If you are installing pipes, you will inevitably run into the issue of deciding what type of piping to use. PEX and PVC pipes can both be useful, but to determine the answer to the common battle of PEX vs PVC: what is the difference and which is better, you need to consider several factors.
PEX is a great choice for easy installation, freeze resistance, and connecting to metal pipes, but it is more expensive than PVC and not good for direct sunlight. PVC has a longer lifespan with great durability and affordability but is not suitable for hot water.
In this article, you will learn the pros and cons of PEX and PVC pipes and the differences between the two, as seen in the chart below. You will also learn which option is better for outdoor, underground, and freezing temperature uses and comparisons to other types of pipes like copper and ABS piping.
PEX vs PVC: Comparison Chart
PEX | PVC | |
---|---|---|
Durability | Flexible and durable for interior use, does not corrode when not in sunlight | Rigid and sturdy, even in direct sunlight, does not corrode and resistant to damage from roots |
Life Expectancy | 25 to 50 years | 50 to 70 years or more |
Flow Rate | May restrict flow some | Does not restrict flow |
Installation | Very easy to install, limited connections | Easy to install, but more connections, especially elbows |
Freezing | Resistant to Bursting, Good up to -40°F. | More likely to burst when frozen, Usually Good up to 20°F. |
Uses | Hot or Cold Water, considered okay for drinking water, but may leach | Only cold water (hot with CPVC), good for drinking water |
Price | $.50 to $2 per linear foot | $.25 to $1 per linear foot |
What is PEX Piping?
PEX is cross-linked polyethylene and it is used to supply water and transport sewage. This type of plastic piping is made by melting high-density polyethylene and forming it into a tube. While it is a relatively recent type of plastic piping introduced around 40 years ago, it has quickly become a popular choice.
PEX is especially common for home remodels because of its flexibility and ease of use. PEX pipes are acceptable for hot and cold water and are safe for drinking water or potable water after it passes inspection. There are some significant upsides to PEX pipe, but there are also some downsides.
Pros
- Freeze Resistance – PEX pipes resist freezing because the material is flexible and will expand with the ice inside. This prevents bursting with cold and extremely cold temperatures up to -40°F. While they can technically still burst, they are unlikely to in normal circumstances.
- Connectivity to Metal Pipes – When you need a connection to metal pipes, most commonly copper, then PEX works well. This is because crosslinked polyethylene will not corrode and they will easily secure together with similar, or even identical, fittings.
- Easy to Install – The flexibility of PEX pipes makes them easy to install. The piping will work well with changes in direction during installation, which means fewer connections, which makes it much simpler to install in certain locations and reduces the risk of plumbing leaks at connection points.
- Quiet – Compared with metal pipes, PEX pipes can reduce the risk of water hammer caused by high pressure in the water system
- Supplies Hot Water – PEX pipes can be used to transport and supply both hot and cold water. As long as the water is at or below 180°F, PEX piping is safe to use. Also, PEX pipes can be certified for drinking water safety.
Cons
- Price – PEX comes with a higher price tag than PVC (although it still costs less than copper).
- Susceptible to Sunlight – Exterior use with exposure to sunlight is not good for PEX pipes because they cannot tolerate UV rays. Because of this, it is generally only recommended for interior and underground usage.
- Contamination Risk – There are three types of PEX and only type B seems to have no leaching problems. PEX pipe can leach BPA and other toxic chemicals and while the number of chemicals may be minimal, this is still a primary concern
What is PVC Pipe?
PVC is polyvinyl chloride, the most popular plastic piping for construction projects because it has been around a long time and meets most building codes for piping besides hot water. It is known for its availability in various shapes and affordability and is commonly used for household drain, waste, or vent (DWV) piping.
PVC is a type of thermoplastic and CPVC, chlorinated polyvinyl chloride, is a related product created from chlorinated PVC resin that is more expensive and adds the temperature resistance many home projects require.
Pros
- Last longer – PVC can last between 50 and 70 years, which is substantially longer than PEX pipes are generally expected to last.
- Low Cost – PVC is very cheap and available in many different sizes and shapes, making it great to use for unique projects. This also makes it a great pipe to choose for non-home improvement-related projects like crafts or other hobbies.
- Exterior Usage – PVC is good for exterior use, so if you need pipes above ground and outside, then PVC is a superior choice. However, you will have to cover the exterior of the piping with water-based paint.
- Recyclable – If you are concerned about eco-friendly materials, then PVC is the better choice. It is accepted for recycling, so once you reach the end of its life or have portions and pieces to discard, you don’t have to worry about just tossing them into a landfill.
Cons
- Higher Leak Risk – Since PVC is stiff and rigid, you will have to use more connections and elbow components. This increases the likelihood of leaks in the plumbing system. It is also more likely to burst from freezing water because it does not flex and expand as PEX pipe does.
- No Hot Water – PVC pipe is not approved for use above 140°F, which means you cannot use it for applications that require hot water like kitchen sinks or tubs. However, CPVC is available for those uses and is safe to 200°F.
What Is The Difference Between PEX and PVC Pipes?
The differences between PEX and PVC involve changes in durability, approved use, life expectancy, flow rate, ease of installation, and total price. These factors can help you determine which option is best for your unique project.
Durability
When it comes to durability, there are some elements to consider. Some durability concerns will depend on whether you are using the plastic pipes for interior or exterior use. PEX pipes are more prone to damage caused by sunlight, so PVC is significantly more durable for above-ground exterior installation. The only degradation of PVC in direct sunlight is with impact strength. If this is a concern, you can paint the pipe with PVC primer and water-based latex paint to protect it.
However, there is another common consideration that homeowners should consider when comparing the durability of PEX vs PVC, which is freeze resistance. This is where PEX is the superior option because it is so flexible that it can resist bursting when ice forms inside. It expands along with the freezing water so that it is unlikely to burst, even in incredibly cold temperatures up to negative 40 degrees Fahrenheit. PVC is rigid and will burst much easier when it freezes.
Both PEX and PVC pipes are resistant to abrasion and corrosion; PVC is a little more. They are also durable to impact and can withstand many abrasive chemicals and electric currents. PVC is also better for preventing damage caused by tree roots for underground pipes. However, when it comes to temperature resistance, PEX can withstand heat much better than PVC.
Use
PEX pipes have different beneficial uses than PVC pipes, so it is critical you keep this in mind before deciding which type is better for your project. PVC is an exceptional choice for water service lines, DMV applications, and other uses. Still, if you need hot water distribution, then it should not be used because it can only accommodate water temperatures up to 140 degrees Fahrenheit. However, if you choose CPVC over PVC, then you can use it for temperatures up to 200 degrees Fahrenheit.
PEX is good for use with hot and cold water applications. It can withstand temperatures as hot as most residential water heaters achieve (up to around 180 degrees Fahrenheit without any concern). Because of this, for any shower, kitchen sink, hot tub, or any other heated location, PEX is the better choice over regular PVC.
Another aspect of use to keep in mind is whether it can be used for drinking water. For any piping, you want to make sure that it holds the proper NSF and ANSI certifications for potable, or drinking, water, but there are other things that you may want to know. For example, CPVC is immune to damage from highly chlorinated domestic water and PVC has been around longer, so it is well-tested for drinkability.
PEX, on the other hand, has some issues even when approved for drinking water. This is because PEX plumbing may leach contaminants into the water supply. Current research still suggests that it is safe to use for drinking water, but one recent study does show that PEX leached over 60 chemical compounds that could be considered toxic.
Finally, both PEX and PVC can be installed underground, but you can learn more about underground use later in this article.
Life Expectancy
Since you probably don’t want to change PVC or PEX pipes all the time, or if you’re buying a property that has older pipes, you may wonder how long PVC lasts or “how long does PEX last?”
In general, PVC will last longer than PEX, and the difference is significant. PVC has a predicted lifespan of 50 to 70 years or more. Conversely, PEX is expected to last 40 to 50 years, creating a lifespan difference of up to 20 years but could be much more.
Some experts recommend replacing PEX pipes in as little as 25 to 40 years with PVC pipes lasting up to 80 or more before needing replacement, which could be a 55-year difference in lifespan under the right or wrong conditions.
Flow Rate
Flow rate can be impacted by the type of piping that you install because of the friction and potentially other factors as well. PVC and CPVC will have a better flow rate when compared with PEX and will cause less than 1% restriction of flow, which is about as good as you can hope for. On the other hand, PEX piping can contribute to a 23% to 54% reduction in flow.
You can expect flow rates of 37 GPM for a 1” PVC pipe, but only expect 26 GPM from a 1” PEX pipe. While there are many other factors to consider regarding water flow, pressure, and velocity, this is certainly something to keep in mind if you need high flow and do not have the space available for wider diameter piping.
Installation
Ease of installation is often a concern, especially if you plan to install the piping yourself. Both PVC and PEX are fairly simple to install, but there are differences. PEX is typically easier to install just because of its flexibility. Neither option typically requires soldering or complicated connections, but PEXis able to bend and form into directional changes, meaning there are fewer connections to make at all. This also means that you have fewer potential leak sources in the plumbing.
PEX’s flexibility also allows you to curve it through misaligned plumbing holes in the walls and reduce the use of elbow connections. You can extend it for longer distances with a single, continuous piece as well, which means less cutting and easier installation. When you need to cut PEX, it is easy to do so.
Remember, none of these reasons mean that PVC is difficult to install, but if you are enticed by a simple installation that doesn’t take much time, then PEX is a clear choice. The one thing that could potentially make PVC easier is the ability to get pieces more readily, especially if you live in a rural or secluded area. PVC is generally available in many sizes and shapes that could suit your project well.
Price
Overall cost of materials and installation is a great way to decide whether to use PEX or PVC, especially when the other factors did not come into play for your purposes. As far as the material itself goes, PVC is quite cheaper on the low end. You can expect to pay around 20 to 40% less for PVC than you would for the same size and amount of PEX.
In general, PEX costs between $.50 and $2 per linear foot compared to $.25 to $1 per linear foot for PVC. These are both considerably cheaper than copper piping. However, you also need to consider installation when calculating cost because PVC installation is a little more difficult and may cost more if you plan to hire someone to do the job.
Finally, CPVC is a little more expensive but still cheaper than PEX, so if you decide between the two, then the overall cost of materials could be a major consideration. Labor will likely still be a little higher for PVC because it takes longer, but doing it yourself comes down to what you want to do and whether you want to deal with the harder installation of CPVC.
Can PEX or PVC Pipes Burst?
While any plastic pipes can technically burst, PEX pipes are less likely to burst than PVC pipes because they are flexible and expand when water freezes inside of them. Because of this, colder regions often utilize PEX than warmer climates. PVC pipes are still less likely to burst when frozen than copper pipes.
PVC vs PEX for Underground and Outside Use
Both PEX and PVC pipes can be installed underground, but there are some considerations. PVC is the more common choice because it is less likely to corrode and the rigid structure withstands high impact and pressure more. It also lasts longer and underground pipe jobs can be pretty difficult, so that may be a consideration.
The downside to underground PVC is its ability to freeze and burst. For colder areas, because of PVC’s susceptibility to breaking under pressure from freezing fluid, you may want to consider PEX. It still works well in most instances as long as it is protected and completely buried.
PEX does not work for outside uses that expose it to sunlight, because UV rays will deteriorate the plastic material. For outdoor use, PVC is the only choice between the two that makes any sense.
PEX A vs PEX B
There are different types of PEX piping to choose from, with PEX A and PEX B being the most common. They are similar and still have the same types of pros and cons, but there are some profound differences to be aware of.
PEX A has been around the longest, as the name suggests. It is very flexible and resistant to kinks, and can be fastened by cold expansion, which means that the end can be fluted before being fitted. PEX A has more cross-linking, which can amplify some of the benefits of PEX piping, like flexibility, ease of installation, and resistance to bursting.
PEX B is more resistant to oxidation and chlorine. It is stiffer, which can be great for preventing impact damage and underground uses. It can withstand growing tree roots more and is also cheaper than PEX A.
PVC vs CPVC
CPVC is Chlorinated PVC, which adds some qualities that are not present in regular PVC pipe, but it also increases the price. One of the main reasons to choose CPVC over PVC is for hot water usage because CPVC has a maximum temperature of 200° Fahrenheit, whereas PVC can only withstand up to 140° Fahrenheit.
In addition, the chlorine in CPVC also prevents biofilm and bacteria formation within the pipes. Also, while both are sturdy and durable, CPVC has higher impact strength and tensile strength, making it the superior choice and usable when PVC alone will not do the trick for a certain project.
Can You Use PEX and PVC Together?
You can use PEX and PVC together as long as you can fit them together properly and do not use them for unintended purposes like using PEX outside or PVC with hot water. There are not any traditional fittings that connect PEX to PVC. While there are fittings and attachments that can work with PEX, copper, and CPVC, very few work with both PEX and PVC.
If you want to connect PEX and PVC, you have a couple of options. The first uses threaded fittings. Choose a threaded male plastic fitting for the PVC pipe that will pair with the metal fitting for the PEX pipe. You should always do it this way to avoid thread stripping or cracked fittings. Once you do this, you also want to double-check the water seal because that can be a common issue with these non-traditional fittings. You can also wrap plumbers tape around it, which can reduce minor leaking.
The other option for connecting PEX and PVC pipe is to use SharkBite fittings. The brand recently introduced a PVC Transition Coupling that can connect PEX and PVC. They work by inserting the ends of each pipe into the coupling and securing the connections. This simple method will cost a little more but can save time and effort.
PVC vs ABS Piping
The main difference between ABS and PVC is that ABS contains bisphenol A, or BPA, which is considered safe but has some concerns as a potential harmful addition. There are also some functional differences between PVC and ABS before deciding on one or the other.
You can easily tell the difference because ABS is always black and PVC is generally white or off-white. ABS connections have to be made with cement designed for this use and PVC is primed and cemented together.
PVC pipe is also more flexible than ABS, but ABS is stronger and can resist higher impact and shock. PVS muffles the sound of water better, but they are similar in cost and both resistant to degradation.
ABS piping is great for some uses because of its durability and temperature resistance, but it is not good for use in direct sunlight, much like PEX pipe. It is used for drain, waste, and vent piping systems and sewer systems for drainage and electrical insulation. However, it cannot be used for drinking water, which PVC pipe is often used to transport.
PEX vs PVC vs Copper
When deciding between pipes, the three most common types you will come across are PEX, PVC, and Copper, so it is important to cover the comparisons we already made for the two plastic varieties with copper.
When it comes to life expectancy, copper is a great ranking, similar to PVC pipe at 50 to 70 years. It is durable and useful for many purposes and often comes with 50-year warranties, far exceeding those you would expect with PVC or, more so, PEX.
However, copper is the most expensive of the three by a substantial margin. You can expect to pay $2 to $4 per linear foot for copper pipe, which is about $1 to $2 more than PVC or PEX. Still, it does offer some advantages.
Since copper will bend significantly before it even has a chance of breaking, it is unlikely to bust under normal, non-frozen circumstances. In areas prone to earthquakes, it is the best choice to avoid damage should a natural disaster strike. Copper pipes also do not corrode and can handle extreme temperatures well. Unlike PEX pipes, they are UV resistant and can also resist bacteria and biofilm accumulation.
One of the downsides to copper pipes is the difficulty of installation. It has to be cut to size due to the rigidity and every time you encounter a corner; you will need elbow fittings, similar to PVC pipes. Copper may also end up in the water, which can make it harder, metallic tasting, and more difficult to digest, according to some people.
Is PEX Better Than PVC?
For some uses, PEX is better than PVC, like when you need to run hot water through it or if you are looking for a simple installation process. However, there are also times when PVC is the superior option, including when the pipe will be exposed to sunlight or looking for a cheap option that will last a long time. This is why it is important to compare and contrast the differences between PVC and PEX for your specific purposes before deciding on one or the other.