Benefits of Installing PEX Plumbing for Water Heating: A Beginner’s Guide

Looking for a cost-effective, durable plumbing solution for your next DIY project? See the benefits of installing PEX plumbing to make your easier decision.

In this article, we’ll highlight the key benefits of using PEX pipes for your plumbing projects, compare it to other types, and explain why it’s a smart option for your next installation or repair.

What You Need to Know Before Installing PEX Plumbing

What Is PEX?

PEX (cross-linked polyethylene) is a flexible plastic tubing used in plumbing and heating. The cross-linking process makes it stronger, more durable, and resistant to temperature extremes and chemicals. Compared to copper or PVC, PEX is easier to install, more flexible, and less likely to corrode, making it a great choice for both residential and commercial systems.

Pros of PEX Plumbing

• Flexibility:
  PEX pipes can bend around corners and obstacles without needing additional fittings, reducing the number of joints required. This makes installation faster and minimizes potential weak points where leaks could occur.
• Cost-Effective:
  PEX is generally less expensive than copper or CPVC, both in terms of material cost and installation. Its ease of use also means less time and labor are needed for installation, saving on overall project costs.
• Corrosion Resistance:
  Unlike metal pipes, PEX doesn’t rust, corrode, or develop scale buildup. This ensures long-term, consistent water flow and eliminates issues commonly seen with copper or galvanized steel pipes.
• Quiet Operation:
  PEX absorbs pressure surges, significantly reducing water hammer noise in the plumbing system. This makes it a quieter option for residential and commercial properties.
• Energy Efficiency:
  PEX has better insulation properties compared to copper. It doesn’t transfer heat as easily, which helps conserve energy by reducing heat loss in hot water lines.
• Easy Installation:
  PEX pipes are lightweight and flexible, making them easy to handle, cut, and connect without the need for soldering, glue, or specialized tools. This simplicity is particularly useful in tight or hard-to-reach spaces.
• Durability:
  PEX pipes resist freezing better than copper or PVC. They are also less prone to cracking or bursting during freeze-thaw cycles. Additionally, PEX is resistant to corrosion and build-up from hard water, ensuring longer-lasting performance.

Cons of PEX Plumbing

• UV Sensitivity:
  PEX pipes degrade quickly when exposed to sunlight. UV radiation weakens the material, causing it to break down and release chemicals into the water. PEX should always be stored and installed away from direct sunlight.
• Limited Outdoor Use:
  PEX is not ideal for exterior applications. In cold climates, it can become brittle and crack if water inside the pipe freezes. In hot environments, prolonged heat exposure can cause the material to oxidize and deteriorate over time.
• Chemical Sensitivity:
  PEX can be damaged by exposure to certain chemicals and vapors, such as petroleum products or solvents. Additionally, in areas with highly chlorinated water, PEX may degrade faster and release chemicals into the water.
• Potential Odor and Taste Issues:
  Water running through PEX pipes can sometimes develop an odor or strange taste. This is more likely if the pipes are exposed to chemical vapors during storage or if the water contains contaminants. Improper storage of PEX pipes can exacerbate this issue.
• Attraction to Rodents and Insects:
  Rodents and certain insects are known to chew through PEX pipes, which can cause leaks and structural damage. This makes PEX more vulnerable in areas where pest infestations are common.
• Limited Recycling Options:
  While durable, PEX is not as environmentally friendly as other pipe materials. Recycling options for PEX are limited, which may be a concern for eco-conscious homeowners.
• Heat Limitations:
  PEX pipes cannot be installed near high-heat sources, such as furnaces, wood stoves, or gas water heater vents. Prolonged exposure to high temperatures can weaken the material and reduce its lifespan.

Is PEX Good for Plumbing?

Installing PEX plumbing has become a highly popular choice for all your water heating applications due to its numerous benefits and advantages over traditional plumbing materials like copper or galvanized steel.

This flexible and durable material resists corrosion and freeze damage, making it an ideal option for both hot and cold water applications.

In addition, PEX is less expensive than other plumbing materials, requires fewer fittings, and can be installed more quickly and easily, resulting in significant savings on labor costs.

PEX plumbing systems also offer a quieter experience than metal pipes and have a lower risk of leaking. It is safe for use in potable water systems and is highly resistant to bacterial growth, ensuring a hygienic option for plumbing systems.

Overall, PEX is an excellent choice for plumbing applications thanks to its durability, ease of installation, and cost-effectiveness.

Is PEX Good for Heating?

PEX is a great option for heating applications, particularly in radiant heating systems, due to its flexibility and ease of installation in various configurations.

In radiant floor heating systems, a network of PEX pipes circulates hot water or other fluids through the floors or walls of a building, providing a more efficient and comfortable heating solution compared to traditional forced-air systems.

Thanks to its resistance to scale buildup and corrosion, it is ideal for use in hot water heating systems.

Furthermore, PEX has a low thermal conductivity, which helps to insulate the heated water better than other materials such as metals, minimizing heat loss and enhancing energy efficiency.

By using PEX in radiant heating systems, homeowners can reduce their energy consumption, lower their heating costs, and enjoy a more comfortable living environment.

Is PEX Resistant to High Temperatures?

PEX pipes are designed to withstand a range of temperatures, but its temperature resistance can vary depending on the specific type of PEX used.

Generally, PEX is rated to withstand temperatures of up to 200 F, which is sufficient for most plumbing and heating applications.

However, there are some types of PEX pipes that are specifically designed for use in high-temperature applications, such as PEX-Al-PEX, which is rated to withstand temperatures of up to 210 F.

Choosing the appropriate type of PEX for the specific application is crucial to guarantee optimal performance and avoid damage resulting from exposure to high temperatures.

Can I Use PEX for Pools?

There are many benefits of installing PEX plumbing where the strength and flexibility truly standout, making it an excellent choice for many plumbing and heating applications.

However, it is important to note that PEX is not recommended for use in swimming pool installations due to its limited resistance to certain chemicals found in pool water, such as chlorine. Over time, these chemicals can damage PEX pipes and potentially cause leaks, leading to costly repairs.

In addition to chemical damage, PEX is also vulnerable to degradation from direct exposure to sunlight (UV lights). As a result, it is generally advised to use specialized pool plumbing materials such as PVC that is designed to withstand exposure to pool chemicals and sunlight, ensuring the longevity and durability of the plumbing system.

By utilizing specialized pool plumbing materials, homeowners can avoid potential problems caused by chemical exposure and sunlight damage, providing a more reliable and long-lasting solution for their swimming pool plumbing needs.

Where Not to Use PEX?

PEX is a versatile plumbing material that can be used in a variety of applications, offering many benefits, but there are some situations where it may not be the best choice.

Here are some scenarios where PEX may not be recommended:

• Outdoor use: PEX should not be used for outdoor applications where it will be exposed to direct sunlight or UV radiation, as this can cause the material to deteriorate and become brittle over time.
• High-temperature applications: While PEX can withstand a range of temperatures, it may not be suitable for use in very high-temperature applications, such as steam heating systems.
• Chlorinated water: If the water supply contains high levels of chlorine or other harsh chemicals, such as pools, PEX may not be the best choice, as these chemicals can cause damage to the PEX over time.
• Recirculating hot water systems: In recirculating hot water systems, where hot water is constantly circulating through the pipes, PEX may not be the best choice, as the constant temperature changes can cause the material to degrade over time.
• Gas lines: PEX should not be used for gas lines, as it is not rated for use with natural gas or propane. The most common gas piping material is black steel.

Is It Hard to Install PEX and What Are the Main Issues During Installation?

PEX plumbing is generally considered to be easier to install than traditional plumbing materials such as copper or galvanized steel. The flexibility of PEX allows for easier installation in tight spaces and around corners, and it requires fewer fittings, which can save time and reduce the risk of leaks.

PEX plumbing can be installed using a variety of methods, including crimp, clamp, or push-to-connect fittings. These methods do not require the use of solder or glue, making them easier and safer to work with, even for DIYers with limited plumbing experience.

Here are some common issues that can arise during PEX installation:

1. Proper fittings: The correct installation of fittings is crucial for ensuring a successful PEX installation. Failure to properly install fittings or using the wrong type of fittings can result in leaks and other issues.
2. Kinking: PEX is flexible, but it can still kink if it is bent too sharply or if it is not properly supported. Kinks can restrict water flow and cause damage to the PEX pipe.
3. Crimping: PEX requires a crimping tool to secure fittings to the pipe. Improper crimping can cause leaks or fittings to detach from the pipe.
4. Expansion and contraction: PEX can expand and contract with changes in temperature, which can cause the pipe to shift or pull away from fittings if it is not properly supported.
5. UV exposure: PEX should not be exposed to direct sunlight or UV light, as this can cause the material to degrade and become brittle over time.

Overall, while there are some common issues that can arise during PEX installation, most of these issues can be avoided by following manufacturer’s instructions and best practices for PEX installation, and by using high-quality materials and fittings.

PEX Tubing Installation – Guide & Tips

Installing PEX tubing is easier and more straightforward than other plumbing types, but it still requires effort. Here’s what you need to do to install PEX correctly:

Planning

Before starting the installation, make sure you have a clear plan. Determine the amount of PEX tubing you’ll need, the fittings required, and any additional items that could make a difference. Measure everything carefully and consider any bends or joints that may be necessary. Planning ahead will make the installation faster, easier, and less problematic.

Cutting the PEX

Once your plan is in place, it’s time to cut the PEX. Each cut should be straight and smooth. We recommend using a special cutter designed for PEX tubes. While it may be a little more expensive, it’s worth the investment. If you use a regular cutter, ensure the cut is as straight as possible. Be sure to follow the measurements precisely to avoid running short on tubing.

Setting Up the Tubes and Making Connections

Setting up the pipes after cutting them can be tricky. Here are several methods to make durable, reliable, and watertight connections. For each method, use the correct fittings, connectors, and tools.

1. Standard Method: Insert the fitting into the pipe, slide the copper crimping ring over the fitting, and use a crimping tool to secure the connection tightly.
2. Expansion Method: Use an expansion tool to increase the tube end diameter, then insert the expansion fitting. Once the tube shrinks back to its original size (thanks to the memory effect), place the plastic ring and press it to secure the connection. This method is easier when the pipe is warm.
3. Stainless Steel Clamp Method: Similar to the standard method, use a stainless steel clamp over the tube and fitting. Then, use a ratchet clamping tool to make the connection tight.
4. Push-Fit Methods: Some systems, like Sharkbite and compression fittings, use push-fit connectors.

Always check for leaks before covering the connections with walls.

If transitioning between PEX and copper tubing, use a brass fitting. Solder one end to the copper, and once it cools to room temperature, connect the other end to the PEX tube.

Running the Piping

After figuring out the path for your pipes, it’s time to run the tubing. PEX behaves differently from PVC and copper. It contracts by about one inch per 100 feet of tubing, especially with temperature changes. Ensure there’s at least 30 inches of support for every 6 feet of tubing. We recommend looping the PEX to allow it to straighten when necessary.

Running PEX pipes is simple—drill holes in the wall studs and feed the tubing through. As mentioned, connect the pipes using one of the various methods.

Protect the Line

PEX pipes are durable, but they’re not invincible. Excessive moisture, sunlight, concrete, or anything that touches the tubing can cause damage over time. Protect the pipes with abrasion clips or pipe insulation.

Running PEX in curves can be tricky. Although PEX is flexible, it can break or kink under pressure. To avoid this, use elbow fittings. Steel elbow fittings, for example, support the curve or bend and help prevent breakage.

Test the Line

After installing and securing the pipes, it’s time to test the system for leaks, bad connections, or faulty fittings. Open the water valve connected to the tubing and let water pass through.

First, make sure the water reaches its destination(s) successfully. Then, inspect the entire line for any issues. If you find a leak, cut the section of the pipe and replace it with a new piece, using a fitting and crimping tool. If no leaks are found, you’ve successfully installed the PEX plumbing!

It’s also a good idea to test the system again two or three hours later to ensure no leaks were missed. If you have to replace any sections, test the line again after the replacement.

PEX vs. Copper

PEX and copper are two of the most popular materials for plumbing systems. Here are the main differences between PEX and copper:

1. Cost: PEX is generally less expensive than copper, both in terms of the material cost and the labor required for installation.
2. Flexibility: PEX is more flexible than copper, which makes it easier to work with and allows for easier installation in tight spaces.
3. Corrosion resistance: While copper is highly resistant to corrosion, it can still corrode over time, especially in areas with hard water or high levels of chlorine. PEX, on the other hand, is highly resistant to corrosion and is not affected by hard water.
4. Durability: While both PEX and copper are sturdy materials that can endure various temperatures and pressures, PEX is more resistant to freeze damage than copper due to its flexibility. PEX can expand and contract with temperature changes, making it less prone to burst or crack in freezing conditions.
5. Noise: PEX is a quieter material than copper, as it doesn’t make the same “water hammer” noise that copper pipes can make.
6. Health concerns: Copper pipes can potentially leach small amounts of copper into the drinking water, which can be a concern for some people. PEX, on the other hand, is a safe and inert material that does not leach any harmful substances into the water.

PEX vs. CPVC

While both PEX and CPVC (Chlorinated Polyvinyl Chloride) are suitable for hot and cold water systems, here are some key differences between the two:

1. Flexibility: PEX is more flexible than CPVC, which makes it easier to work with and allows for easier installation in tight spaces.
2. Cost: PEX is generally less expensive than CPVC, both in terms of the material cost and the labor required for installation.
3. Resistance to freezing: PEX is more resistant to freeze damage than CPVC, which can crack or split if it freezes.
4. Chemical Resistance: CPVC is more resistant to certain chemicals than PEX, making it a better choice for some industrial applications.
5. Temperature and pressure rating: CPVC has a higher temperature and pressure rating than PEX, which makes it a better choice for hot water applications or high-pressure systems.
6. Installation method: PEX is typically installed using a crimping tool or compression fittings, while CPVC is typically installed using solvent cement and threaded fittings.
7. Health concerns: CPVC can potentially leach small amounts of chemicals into the drinking water, which can be a concern for some people. PEX, on the other hand, does not pollute water.
8. Longevity: PEX has a shorter track record of use in plumbing systems than CPVC, but is generally considered to have a longer lifespan due to its resistance to corrosion and chemical degradation.

PEX vs. Galvanized Pipes

While PEX and galvanized pipes share some similarities and benefits, they also have distinct differences in terms of their properties, installation methods, and suitability for different applications.

1. Corrosion resistance: Galvanized pipes are coated with zinc to prevent corrosion, but over time, the coating can wear away, exposing the iron underneath to rust. PEX, on the other hand, is highly resistant to corrosion and will not rust or corrode.
2. Installation: PEX is more flexible and easier to install than galvanized pipes, which are rigid and require threading and welding to connect.
3. Cost: When it comes to material expenses and installation labor, PEX pipes are usually more affordable than galvanized pipes.
4. Health concerns: If galvanized pipes are old or corroded, they have the potential to contaminate drinking water with lead. In contrast, PEX is considered a safe and inert material that does not introduce any hazardous substances into the water supply.
5. Durability: PEX is a durable material that can withstand a range of temperatures and pressures, while galvanized pipes can be prone to leaks and corrosion over time.

Overall, PEX is a popular choice for plumbing systems due to its flexibility, corrosion resistance, and ease of installation, while galvanized pipes are an older technology that may be found in some older homes but are being phased out in favor of newer, more reliable materials like PEX.

PEX vs. PVC

PEX and PVC have both similarities and differences, including benefits, that should be taken into account when choosing a piping material for a specific plumbing application.

1. Flexibility: PEX is more flexible than PVC, which makes it easier to work.
2. Resistance to freezing: PEX is more resistant to freeze damage than PVC, which can crack or split if it freezes.
3. Cost: Compared to PVC materials, PEX is generally more expensive in terms of cost.
4. Durability: PEX is a durable material that can withstand a range of temperatures and pressures, while PVC can become brittle over time and may crack or break.
5. Health concerns: PVC can potentially release small amounts of chemicals into the drinking water, which can be a concern for some people. PEX, on the other hand, is a harmless material that does not leach any harmful substances into the water.
6. Compatibility with other types: PEX is compatible with both copper and PVC systems, which makes it a versatile material for retrofitting or upgrading existing plumbing systems. In contrast, PVC is only compatible with other PVC pipes and fittings, which limits its applications in certain plumbing systems.
7. Temperature and pressure rating: PVC is a better choice for low-pressure systems or applications with lower water temperatures.

While PEX is used mainly in plumbing systems and radiant heating, PVC is commonly used for drainage and waste systems or low-pressure water systems.

PEX vs. ABS

There are some significant differences between PEX and ABS (Acrylonitrile Butadiene Styrene), even though they are both commonly used materials in plumbing systems.

1. Flexibility: Compared to ABS, PEX is more flexible, making it easier to work with and allowing for simpler installation in tight spaces.
2. Resistance to freezing: Compared to ABS, PEX is more resistant to freeze damage, as ABS can crack or split if exposed to freezing temperatures.
3. Cost: ABS pipes are relatively inexpensive and readily available, making them a popular choice for low-cost plumbing systems. In contrast, PEX pipes may be more expensive due to their durability and flexibility, which can make them a better long-term investment.
4. Health concerns: ABS pipes have the potential to release small amounts of chemicals into drinking water, which can be a concern for individuals who prioritize water quality and safety. The leaching of chemicals occurs due to ABS’s composition, and it may be more pronounced when water temperatures are high or when there is prolonged contact time. In contrast, PEX pipes are an inert material that does not contain any harmful substances that could potentially contaminate the water. Thus, PEX is considered a safer option for those who want to ensure the purity and safety of their drinking water.
5. Temperature and pressure rating: ABS has a lower temperature and pressure rating compared to PEX, which means that it is better suited for low-pressure plumbing systems or applications that involve lower water temperatures. However, for high-pressure systems and applications that involve hot water, PEX is the preferred choice due to its superior performance under these conditions.

Overall, PEX is a popular choice for plumbing systems due to its flexibility, durability, and resistance to freezing, while ABS is commonly used for drainage and waste systems. The choice between PEX and ABS will depend on the specific needs of your plumbing system and your personal preferences.

PEX Problems

While PEX offers many advantages, it does come with some drawbacks that can lead to issues affecting the tubing in your home. Below are some common challenges and how to address them:

Dezincification

One of the most frequent problems with PEX installations, particularly with brass fittings, is dezincification. This occurs when cheap brass fittings with high zinc content corrode over time due to water exposure. The corrosion weakens the fittings and their connection to the tubing, which can result in leaks or bursts.

Solution: Use low-zinc brass fittings or opt for fittings made from alternative materials to prevent this issue.

Radiation and Chemical Damage

PEX tubing is highly susceptible to damage from ultraviolet (UV) radiation. Prolonged sunlight exposure can break down the material, causing it to release chemicals into the water—sometimes within just a month.

Chlorinated water can also accelerate decay and cause PEX pipes to release chemicals into the water, whether it’s hot or cold. This makes water from PEX potentially unsafe in some cases.

Solution: Choose the right type of PEX for the environment. Different PEX varieties are designed to resist specific conditions, such as chlorine or slight sunlight exposure. Be sure to select the appropriate type for your needs before installation.

Leaks and Breakage

PEX pipes can be more prone to breakage than copper or PVC pipes. For instance, a hard impact—like striking a wall with a hammer—can crack a PEX pipe.

However, PEX does offer some advantages: it requires fewer connections, reducing the likelihood of leaks. Additionally, it doesn’t develop pinholes like copper and is flexible enough to minimize “water hammer” issues.

Solution: Always locate pipes before doing wall work, and take precautions to avoid direct impacts.

Tips to Avoid PEX Problems

1. Keep PEX Away from Heat Sources
   Ensure PEX tubing is kept at a safe distance from hot surfaces like gas water heater vents or furnace flues. Local codes typically specify the recommended distance.
2. Match Pipe Sizing for Flow
   When replacing or connecting PEX to existing pipes, ensure the tubing and fittings provide the same water flow. Note that the internal diameters of PEX and copper pipes (e.g., ½” PEX vs. ½” copper) differ, so you may need to use a larger PEX size.
3. Protect Pipes from Damage
   Shield PEX tubing passing through studs, slabs, or walls to prevent contact with sharp edges or abrasive surfaces like ducts and joists. If a pipe develops kinks, cut out the damaged section and replace it with a straight pipe and fittings.
4. Use Bend Supports for Tight Curves
   Avoid sharp bends or tight curves with small radii. When necessary, use 90-degree bend support brackets to protect the pipe from stress and potential leaks.

Conclusion

In conclusion, homeowners can enjoy numerous benefits of installing PEX plumbing making it the best choice for homes.

With superior flexibility, PEX can bend and curve around corners and obstacles, reducing the need for extra fittings and joints.

Its resistance to freeze damage ensures that the pipes won’t burst or crack during cold weather.

PEX is also an inert material that doesn’t leach harmful chemicals, ensuring safe drinking water.

Its superior resistance to corrosion, rust, and scale buildup ensures long-lasting performance and reduces maintenance requirements.

PEX has a longer lifespan than traditional materials and is compatible with a wide range of fittings and connectors, making it easy to install and customize plumbing systems.

Overall, PEX provides a reliable, safe, and efficient plumbing system that can meet the demands of modern living.