Flexible, affordable, and easier to install—no wonder PEX is gaining popularity
Corroded, damaged, or swollen copper pipes could make your home’s drinking water taste or smell funny, and even pose a health hazard. As a homeowner, this is something you’ll want to take care of sooner rather than later.
Today, many DIYers opt for PEX piping over copper when replacing plumbing. There are several advantages, one of which is that it’s easier to install. Learn how to replace copper pipes with PEX pipes in this nine-step guide.
For over fifty years, copper pipes have been one of the most common types of pipes used in homes across America. It’s durable, long-lasting, and tends to stay on tight.
However, corrosion, rot, and even holes in your copper pipes could warrant replacement. This could be a simple spot replacement or require you to cut several feet of pipe and replace it with new material.
Use your senses to determine if your copper pipes need replacing. Do they look rusted, corroded, or damaged? Do they (or does your water) smell? Are there bulges in the ceiling or drywall surrounding your pipes?
If so, it’s time to replace—or you may need to ask a local plumber for help if the job is out of your wheelhouse. Also, be aware of local codes that might make it a code violation to do this work yourself. If you decide to DIY, you may need to purchase special PEX cutting tools.
PEX pipes, or cross-linked polyethylene, are newer, popular alternatives for copper pipes and home plumbing systems. It’s flexible, which makes it easier to install in tight spots, and good for both hot and cold water systems. It’s also more affordable. (If you do it yourself, the cost to replace plumbing in your home starts around $1,500.)
Yet, in some instances, PEX plumbing isn’t a good idea, and there are pros and cons for installing PEX and copper pipes.
For example, if the copper pipes you’re replacing are outside, you shouldn’t use PEX, as UV light can break the material down over time. Plus, you cannot recycle PEX like you can copper, which might be a drawback for eco-conscious homeowners. Research shows that PEX pipes are safe to drink from, but some owners still have concerns since it’s a newer material.
Assuming PEX is the right choice for you and your copper plumbing does need replacing, start by shutting off the main water source to your home. If you know which sink or appliance the pipes run to, turn them on to let the excess water drain out of your pipes.
Measure out the length of pipe you’ll be replacing using your tape measure. With your marker, draw a small mark at the cut points (be sure to cut off all the corroded spots). Use a copper tube cutter to sever off one end.
You’ll want to place a small bucket to help catch water underneath before you start cutting.
To cut your PEX piping, you’ll need PEX tube cutters, not copper cutters. A copper cutter could work if the cutter fits the size of the pipe exactly.
However, using a copper cutter on PEX can result in uneven cutting, requiring you to buy more PEX because you have to make multiple cuts and no longer have enough pipe to cover the damaged section. So if possible, get both types of cutters.
Run your new PEX pipe through the area you are replacing.
To ensure a smooth fit with the new PEX piping, use a deburring tool to remove corrosion and clean the end of the copper pipe. Smooth both the inside and outside of the pipe at least a few inches. You can use a paper towel or a rag to wipe off any excess.
Push-fit connectors, which cost between $5 and $20 at home improvement stores, are how you’ll secure your new pipes.
Read your push-fit connector guidelines for depth (on the package) first. Make a mark on the pipe to see how far back you need to secure the push-fit all the way.
Push one end into the copper pipe up to the depth line. Then connect the other end into the PEX, doing the same thing.
Go to the other side of the room or home, and repeat the same process on the other end of the copper: Cut, deburr, and secure. Once you’ve cut the copper pipe out on both ends, remove it from the area entirely.
If you’re replacing more than five or so feet of copper with PEX, it may be a good idea to drill a few pieces of wood (one every three or so feet) to keep your new flexible tubes from sagging after they fill with water.
Sagging isn’t a big deal—it’s plastic, after all—but if there’s other stuff below your pipes, such as electrical components, or you simply don’t want the pipes sticking out, this can help.
Once done, turn your water on and test. There should be no leaks and no sagging if you took this final step!
Tackling a PEX pipe installation isn’t for everyone. If you don’t mind cutting pipes or working in tight spaces, it’s definitely doable without outsourcing the job.
That said, for more extensive projects, experienced plumbers in your area can help inform you or tackle a PEX installation project. We recommend a pro if you are expanding your plumbing network in the house or doing an extensive overhaul rather than just replacing a small section of pipe.
