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Will PEX Freeze In Attic

By March 1, 2022Plumbing
PEX pipes in the attic

Let’s say that your plumbing under the slab of your home has issues. There is no real easy way to fix your plumbing, so you will have to re-route your pipes through the attic. In this case, using PEX pipe is your best choice over more PVC or copper pipes. The fact that PEX will not sweat in high humidity and is highly flexible makes it the top choice amongst master plumbers. Once you determine that you are re-routing your plumbing up through the attic determine the best materials. Will PEX freeze in the attic? It is not likely that PEX pipe will freeze. However, it is possible if it gets cold enough.

Let’s take a look below at the advantages and disadvantages of PEX pipe.

Easy PEX pipe connections
Easy PEX pipe connections

Advantages Of PEX Pipes

Every item in or around our home can offer up an advantage and disadvantage to why it should be used. It is up to the homeowner to determine if the advantages outweigh the disadvantages.

Here are the advantages to using PEX pipe in the attic:

  1. Ease of use – PEX pipe is flexible and running PEX is easy. You can run it in long sections which reduces the number of joints that you might need. Plumbers like this because the PEX pipe can fit in tight places and be flexed up and down and around all areas in the attic.
  2. Installation is easy – PEX connections are easier to install. PEX pipe is connected to valves and a crimping tool is used to secure the pipe to the valve.
  3. More resistant with easy shut-off – PEX pipe is more resistant to bursting in extreme weather changes. It can expand in the winter and shrink back down in the summer. You can also install valves in various locations to lock out the water from that section of pipe.
  4. Hot or Cold water – PEX pipe is free from lead, so it can be used with hot or cold water. This reduces any chances of harmful chemicals getting into your cooking and drinking water.

Disadvantages Of PEX Pipes

Even though you understand the advantages of PEX pipe, you should also note the disadvantages.

  1. Rodents love plastic – keeping your home sealed up tight so that rodents do not seek shelter in your home is vital. If you live in a rural area and experience a rodent invasion in your home, call a professional to remove the rodents before they can chew through your PEX pipes.
  2. Certain PEX tubing isn’t liked – professionals have some issues with using PEX pipe because it is closely related to polybutylene. Since PEX pipe is fairly new in the industry, it is yet to be proven.
  3. Freezing temps outside – as long as the PEX pipes are used inside the home and not on exterior walls they will function properly. Exposing PEX pipes outside in freezing temperatures will cause them to break down and not work. Simply because you cannot insulate them outside and prevent a freeze explosion.
Crimper tool for PEX pipe installation
Crimper tool for PEX pipe installation

How Do I Prevent This

The main reasons for installing PEX pipes in your attic are their flexibility and sustainability. The ability for PEX pipe to expand and contract when in freezing temps and return back to their normal size after thawing has occurred makes PEX pipe highly desirable. Nothing is freeze-proof but PEX pipe is the closest option against freezing.

Here is how you can reduce the chances of the PEX pipes freezing:

  • Keep your home at 55 degrees Fahrenheit.
  • Shut off the water to your outside faucets and drain pipes.
  • Keep the inside faucets on a slow drip so water will continue to flow.
  • Insulate your PEX pipe in cold weather areas so it doesn’t freeze.
  • Install a water monitor to alert you when temperatures might get to a freezing point in the room.
  • Also, consider installing a frost-free sillcock.

Can PEX Pipe Freeze

If temperatures drop below 20 degrees, PEX pipes can freeze. This is often caused by ice formations in and around the pipe. This prevents any flexibility of expansion and can break the pipe.

PEX pipes’ ability to expand and contract is what makes them so resistant to freezing. PEX is not as likely to be become overstressed as compared to copper pipes. Copper pipes and PVC do not have the flexibility and thus a build-up of pressure can cause them to burst in the cold fairly easily in freezing temperatures. Luckily, the PEX materials allow flexibility and can accommodate the pressure build-up.

PEX pipes can still freeze. The thawing process should begin as such:

  • Connect a commercial-grade heating system that pumps heated water through a tube to the frozen water in the pipes and returns the cooler water back for reheating.
  • Soak towels in hot water and wrap them around the pipes to promote instant thawing.
  • Consider using a hand-held fan or a blow dryer from a distance. Not too close where you could melt the plastic.
  • Low-wattage electrical heating tape

How Much Does It Cost

The cost to re-route your plumbing or having a total re-plumb of your home ranges depending on where you live and the cost of materials. Choosing PEX pipe is a great idea as it is a cheaper material and easier to navigate in tight spaces, like an attic or crawl space. The national average for re-plumbing a home is $7,300.

While learning about PEX pipe in your attic, you should also explore does PEX pipe freeze. Having PEX pipe in the attic would likely be exposed to colder and warmer elements. It is a great idea to understand if PEX pipe freezes before using it in any location of your home.

Since we are on the topic of freezing pipe possibilities. It is important to learn about how freezing pipes thaw. In many cases, you will want to expedite the process of thawing your pipes. Take a look at will frozen pipe thaw on their own to learn more.

Finally, as you go about having your plumbing checked and updated, you might want to have your home inspection team check for leaks in the walls of your home. Most homeowners do not have the equipment or knowledge for searching for water leaks inside the walls.

Professional PEX pipe installation
Professional PEX pipe installation

When Do I Call A Professional

Calling on a professional master plumber at this point is a great idea. Anytime you are in a position to make adjustments to your home’s plumbing system, you will want an expert to take charge. Installing PEX pipe in your attic can be a great way to re-route your plumbing from other areas of the house.

However, make sure that you hire someone who understands the proper way to complete this project without causing further damage to your home. Hire a master plumber with a high reputation in your community to complete this project.


Reaching out to a professionally licensed master plumbing contractor is a stellar idea. They can come out to your home and review your entire plumbing system. Then make recommendations for any changes that might enhance your plumbing. If you want PEX pipe installed in your attic, they can look that over as well as inform you if it is a good idea for your situation.

You might also want to reach out to your local home inspection team. The home inspection team can conduct a full inspection of your home, which includes the attic and all of its working parts. The roof, open air space, HVAC unit, vents, and insulation in the attic all must be in top shape before investing in PEX pipe installation in your attic. Call on Alpha building inspections to conduct your home inspection in Merrimack, New Hampshire, and surrounding areas.