How to Replace Copper Pipes Using PEX

Key remodeling projects usually entail opening up the ceilings, floors, and walls. Such projects offer a great opportunity to inspect and replace any old or faulty plumbing fixtures.

Water pipes require regular inspection since they carry huge volumes of water under extreme pressure. A major burst can be extremely devastating. You should replace old pipes, and this is something you’ll have to do at one point in time.

old copper pipes replaced with pex plumbing pipes

 

Some years ago, water pipes would be replaced by installing brand new pipes made of copper. These pipes were joined with soldered fittings. Soldering them required using a flame-based soldering torch. Assembling the fittings also demanded a lot of skill.

From the 1950s to 2000, copper pipes were the main type of pipes used in the plumbing industry. There were widely used in new constructions and replacing older galvanized iron pipes. Galvanized iron pipes were the standard pipes before the introduction of copper pipes.

However, the use of copper in making pipes has been fading in the last two decades, mainly as a result of the manufacture of more reliable pipes, known as PEX pipes.

PEX is a type of polyethylene comprising of molecules that are cross-linked to create flexible, strong, and durable plastic tubing.

Although copper fittings and pipes are still manufactured today, most professional plumbing companies prefer using PEX pipes for new constructions, extensions, and repairs.

PEX is also ideal for DIY enthusiasts since it’s easier to work with than soldering copper pipes and fittings. PEX tubing can be connected using crimp-ring type of connectors with the help of a crimper.

They can also be connected using push-fit type of connectors. Both connection methods are ideal for joining new PEX tubes to existing copper pipes. However, push-fit type of connectors are more ideal for use by DIY enthusiasts since they don’t require any specialized tools.

Here are the DIY options you can try when you notice a leaking or corroded copper pipe during your home remodeling project:

Spot Fix

In case of leaking copper water pipes, you may choose the easiest approach to repair them by cutting out any damaged section and use PEX to replace it. Such a minimum approach will only require you to use a push-fit type of connector to do the repair.

 

Re-Piping

The best solution to plumbing problems that come with old copper pipes is re-piping them with PEX. Although the initial cost of re-piping might be high, it will save you from frequent repairs and damages.

Re-piping involves bypassing and disconnecting all the existing copper pipes and installing new lines with PEX. You can choose to follow the existing pattern or come up with a new manifold/branch system.

 

Replacing The Visible Runs

A good compromise between spot fixes and full re-piping is replacing visible runs. This is where you replace large pipe sections, at least 10 feet sections of copper piping with PEX. When replacing, you’ll branch out the supply line as needed.

Most DIY enthusiasts prefer to replace the visible runs since it’s not as costly and ambitious like re-piping. Although this approach seems a bit complicated, it’s actually simpler than going spot fix. You can easily replace visible runs with these common supplies:

  • PEX tube cutter
  • De-burring apparatus (for copper pipes)
  • Mini copper pipe cutter
  • 10-foot parts of ½ inch PEX tube
  • Several ½ inch tees (push-fit type)
  • Two ½ inch straight couplings (push-fit type)

 

How to Identify Old or Damaged Copper Pipes

If copper pipes are properly installed, they can serve you for at least 50 years. However, they’ll eventually get damaged. While you might be having copper pipes that are nearing their lifespan, it’s a bit challenging to notice when they need replacement.

When they’re just beginning to corrode, noticing signs of leakage won’t be obvious yet. However, there some signs to look out for such as:

 

Smelling It

With time, you may notice a musty, stale smell that you’re unable to identify properly. You might even get more confused since you might think that the odor is coming from your kid’s room, the bathroom, or the laundry room.

Note whether the smell persists and smells like pond water.

 

Seeing The Evidence

Check whether there’re wide bulges developing on the walls or ceiling. Any bulges are a sign of dripping copper pipes, making the drywall to expand.

 

Seeing It

When opening the ceiling or wall for a certain reason, like adding an extra layer of insulation, you might notice that the copper pipes within the floor or wall cavity are corroded, crusty, and green.

Such pipes might already have some pin-hole leakages that are oozing water slowly but not easily evident.

Any of the above signs tell that the copper water pipe is nearing its lifespan and needs replacement.

 

Replacing Old Copper Pipes with PEX

Step 1: Turning off the home’s main water supply

Since water pipes are usually under extreme pressure when water is running through them, you should start with turning off the home’s main water supply before working on them.

Failure to do this will lead to water spillage and wastage. Moreover, you wouldn’t be able to make repairs with the water turned on. After turning off the home’s main valve, drain all the affected pipes since they would still have water in them.

You can drain them by opening the faucets from all the lower floors. Doing so will prevent any mess when cutting through the pipes.

fast plumbers working on a copper pipe

 

Step 2: Cutting the old or damaged copper pipe

Next, you’ll need to cut the damaged copper pipe on both ends. To do this, start with marking the section of the pipe that needs replacement.

Remember to cut the pipe some inches beyond the corroded section on both ends. Use a metallic pipe cutter to cut the pipe at the section you marked for replacement. Use a mini tube cutter to cut pipes in tight areas.

Any vertical pipe sections should be supported. Supporting them will ensure they don’t slide into the wall cavities.

You can use a wire to support the dangling part of the pipe and secure the wire with a stud. You can secure a copper water pipe to the framing members using a pipe strap.

 

Step 3: Cutting supply branches

In case the copper pipe you’re removing has some branch lines that run to some plumbing fixtures like bathtubs, showers, sinks, or toilets, then you should cut the PEX replacement pipe with a tubing cutter to allow for branch connections.

In case the branches are made of compression fittings or couplings instead of soldered fittings, then disconnect them using a pipe wrench.

Take this chance to replace branched copper lines with new PEX pipes. If you don’t choose to replace them, reconnect them to the brand new PEX tubing section.

 

Step 4: De-burring the cut pipe ends

You should smoothen and clean the cut pipe ends to ensure the pipe connectors fit perfectly. Use the de-burring apparatus for copper pipes to smoothen the outside and inside of the cut pipe ends.

Smoothen the pipe some inches further to ensure any corrosion is completely removed.

 

Step 5: Inserting a new PEX tubing

Take the PEX tubing and measure a length that can replace the cut pipe section. Cut the tubing and allow for some extra inches while cutting to give room for contraction and expansion.

Next, take a straight push-fit pipe connector and force one of its ends onto one end of the existing copper pipe. Ensure the pipe sits fully into the connector.

Next, take the PEX tubing and insert one of its ends into the connector. Ensure it seats fully into the connector. Then repeat this step with the other pipe end using another connector.

If need be, you may install a new push-fit type of ball valve rather than a push-fit pipe connector for enhanced convenience since it allows for shutting off water supply through the line it’s installed.

The valve will usually remain open and only turned off when you want to repair the same line in the future. However, building codes recommend that water shutoff valves must be installed in easily accessible areas. Avoid installing valves in wall cavities that have to be closed upon repair.

 

Step 6: Connecting The Water Supply Pipes For Plumbing Fixtures to PEX

In case the removed pipe section feeds some fixture supply pipes, you’ll need to reconnect them to the brand new PEX section. To do this, start with cutting through the PEX tubing with a tubing cutter.

Next, take the push-fit type of tee-fitting and use it to patch through the PEX tubing. Connect two tee outlets to the new PEX tubing.

Connect the third tee outlet to the water supply line that feeds the fixture. You can as well replace the existing copper supply pipes with PEX.

 

Caution! Be Careful with Electrical Grounding

Homes that have older electrical fixtures usually have them grounded through metallic pipes. Upon replacing the existing metallic pipes with new PEX tubing, the grounding path will be interrupted. PEX is plastic and plastic doesn’t conduct electricity.

It’ll help to confirm whether your electric systems remain grounded after replacing metallic pipes with PEX. In case the grounding connection is lost, call a local electrician to redo the grounding.

This is usually done by using a bonding cable to connect the main panel onto a proper grounding rod. The grounding rod is then driven through the ground and into the soil below.

This issue is rare when it comes to circuit breakers that were properly grounded during installation. However, some older systems use fuses instead of circuit breakers.

Moreover, some local building codes may require plumbing fixtures to be connected to the main grounding system in the home.

In such cases, replacing copper pipes with PEX might interrupt the grounding. Thus, consult your local code of construction for guidelines on grounding electrical systems when plumbing with PEX.

 

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By |2019-10-20T20:42:26+10:30October 20th, 2019|DIY Plumbing|0 Comments

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