you’re embarking on a journey to select the most suitable piping for your project. In one corner, we have PEX-A, with its impressive flexibility and remarkable resilience. And in the other corner, PEX-B steps up with its own set of strengths, showcasing its robust structure and steadfast reliability. As we navigate through the intricacies of these two, we’ll uncover the distinct attributes that set them apart and help you make a truly informed choice. So, fasten your seatbelts as we embark on an exploration that promises to decode the enigma of PEX B vs PEX A.

Table of Contents

Understanding PEX-A and PEX-B

PEX pipes come in different variations, each with its own set of characteristics and benefits. PEX-A and PEX-B are two prominent types, each suited for specific applications and scenarios. While both types are made from the same material, they undergo different manufacturing processes that result in distinct properties. What to do about a collapsed drain is an important consideration when choosing between these pipes. Let’s delve into the specifics of these two PEX pipe variations and unravel their unique attributes.

Understanding PEX-A and PEX-B

Difference Between PEX A and PEX B

Let’s summarize the key differences between PEX A and PEX B:

Characteristic PEX-A PEX-B
Manufacturing method Peroxide cross-linking Silane cross-linking
Crystallinity Lower Higher
Density Lower Higher
Strength Lower Higher
Flexibility More flexible Less flexible
Burst pressure Higher Lower
Temperature resistance Better at low temperatures Better at high temperatures
Cost More expensive Less expensive
Joining method Expansion fitting Compression fitting

Overall, PEX-A is more flexible and has a higher burst pressure than PEX-B. However, PEX-B is stronger and has better temperature resistance. The best type of PEX for a particular application will depend on the specific requirements.

Pex B vs Pex A in Details

  • Manufacturing method: PEX-A is made using the peroxide cross-linking method, while PEX-B is made using the silane cross-linking method. The peroxide cross-linking method results in a lower crystallinity and lower density than the silane cross-linking method.
  • Crystallinity: Crystallinity is a measure of the degree of order in a material’s molecular structure. A material with a higher crystallinity is more rigid and less flexible. PEX-A has a lower crystallinity than PEX-B, which makes it more flexible.
  • Density: Density is a measure of the mass per unit volume of a material. A material with a lower density is lighter than a material with a higher density. PEX-A has a lower density than PEX-B, which makes it lighter.
  • Strength: Strength is the ability of a material to resist deformation. PEX-B has a higher strength than PEX-A.
  • Flexibility: Flexibility is the ability of a material to bend without breaking. PEX-A is more flexible than PEX-B.
  • Burst pressure: Burst pressure is the maximum pressure that a material can withstand before it bursts. PEX-A has a higher burst pressure than PEX-B.
  • Temperature resistance: Temperature resistance is the ability of a material to withstand high or low temperatures without breaking down. PEX-B has better temperature resistance than PEX-A.
  • Cost: PEX-A is more expensive than PEX-B.
  • Joining method: PEX-A is typically joined using an expansion fitting, while PEX-B is typically joined using a compression fitting.

Importance of Choosing the Right PEX Type

Selecting the appropriate PEX type for your plumbing project is crucial. The differences between PEX A and PEX B can significantly impact the performance, longevity, and cost-effectiveness of your plumbing system. By understanding these differences, you’ll be better equipped to make an informed decision that aligns with your project requirements and priorities.

The Basics of PEX Pipes

PEX Pipes

Before we delve into the distinctions between PEX-A and PEX-B, let’s establish a foundational understanding of PEX pipes. PEX pipes are crafted from a cross-linked high-density polyethylene material to enhance its strength and durability. This cross-linking process involves bonding polymer chains, resulting in a more robust material. PEX pipes are known for their resistance to corrosion, flexibility, and ease of installation.

Advantages of Using PEX Pipes

The adoption of PEX pipes in plumbing systems has been driven by several key advantages. These advantages include resistance to freezing and bursting, reduced heat loss, and expanding and contracting without the risk of leaking. Additionally, PEX pipes are known for resisting chemical and mineral buildup, contributing to improved water quality and flow. They offer a number of advantages over traditional metal pipes, including:

  • Flexibility: PEX pipes are much more flexible than metal pipes, making them easier to install around corners and in tight spaces. This can save time and money on installation costs.
  • Durability: PEX pipes are also very durable and can withstand a wide range of temperatures, from -40 to 200 degrees Fahrenheit. This makes them well-suited for use in both cold and hot water applications.
  • Corrosion resistance: PEX pipes resist corrosion, which can be a major problem with metal pipes. This means PEX pipes are less likely to leak or break over time, saving you money on repairs.
  • Freeze resistance: PEX pipes can expand and contract without breaking, which makes them less likely to burst when frozen. This is a major advantage in cold climates.
  • Cost-effectiveness: PEX pipes are typically less expensive than metal pipes, making them a more affordable option for homeowners and businesses.
  • Easy to install: PEX pipes can be installed using various methods, including crimp fittings, push-to-connect, and expansion fittings. This makes them a good choice for DIYers and professional plumbers alike.

Common Applications of PEX Pipes

PEX pipes have many applications in residential, commercial, and industrial settings. From potable water distribution to radiant floor heating systems, PEX pipes offer versatility and reliability. Their flexibility makes them ideal for installations that involve tight spaces and complex layouts. PEX pipes are used in a wide variety of applications, including:

  • Residential plumbing: PEX pipes are commonly used for water supply lines in homes, including the main water line, cold water lines, and hot water lines. They are also used for irrigation systems and sprinkler systems.
  • Commercial plumbing: PEX pipes are also used in commercial buildings, such as hotels, restaurants, and office buildings. They are used for water supply lines, irrigation, and sprinkler systems.
  • Radiant heating systems: PEX pipes are a popular choice for radiant heating systems. Radiant heating systems use hot water to heat floors, walls, or ceilings. PEX pipes are flexible and easy to install, making them a good choice for radiant heating systems.
  • Snow melting systems: PEX pipes are also used in snow melting systems. Snow melting systems use hot water to melt snow and ice. PEX pipes are resistant to freezing and can withstand harsh winter weather conditions.
  • Geothermal heating and cooling systems: PEX pipes are also used in geothermal heating and cooling systems. Geothermal systems use the ground to heat and cool homes. PEX pipes are flexible and durable, making them a good choice for geothermal systems.

PEX-A Advantages


PEX-A pipes are crafted using the Engel method, a manufacturing process that results in a highly flexible and uniform pipe structure. This flexibility makes PEX-A pipes ideal for installations that require bending and maneuvering through tight spaces. The Engel method involves cross-linking the polymer chains using peroxide, creating a pipe that can expand up to three times its diameter without undergoing deformation.

Crosslinking Method

One of the defining differences between PEX-A and PEX-B lies in their crosslinking methods. PEX-A pipes utilize the peroxide method, which results in a more uniform and consistent crosslinking throughout the pipe. This contributes to enhanced durability and resistance to stress and pressure.

Enhanced Durability and Resistance

PEX-A pipes are known for their superior durability and resistance to impact and abrasion. The uniform crosslinking achieved through the peroxide method translates to a pipe that can withstand the challenges posed by demanding plumbing applications.

Increased Flexibility and Reduced Memory Effect

Flexibility is a hallmark of PEX-A pipes, allowing them to be bent and shaped without the risk of kinking. Additionally, PEX-A pipes exhibit a reduced memory effect, meaning they are less likely to return to their original shape after being bent. This attribute contributes to the overall ease of installation and reduces the need for additional fittings.

PEX-A Drawbacks

While PEX-A pipes offer impressive benefits, they are often associated with a higher cost compared to other PEX pipe types. The advanced manufacturing process and enhanced characteristics of PEX-A pipes contribute to their higher price point.

Limited Availability of Fittings

Another consideration when opting for PEX-A pipes is the availability of fittings. PEX-A pipes require expansion fittings that match their larger diameter when expanded. These specialized fittings may not be as widely available as those for other PEX types.

Susceptibility to UV Light Damage

PEX-A pipes are susceptible to damage from prolonged exposure to UV light. The pipes may degrade over time if used in outdoor applications without proper protection. This limits their suitability for above-ground installations.

PEX-B Characteristics

PEX-B pipes are manufactured using the silane method, which involves using a silane compound to crosslink the polymer chains. This method results in a stiffer pipe structure compared to PEX-A pipes.


Stiffer Structure and Reduced Flexibility

PEX-B pipes are known for their stiffness, which can be advantageous in certain scenarios. However, this stiffness can make them less suitable for installations that require bending and maneuvering through tight spaces.

Affordability and Cost-Effectiveness

One of the standout advantages of PEX-B pipes is their affordability. The manufacturing process for PEX-B pipes is less complex than that of PEX-A pipes, leading to a lower cost per foot.

Compatibility with Cold Temperatures

PEX-B pipes are well-suited for cold temperature applications. Their stiffer structure and reduced flexibility make them less susceptible to deformation and kinking in low-temperature environments.

PEX-B Limitations

While PEX-B pipes excel in terms of stiffness, this characteristic can also be a drawback. The stiffness of PEX-B pipes can lead to reduced kink resistance, making them more susceptible to bending and deforming during installation.

Fitting and Installation Challenges

PEX-B pipes require crimp fittings for installation, which can be more time-consuming compared to the expansion fittings used with PEX-A pipes. The crimping process requires precision and the use of specialized tools.

Long-Term Durability Concerns

The stiffer structure of PEX-B pipes can lead to concerns about long-term durability, particularly in applications where the pipes may experience significant stress and pressure over time.

Key Factors to Consider When Choosing Between PEX-A and PEX-B

Project Requirements and Specifications

The choice between PEX-A and PEX-B should be driven by the specific requirements of your plumbing project. Consider factors such as the layout, space constraints, and the need for flexibility or stiffness.

Budget Constraints and Cost Analysis

Budget considerations play a significant role in the decision-making process. PEX-B pipes are often chosen for their cost-effectiveness, while PEX-A pipes offer enhanced features at a higher price point.

Environmental and External Factors

Environmental conditions and external factors should also be taken into account. If your installation involves exposure to UV light, for example, you may need to prioritize the UV resistance of PEX-A pipes.

Installation Processes for PEX-A and PEX-B

Installation Processes for PEX-A and PEX-B

PEX-A Installation Steps

Tools and Materials Needed

Before embarking on a PEX-A installation, gather the necessary tools and materials. These may include PEX-A pipes, expansion fittings, an expansion tool, a pipe cutter, and a deburring tool.

Preparing the Pipes and Fittings

Measure and cut the PEX-A pipes to the required length. Ensure that the pipe ends are clean and smooth using a deburring tool.

Expansion Method Installation

Use an expansion tool to enlarge the pipe ends. Insert the expansion fittings into the expanded ends, allowing the pipe to contract and secure the fitting.

Connection Techniques

PEX-A pipes are connected using expansion fittings, which provide a reliable and leak-free connection. The expansion method eliminates the need for additional sealants or soldering.

PEX-B Installation Steps

For PEX-B installations, gather the necessary tools and materials, including PEX-B pipes, crimp fittings, a crimping tool, a pipe cutter, and a go/no-go gauge.

Cutting and Handling PEX-B Pipes

Measure and cut the PEX-B pipes to the desired lengths. Handle the pipes carefully to avoid kinking or damaging the material.

Crimping Method Installation

Slide a crimp ring onto the pipe end, followed by a crimp fitting. Using a crimping tool to compress the crimp ring onto the pipe creates a secure connection.

Joining Pipes with Fittings

PEX-B pipes are joined using crimp fittings, which require precise crimping to ensure a tight and leak-free connection. Use a go/no-go gauge to verify the accuracy of your crimps.

Comparing Long-Term Performance and Durability

PEX-A: Longevity and Resistance

PEX-A pipes are renowned for their longevity and resistance to stress and pressure. The uniform crosslinking achieved through the peroxide method contributes to their ability to withstand time challenges.

PEX-B: Predicting Lifespan and Wear

PEX-B pipes offer satisfactory durability, although their stiffer structure may impact their ability to adapt to certain conditions. When considering the lifespan of PEX-B pipes, factors such as installation quality and environmental conditions should be considered.

Safety and Health Considerations

PEX-A and Drinking Water Quality

Both PEX-A and PEX-B pipes are considered safe for transporting drinking water. However, PEX-A pipes, with their uniform structure and resistance to chemical buildup, are often favored for applications involving potable water.

PEX-B and Potential Chemical Leaching

PEX-B pipes, although safe for drinking water, have the potential for chemical leaching over time. Choosing PEX-B pipes with a PEX-B oxygen barrier is recommended to minimize the risk of chemical migration.

Expert Insights and Recommendations

Industry Expert Opinions

Industry experts often recommend assessing the specific needs of your plumbing project before choosing between PEX-A and PEX-B. Consulting with professionals can provide valuable insights tailored to your situation.

Addressing Common Myths and Misconceptions

Various myths and misconceptions surround PEX pipes, including claims about their safety and durability. Dispelling these myths through expert opinions can help you make an informed decision.

Real-World Case Studies

PEX-A Success Stories

Successful projects have used PEX-A pipes to achieve reliable and efficient plumbing systems. These case studies highlight the advantages of PEX-A pipes in real-world applications.

PEX-B Installations in Practice

Real-world installations involving PEX-B pipes demonstrate their cost-effectiveness and suitability for specific plumbing needs. Learning from these experiences can inform your choice between PEX-A and PEX-B.

Maintenance and Repairs for PEX-A and PEX-B

Preventive Measures for Both Types

Maintaining PEX pipes involves regular inspections for leaks, damage, and wear. Implementing preventive measures can extend the lifespan of both PEX-A and PEX-B pipes.

Addressing Common Issues and Repairs

In the event of issues or leaks, repairs for PEX pipes are generally straightforward. Identifying the cause of the problem and utilizing appropriate repair methods can restore the integrity of your plumbing system.

Environmental Impact and Sustainability

PEX-A’s Impact on the Environment

PEX-A pipes are considered more environmentally friendly due to their longevity and resistance to degradation. Their extended lifespan reduces the need for frequent replacements, minimizing waste.

PEX-B’s Eco-Friendly Attributes

While PEX-B pipes may have a shorter lifespan than PEX-A pipes, their affordability and recyclability contribute to their eco-friendly attributes.

Regulations and Code Compliance

PEX-A and Building Standards

Both PEX-A and PEX-B pipes must adhere to building codes and regulations. Ensuring compliance with these standards is essential to the safety and performance of your plumbing system.

PEX-B’s Adherence to Regulations

PEX-B pipes, when installed correctly and by regulations, can provide reliable and efficient plumbing solutions that meet industry standards.

Frequently Asked Questions

Is PEX-A more expensive than PEX-B?

PEX-A pipes are costly due to their advanced manufacturing process and enhanced characteristics.

Are PEX-A pipes more flexible than PEX-B pipes?

PEX-A pipes are famous for their exceptional flexibility, making them ideal for challenging installations.

Can PEX-B pipes be used for outdoor installations?

PEX-B pipes are not recommended for prolonged exposure to UV light, making them less suitable for outdoor applications.

Which PEX type is better for drinking water?

Both PEX-A and PEX-B pipes are safe for drinking water, but PEX-A’s uniform structure often makes it a preferred choice.

Do PEX-B pipes require specialized fittings?

PEX-B pipes require crimp fittings for installation, which require specific tools and techniques.


Understanding the difference between PEX A and PEX B is pivotal when choosing your plumbing needs. As we’ve delved into the intricate details, it’s clear that both variants have their own merits and applications. PEX-A, with its remarkable flexibility and enhanced freeze resistance, stands as a top contender for projects where extreme conditions might be a concern.

On the other hand, PEX-B shines with its affordability and ease of installation, making it a pragmatic option for residential applications. By understanding the nuances and capabilities of both PEX A vs PEX B pipes, you’ll be well to make an informed decision ensuring your plumbing system’s success and longevity.