The cross-linked polyethylene, commonly referred to as PEX, is a pipe popular for home plumbing. It is made up of colorful rolls of plastic tubing, which makes it quite aesthetic. Since it is made of plastic, the PEX pipe is not rigid; it is pretty flexible.
As with flexible objects, the pipe is bound to expand or contract depending on the weather. For this reason, it is a valid concern whether it is safe to use heat tape on PEX pipes.
The simple answer is yes, you can use heat tape on PEX, provided you follow the instructions provided by the manufacturer. This article provides more information about using heat tape on PEX, so read on.

Table of Contents
Can You Use Heat Tape on PEX Pipe?
Despite its name, heat tape is not some kind of adhesive. Rather it is an electrical cable whose purpose is to prevent an object from freezing over by applying a certain amount of controlled heat.
Thus, you can use heat tape to prevent a PEX pipe from freezing during cold weather. Usually, people are concerned that heat tape would melt a PEX pipe since the latter is made of plastic.
However, you should note that PEX pipes are used on radiant heating systems. Therefore, it is unlikely that they would be destroyed by heat tapes.
Still, it is crucial to stick to the manufacturer’s recommendations when using heat tape on PEX pipes.
Different brands of PEX pipes have different heat limits, beyond which the pipe starts sagging.
To prevent this from happening, you should always maintain the temperature of the heat tape below the pipe’s heat limit.
Some PEX pipes have the heat limit indicated on them, which is convenient. You would have to be on high alert to ensure the tape does not exceed this limit. Alternatively, you can get a self-regulating heat tape.
What is PEX?
PEX was created in 1968 by a scientist called Thomas Engle. Engle’s idea was to come up with a strong and durable plastic. Therefore, he cross-linked different types of basic plastics and produced one more robust plastic through the process of radiation.
PEX is used to create pipes that are commonly used for radiant heating systems. As such, PEX is malleable, making it flexible enough to take any shape without breaking.
Also, it is quite sensitive to UV light from the sun, and too much exposure to sunlight may lead to the plastic disintegrating.
PEX’s flexibility makes it easy to install, which is one of the reasons it is popular for home plumbing. Furthermore, the flexibility makes it ideal for extreme weather as it allows room for expansion.
For instance, when it is cold, the pipe expands accordingly when the water inside starts freezing. This reduces the chance of the pipe freezing. Also, this is where a heat tape comes in, as it also prevents a PEX pipe from freezing over when it is cold.
Is PEX any better than copper? Here is a video with detailed comparisons:
Types of Heating Tapes
Self-Regulating Heat Tapes
These are the most widely used heating tapes. The tapes have a heat sensor, which will monitor the prevalent temperature and self-adjust.
When the temperatures are above the freezing point, there is no heat emission. Not only is this convenient and safer, but it will also help you save a few dollars on your energy bills.
Thermostat- Controlled Heat Tapes
TCHT is a hybrid version of the self-regulating heat tape. It basically works the same but has a thermostat to regulate the temperature.
It’s important to note that the thermostat is separate from the tape and requires its own installation kit. For optimum functionality and accurate readings, you should place the thermostat in the coldest area directly on top of the PEX pipe.
Manual Heat Tapes
These are more traditional tapes that require you to plug or unplug them from a power source manually. It would be best if you remain vigilant when using such tapes to prevent igniting fires or wreaking havoc on your property.
These tapes tend to overheat if you leave them plugged in for long periods while the pipe temperature gets warmer.
How Does a Self-Regulating Heat Tape Work?
A self-regulating heat tape looks like a heavy-duty TV antenna dual-lead cable of the older generations. You should have a house current of 120V to run a self-regulating heat tape.
Essentially, a self-regulating heat tape works by heating only when it needs to, to ensure that the temperature of the PEX pipe stays above freezing point. It has two conductors which are only several millimeters apart and are enclosed in a plastic sheath.
Between the conductors are several positive temperature-coefficient thermistors. The thermistors are made of metal oxides which can regulate the required temperature. In this case, they hold a temperature right above the freezing point and maintain it there.
When a part of the pipe starts falling towards the freezing point, the thermistors in that part of the tape conduct current and self-heat to raise the temperature.
Once they stabilize the temperature again, the thermistors stop conducting, and the heating stops. Thus, they do not get too hot to the point of melting the plastic.
In the warmer parts of the PEX pipe, the thermistors do not conduct any current, so there is no unnecessary wastage of electricity. Thus, one vital pro of a self-regulating heat tape is that it can read its temperature the whole time.
Also, it is simple to use and way more effective than manually controlling the temperature of a heat tape. In addition, it is an economical method of protecting a PEX pipe as it conserves electrical energy.
How To Use Heat Tape on PVC?
First, you ought to look to ensure that the heat tape is labeled safe to use on PVC. Also, check whether the tape has a temperature regulator. If these conditions are met, then you are clear to use the tape on a PVC pipe.
Heat tapes are attached to PVC pipes by wrapping the former onto the latter. Wrap the tape around the pipe in a spiral motion, starting from the electrical outlet.
Starting the wrapping action at the electrical outlet will provide you with adequate length to plug the tape without much trouble.
Ensure that the tape covers all the areas that could be exposed to freezing. As you do this, leave some space between the wraps, as wrapping them too close to each other can result in overheating.
Also, avoid wrapping the tape on itself as this could cause a short and possibly, a fire. The end of the wrap should not touch the ground because it could get exposed to moisture.
In addition, you should check whether the heat tape is for use outdoors or indoors – they are usually indicated. If a tape is for the outdoors, use it outside.
Similarly, if the tape is made to be used indoors, then use it inside a building or in protected areas.
More importantly, avoid extension cords at all costs. Always plug the heat tape directly into a three-prong GFCI outlet.
Tips for Using a Heat Tape on A PEX Pipe
Before you can install a heat tape on a PEX pipe, here are a few things you need to consider:
- The Size of the Pipe – This will primarily determine the correct measurements of the heat tape. Before you head to the store, measure the pipes so that you have enough tape, especially if you will be wrapping them. The length of the tape should be significantly longer to cover the entirety of the PEX pipe.
- The Flexibility of the Tape – The tape should fit snuggly but not rigidly. It should allow for some degree of maneuverability for the PEX pipe to expand and contract with the temperature fluctuations.
- Plugs – You attach these at the ends of the heat tape. You can have multiple plugs depending on the size of the tape. For a first-time installation, we recommend you buy a heat tape kit rather than raw heat tape. It may be slightly expensive but comes with pre-attached plugs for easy installation.
Frequently Asked Questions
At what temperature does a PEX pipe melt?
Check for maximum temperature limits as indicated on the pipe. While the highest temperature will differ from one manufacturer to another, 200 degrees Fahrenheit is the general limit. Exceeding this temperature will cause the pipe to melt.
Are there PEX pipes for hot water supply?
Different colors of PEX pipes serve a specific purpose. They come in red, blue, and white, and these color codes are constant across all manufacturers.
Red PEX pipes are used for hot water supply.Blue is for cold water lines, while white can be used for both hot and cold water.
The color codes are only for convenience purposes but are built exactly the same – so they do not affect the performance of the pipes.
Is PEX a good choice for domestic plumbing needs?
Yes, PEX is excellent for your plumbing needs at home. It is easy to install and flexible enough to withstand different temperatures, including freezing cold. They are more withstanding compared to pipes made with copper or PVC.
How do I fix the tape on the PEX Pipe?
Sometimes wrapping the tape around the pipe won’t hold for long. You can use electric tape or a zip tie to fasten the tape. Adhesive heat tapes are available for more permanent installations.
Final Thoughts
You can use heat tape in PEX pipes, provided you adhere to the temperature limits. PEX pipes have maximum temperatures beyond which they could melt. Heat tapes prevent the pipes from freezing when it is very cold.
Self-regulating heat tapes are the best for this purpose as they are simple to use and are economical as they conserve energy. Ensure you follow the manufacturer’s instructions before you wrap heat tape on your PEX pipe.
FAQs
Can you use heat tape on plastic water lines? ›
If your water supply piping is plastic, ONLY use automatic thermostatically controlled heat tape. Non-automatic heat tapes can damage plastic pipes, especially if the taped pipes are covered with insulation.
What is the best insulation for PEX pipe? ›Insulating your PEX is a very vital step in making your PEX last for a long time. And there is no better way to insulate your PEX than using radiant barrier insulation. Other types of insulation would promise you many things but only radiant barrier insulation will deliver at a very affordable price.
How much heat can PEX tubing take? ›For all PEX pipe and tubing, the maximum operating temperature is 200°F. No PEX should be operated at temperatures above 200°F for any length of time. The use of crosslinked polyethylene (PEX) pipe and tubing in high- temperature applications with operating temperatures above 180°F may affect the tubing's design life.
Can PEX burst from freezing? ›Don't Believe the Myth of Freeze-Proof Pipes
Whether you're working with copper, CPVC or PEX – you are not automatically protected from frozen and burst pipes. All of these materials can and will burst when frozen, under the right conditions.
Frozen PEX Pipes Have a Unique Reaction. Due to its flexibility, PEX can expand under the damaging pressure caused by ice formation. If the weather gets cold enough, PEX pipes can and will freeze like any plumbing. However, PEX may be less likely to rupture as a result of freezing.
Will heat tape hurt PEX? ›A: No. You should not use any type of adhesive material on PEX pipe as over time the adhesive material can interact with the PEX and leech into your water.
What is better than heat tape? ›Heating Blankets Bolster Safety and Efficiency
Heating blankets are much more effective than heat tape at keeping pipes warm.
In general, PEX would freeze when surrounding temperatures reach 20 degrees Fahrenheit—especially if the water line is uninsulated.
Is it worth insulating PEX pipe? ›The general rule of thumb: you do not need to insulate your PEX piping if it is passing through interior walls or insulated external walls. However, if you reside in a region with cold winters, you should insulate any exposed pipe that is outside or inside of unheated places like a basement, crawl space, or attic.
Will rodents eat PEX pipe? ›PEX Pipe Is Vulnerable
Rodents Chewing Through PEX Pipe is a common problem in our area. It doesn't matter how old your home is, if you have an attic, you need to watch for rodent damage to PEX Pipe or PVC.
Can you use a heat gun on PEX tubing? ›
Warm the PEX Tube
Though PEX tubing bends well, it can crimp if it is bent improperly. Start by warming up the PEX tubing, either by letting it sit in a warm room or by using a heat gun at the lowest temperature setting.
One unique property of PEX-a is its ability to be heated, using a heat gun, and repaired if kinked in the handling process which eliminates the need to cut the tubing and install a coupling.
Can I use blue PEX for hot water? ›Color-Coded: Red PEX pipes can be used for hot water supply lines, blue PEX for cold water supply, and white for either hot or cold. These colors are just for your convenience. Plumbing code does not require the pipe color to match the type of water supply.
Do shark bites work on PEX? ›SharkBite brass push-to-connect fittings are compatible with PEX, copper, CPVC and HDPE pipe. They come with a PEX stiffener pre-loaded into the fitting for PEX and HDPE, and the stiffener doesn't need to be removed for copper or CPVC applications.
Is it better to crimp or clamp PEX? ›Pinch Clamp Tools Work Better in Tight Spaces
Especially when your PEX is pressed up against a wall—or there is just otherwise very little wiggle room to work—crimp tools can become a much bigger hassle. The larger jaw of the tool means you need ample room behind your PEX to be able to make a proper connection.
Cold temperatures don't affect the strength of PEX pipe either — except in extreme temperatures. However, freeze-resistant pipes are not freezeproof. So it's important to insulate pipe exposed to freezing temperatures during installation.
How long will PEX tubing last? ›In most cases, PEX is extremely durable and lasts up to 50 years or more. PEX piping is also less likely to crack or break than metal pipe because it does not expand and contract as much when heated and cooled.
What causes PEX to crack? ›Ultraviolet rays cause PEX to break down quickly—tubing left outdoors can harden and crack within a couple of months. PEX cannot currently be recycled, because it does not melt as other recyclable plastics do.
Is it OK for hot and cold PEX lines touch? ›Hot and cold PEX water lines run through the same hole in a stud wall. This is not a typical installation; both pipes should have their own holes to pass through the framing.
Can you leave heat tape plugged in? ›Can you leave heat tape plugged in? Modern heat tape can remain plugged in if it has a built-in thermostat. The thermostat automatically turns on the power (and in turn, heat) when the temperature drops to freezing and turns it back off when the temperature rises.
Can you heat PEX to expand? ›
The Properties of PEX
PEX-a's thermal memory refers to the ability to repair accidental kinks in the piping with a controlled heating source, such as a heat gun. PEX-a's elastic memory means it can expand up to three times its diameter and then shrink back down to its original size.
It is interesting to note the bare PEX pipe actually has more heat loss than the bare copper pipe. The PEX has a heat loss of 31.96 Btuh/ft versus 29.634 Btuh/ft for the copper. Pipes with different wall thicknesses will have different amounts of energy loss.
How long does heat tape last? ›Replacing your heat tapes
Heat tapes can only last for three years because they are always exposed to water and electricity, and so you should replace them at least every three years.
Heating Tape, Heating Cable, Heating Cords: At a Glance
Lower power densities and temperatures, with maximum temperatures ranging from 150°F to 500°F, and including low-intensity cables well suited for freeze prevention.
Will heat tape keep pipes from freezing? No method to keep pipes warm is foolproof, but heat tape does well to prevent freezing and bursting pipes. As the temperature drops, the heat tape will warm to stop the water in the pipes from freezing.
What tape can withstand the most heat? ›Fiberglass tapes, basalt tapes, and aluminum foil tapes are commonly used in high temperature gasketing, sealing, lagging, thermal insulation, and encapsulation applications around furnaces, ovens, and hot pipes.
Can you use zip ties on heat tape? ›While it's best to use tape, Cable Ties or Zip Ties will work as long as they are not pulled so tight that they cut into the cable.
Can I use an extension cord for heat tape? ›Heat cable makers warn people against connecting their products to long extension cords because the reduced voltage can cause the cables to overheat.
What temperature will PEX melt? ›PEX does not melt (analogous to elastomers) and is thermally resistant. The maximum heat temperature of the PEX tube is 200 degrees. The maximum heat of the PEX can be up to 180 degrees.
How do I know if my PEX pipe is frozen? ›If you suspect you have frozen PEX water lines, look for these telltale signs. Little to no water flow. When a section of the pipe is frozen, the ice will block the water flow to the faucet. If it's not completely frozen, you may still get a trickle of water.
Can you use spray foam around PEX pipe? ›
spray foam is fine. it is routinely used to fill wall and ceiling cavities that have pex pipe and to air seal around plumbing that penetrates sill plates.
How do you insulate PEX in a garage? ›- Use foam to insulate PEX pipes. Foam is the most popular insulation material for PEX pipes because they are flexible. ...
- Clean the pipes using a wet rag before wrapping them in foam.
- Seal the PEX tubes completely by using insulation tape on the foam insulation's ends.
You can purchase plastic or wooden pipe coverings at most hardware stores to match your decor. Simply spray some adhesive spray over the pipe and wrap your covering around it. Once you're done, cut off any excess with a box cutter or a utility knife – be careful and watch your fingers!
What is a disadvantage of PEX? ›The biggest disadvantage to PEX is that it is unknown how well or long it will last. While PEX piping is warrantied for up to 25 years, it is unknown what could happen to PEX piping as the years go on. Since it is so new, it is hard to know what water will do to the plastic over 30 years.
How do you protect PEX from mice? ›Mice and rats can squeeze through unbelievably small gaps to enter a home, so the first step is to inspect the home's outside perimeter and seal all holes and gaps around vent pipes with a rodent-proof sealant, such as Tomcat Rodent Block.
How do I know if I have PEX A vs PEX B? ›PEX A uses an expansion-style fitting. These fittings are much larger in diameter the PEX B fittings, and require an expansion tool. Using the expansion tool, you enlarge the pipe and sleeve in order slide in the fitting.
What chemicals leach from PEX? ›The PEX Environmental Impact Report (EIR) found that MTBE and tert-Butyl alcohol can leach out from the PEX plastic in amounts that exceed taste, odor and health guidelines set by the State of California for drinking water.
Can you use PEX for forced hot water heat? ›PEX is a flexible plastic material and is ideal for both cold and hot water supplies.
Can you use plastic PEX fittings on heat PEX? ›Plastic PEX fittings are OK
If you're concerned about using plastic fittings instead of metal for PEX, worry no more. Professional plumbers are buying three times more plastic than brass. Brass fittings cost about five times as much, which likely has something to do with it.
PEX pipe is a flexible plastic tubing product used for supplying water in buildings. It is made from cross-linked polyethylene. PEX pipe can become damaged during installation, from freezing or other unforeseen events. Splice a new piece of PEX pipe into the existing pipe to repair the damaged section.
What kind of PEX do I use for radiant heat? ›
1/2" PEX Tubing with Oxygen Barrier is the most popular size for all radiant floor heating applications due to it's flexibility, light weight and ability to deliver large amounts of heat.
What is the best pipe for hot water line? ›Copper pipes are popular for both hot and cold water pipes because they are heat resistant, resist corrosion, and have natural anti-microbial properties. They are more expensive than plastic pipe options.
Do you need to insulate PEX cold water lines? ›The general rule of thumb: you do not need to insulate your PEX piping if it is passing through interior walls or insulated external walls. However, if you reside in a region with cold winters, you should insulate any exposed pipe that is outside or inside of unheated places like a basement, crawl space, or attic.
Can I put heat tape on PEX pipe? ›A: No. You should not use any type of adhesive material on PEX pipe as over time the adhesive material can interact with the PEX and leech into your water.
How do you keep plastic pipes from freezing? ›Exposed pipes are most susceptible to freezing. Remember, the more insulation you use, the better protected your pipes will be. Use heat tape or heat cables. Heat tape or thermostatically controlled heat cables can be used to wrap pipes.
Can you run hot water through blue PEX? ›Color-Coded: Red PEX pipes can be used for hot water supply lines, blue PEX for cold water supply, and white for either hot or cold. These colors are just for your convenience. Plumbing code does not require the pipe color to match the type of water supply.
Why is my PEX pipe sweating? ›Yes, it is normal for pipes to sweat sometimes. Sweating — or condensation — occurs when the cold water inside the pipes meets the warm and humid air inside the building. Since the cold water attracts moisture from the warm air, it condenses on the pipes.
At what temperature will PEX pipe freeze? ›In general, PEX would freeze when surrounding temperatures reach 20 degrees Fahrenheit—especially if the water line is uninsulated.
How long does it take to unfreeze a PEX pipe? ›How long does it take for pipes to unfreeze? Using any of the handful of methods to thaw frozen pipes will typically take about 30 minutes. This can vary depending on the weather, how long the pipe has been frozen and where the pipe is located. Any of these factors can cause the thawing process to take longer.
What do plumbers use to unfreeze pipes? ›If the pipes have frozen and burst, a plumber can fix them. If the pipes are frozen but have not burst, a plumber can remedy them by applying a heat gun to thaw them. For an interim solution, a homeowner could use a hair dryer to start the thawing process.
Can pipes freeze in one night? ›
Pipes can freeze in as little as six to eight hours, meaning they can freeze overnight. If the outside temperature is below 32 degrees F and your pipes are unprotected, your chances for a frozen pipe increase.
How do you keep water pipes from freezing without electricity? ›Here are tips to keep your pipes warm and safe when the power goes out: Run all of your faucets at a fast drip. This helps prevent pipes from freezing. Try to get a source of heat going: If you decide to use a kerosene space heater, be sure it is vented to the outside and kept clear of any vents.
At what temperature does water freeze in plastic pipes? ›“Any water line that goes below 32 degrees can freeze.” When the water inside a pipe freezes, the ice causes an increase in pressure; when the pressure gets too high, it ruptures.