Do PEX pipes freeze when the temperature dips? Most of us already understand the risks of pipes bursting when they freeze, but you may wonder if you’re immune to this problem when using PEX pipes instead of more traditional options like PVC or copper. In this guide, we’ll explain whether PEX piping can burst in freezing conditions, compare PEX to other popular pipe materials, and cover proactive steps to help you avoid this troublesome plumbing problem.
What Are PEX Pipes?
Before we can dive into the nitty-gritty about PEX pipes freezing, what are they, exactly? PEX stands for cross-linked polyethylene, a type of flexible plastic used in piping for both commercial and residential plumbing systems. These pipes are also commonly used for radiant floor heating and snow melting systems.
When replacing old water pipes, people choose PEX for a few key reasons. The big one is flexibility — unlike PVC or copper, these pipes are more like a stiff garden hose than a typical rigid pipe. This allows easier, cheaper installation and even some resistance against pipe leaks caused by tree roots and freezing.
Do PEX Pipes Freeze Like Copper or PVC?
PEX pipes can definitely freeze in cold temperatures when they’re not properly insulated. Like copper and PVC pipes, PEX piping has minimal insulation on the pipe itself. This means PEX piping is vulnerable to freezing temperatures outside if it’s not buried below the frost line or insulated. PEX pipes can even freeze indoors if your temperature drops too low, which is why proper thermostat settings are essential when preparing to leave town for long periods.
Does PEX Burst When Frozen?
The water inside your PEX pipes can freeze, but the real question is, does PEX burst when frozen?
When water freezes, it expands. For rigid pipes, this is a serious concern and can easily lead to a burst pipe. PEX pipes can stretch and flex somewhat, allowing ice to expand without bursting the pipe. However, this doesn’t mean PEX pipes are immune to bursting when frozen.
PEX piping can still burst if it can’t expand evenly due to a concrete slab or compacted soil surrounding it. There’s also the risk of the pipe getting damaged near fittings. So while PEX piping can tolerate freezing much better than other options, letting it freeze could still lead to you paying for new water lines prematurely.
How To Prevent PEX Pipes from Freezing
Now that we understand the risks of allowing PEX pipes to freeze, what can you do about it? Here are a few tips to help prevent this serious plumbing emergency:
- Keep your home’s thermostat set to a reasonable temperature, including when you’re away. We recommend setting it to at least 55ºF (13ºC).
- Insulate indoor pipes in areas where the heat may not reach, such as your attic, basement, or crawlspace. Use a flexible material, like foam sleeves or electrical heat tape, so you don't restrict the pipes from expanding.
- Before going on vacation, open taps slightly to allow them to drip, ensuring water continues to flow through the pipes instead of freezing.
- Invest in air sealing in your home to prevent cold drafts from dropping your indoor temperature and freezing your pipes.
- Shut off the water supply to outdoor spigots during the winter months. Don’t forget to drain any remaining water from the spigot after the supply is shut off.
What To Do If Your PEX Pipes Freeze
If you’re reading this after your PEX pipes have already frozen (or you’re just looking to be ready for anything), there are a few important steps to take to prevent severe damage to your plumbing and home. Here’s what to do when your pipes freeze:
- Step one: Confirm the pipes are frozen. A completely frozen pipe will stop all water flow, while partially frozen pipes may only put out a slight trickle. Check the pipe for any visible frost on the exterior and search for signs of water damage around fittings.
- Step two: If you’ve confirmed your PEX pipes are frozen, begin thawing by raising the indoor temperature at your thermostat.
- Step three: Pour hot water on some towels and lay them on the frozen sections of the pipe to help thaw the ice.
- Step four: Use a space heater or a hair dryer on the pipes to further help thaw the ice inside.
[Safety note call out] Never use a propane torch or other open flame on PEX pipes. Keep the heat source at least a foot and a half away from the pipe at all times to avoid weakening or melting it.]
- Step five: Apply electrical heat tape to frozen sections.
- Step six: Keep using these methods for a couple of hours to see if you can restore flow.
- Step seven: If you can’t thaw the pipes yourself, it’s time to contact a professional for help. We recommend hiring an expert either way to perform leak detection as well.
When To Replace Frozen or Damaged PEX Pipes
While PEX pipes are much more resilient to freezing than most other materials, they can still become damaged by ice buildup. If, after thawing, there are no water pressure issues and no evidence of water damage in your home, your pipes are probably safe to keep using.
Signs of damage after thawing, such as leaks, water damage, or low water pressure after the ice is gone, are a sign of a problem. Check the indoor lengths for any signs of an issue. If you can’t find any, there’s a good chance the pipe has become damaged underground and will need to be replaced.
You should also have your PEX pipes replaced if they have frozen multiple times, are reaching the end of their 40- to 50-year lifespan, or if you’re already having work done on other underground pipes, such as drain clearing or repair.
Protect Your Home from Freezing Pipes
A frozen or burst pipe is a serious issue that interrupts your water supply and causes thousands of dollars in damage to your home. Whether you’re dealing with a frozen pipe right now and need immediate help, want to upgrade your pipes to PEX to mitigate the risks of freezing temperatures, or wish to prevent this problem from happening in the first place, the plumbers at Ricky Heath can help. To learn more and schedule a service appointment, contact us today!
Frequently Asked Questions
How cold can PEX pipes get before freezing?
Water in PEX pipes starts to freeze at around 20ºF (-6.7ºC). Use heat tape, insulation, and your thermostat to prevent pipes from getting this cold.
Are PEX pipes better than copper for cold climates?
Yes, PEX pipes are better than copper in cold climates. Unlike copper, which is rigid and can’t flex when water expands inside, PEX can expand along with the ice, making it less likely to burst.
Should I replace old copper pipes with PEX in Georgia?
If you’re having any issues with your copper pipes, such as freezing, loud knocking noises, or leaks, they need to be replaced. PEX is a popular option in Georgia thanks to its resistance to bursting and its overall lower cost.
