Upgrading from copper to PEX is becoming increasingly popular among homeowners in the United States. Whether you’re dealing with old, corroded copper pipes or looking for a more flexible, cost-effective plumbing solution, switching to PEX piping can be a smart choice. PEX is easier to install, resistant to freezing, and lasts for decades. In this guide, we’ll walk you through why you should consider upgrading, what tools and fittings you need, and how to successfully replace your copper pipes with PEX.
Why Switch from Copper to PEX?
For decades, copper pipes were the standard in home plumbing. However, with advancements in plumbing materials, PEX (cross-linked polyethylene) has emerged as a more efficient and affordable option. But why should you replace your old copper pipes with PEX?
First, PEX pipes are much easier to install. Unlike rigid copper pipes that require precise cutting, soldering, and welding, PEX pipes are flexible and can be snaked through walls and floors with minimal effort. This makes installation faster and less invasive.
Second, PEX is resistant to corrosion and mineral buildup. Over time, copper pipes can corrode, especially in areas with acidic or hard water. Corrosion can lead to leaks, reduced water pressure, and costly repairs. PEX, on the other hand, does not corrode and maintains water quality for years.
Lastly, PEX is more resistant to freezing temperatures. Copper pipes can burst when water inside them freezes, leading to expensive water damage. PEX pipes, however, expand when frozen and return to their normal shape when thawed, significantly reducing the risk of pipe bursts.
What You Need for Copper to PEX Conversion
Before starting your copper to PEX conversion, gather the essential tools and materials to ensure a smooth installation process. Here’s what you’ll need:
- PEX pipes (PEX-A, PEX-B, or PEX-C, depending on your preference)
- PEX fittings (crimp, push-fit, or expansion fittings)
- PEX cutter (to make clean, precise cuts)
- PEX crimping tool or expansion tool (depending on the fitting type)
- Copper pipe cutter (to remove old copper pipes)
- Deburring tool (to smooth the edges of cut copper pipes)
- PEX adapters (to connect copper pipes to PEX)
- Measuring tape and marker (for accurate pipe measurements)
- Emery cloth or sandpaper (for cleaning copper pipe ends)
Having the right tools and materials will make your installation easier and ensure a leak-free connection.
Choosing the Right PEX Pipes
PEX pipes come in three main types: PEX-A, PEX-B, and PEX-C. Choosing the right one depends on your plumbing needs.
- PEX-A: The most flexible type, ideal for cold climates and tight spaces. It has excellent durability and is easy to work with.
- PEX-B: A slightly stiffer option but more affordable. It is still reliable for most residential plumbing systems.
- PEX-C: The least flexible type and best used in short runs. It is typically used in budget-friendly plumbing projects.
For home plumbing systems, PEX-A or PEX-B is recommended due to their durability and ease of installation.
Do You Need a PEX Adapter?
Yes, a PEX adapter is necessary to connect copper pipes to PEX. These adapters serve as transition fittings, ensuring a secure and leak-proof connection between different pipe materials. The two most common types are:
- SharkBite (push-to-connect) adapters – Quick and easy to install without special tools.
- Crimp adapters – Requires a crimping tool but provides a strong and reliable connection.
If you’re unsure which adapter to use, SharkBite fittings are a great beginner-friendly option.
Safety Tips Before You Begin
Before replacing copper pipes with PEX, follow these safety precautions:
- Turn off the main water supply to avoid flooding or water damage.
- Drain any remaining water from the pipes before cutting them.
- Wear safety gloves and goggles to protect yourself from sharp pipe edges.
- Ensure all connections are tight to prevent leaks.
- Check local plumbing codes to ensure PEX is allowed in your area.
Taking these precautions will help you avoid common mistakes and ensure a smooth installation.
Step-by-Step Guide: How to Connect Copper to PEX
Here’s a step-by-step process to successfully connect copper to PEX:
- Turn Off Water Supply: Shut off the main valve and open nearby faucets to drain any remaining water.
- Cut the Copper Pipe: Use a pipe cutter to remove the section of copper pipe you want to replace.
- Deburr and Clean the Pipe: Smooth the cut edges with an emery cloth to prevent damage to the fittings.
- Choose the Right Fitting: Use a push-to-connect fitting or crimp adapter to connect PEX to copper.
- Measure and Cut the PEX Pipe: Use a PEX cutter to make a clean, straight cut.
- Attach the PEX Pipe: Insert the PEX pipe into the adapter or fitting and secure it using a crimping or expansion tool.
- Check for Leaks: Turn the water supply back on and inspect all connections for leaks.
Following these steps will help ensure a strong and leak-free connection.
Which Fittings Work Best for Copper to PEX?
When transitioning from copper to PEX, choosing the right fittings is crucial. The three main options are:
- Push-to-Connect (SharkBite) Fittings – Easy to install, no tools required. Ideal for DIYers.
- Crimp Fittings – Requires a crimping tool but provides a secure connection.
- Expansion Fittings – Used with PEX-A, offers a strong, long-lasting connection.
Each fitting type has its advantages, but SharkBite fittings are the simplest for first-time users.
Common Mistakes to Avoid
When switching from copper to PEX, avoid these mistakes:
- Not properly cutting and deburring copper pipes – Rough edges can cause leaks.
- Using the wrong type of PEX pipe – PEX-A is best for flexibility, while PEX-B is more budget-friendly.
- Failing to secure fittings properly – Loose fittings can lead to leaks and water damage.
Being mindful of these mistakes can save you time and money on repairs.
Why PEX Crimping Must Be Done Right
Crimping is a critical step in PEX installations. If not done properly, you may experience leaks or weak connections. Always use a PEX crimp tool, ensure the crimp rings are positioned correctly, and test the connection before finishing the job.
How to Check for Leaks After Installation
After installing PEX pipes, follow these steps to check for leaks:
- Turn the water supply back on gradually.
- Inspect all fittings and joints for dripping water.
- Use a dry cloth to wipe around the connections to detect moisture.
- Pressurize the system and check for pressure loss over time.
If any leaks appear, tighten fittings or replace faulty connections.
How Much Does It Cost to Replace Copper with PEX?
On average, replacing copper pipes with PEX costs between $2,000 and $6,000, depending on the home’s size and plumbing complexity. DIY installations are cheaper, while professional plumbing services will add labor costs.
Thoughts: Is Switching to PEX Worth It?
Yes! PEX offers a more durable, flexible, and cost-effective alternative to copper pipes. It is easier to install, resistant to corrosion, and ideal for modern plumbing systems.
The Bottom Line
Switching from copper to PEX is one of the best plumbing upgrades you can make. It’s affordable, easy to install, and long-lasting. Whether you choose crimp, push-to-connect, or expansion fittings, following the correct installation process ensures a leak-free and reliable plumbing system.
By making the switch, you’re investing in a more efficient and modern home plumbing solution that will last for decades.
