• Share:
How to Join Dissimilar Pipes

A master plumber shows the fittings and techniques used to make leak-free connections between copper, PEX, CPVC, galvanized steel and more.

By the DIY experts of The Family Handyman Magazine

Making connections

When you go to add or replace plumbing lines in a house that's more than 10 years old, chances are you won't find new pipes that are the same kind as the old ones. That's no big deal—hardware stores and home centers carry hundreds of different kinds of transitional fittings to help you make the connections. What is a big deal is that those hundreds of different kinds of fittings don't all install the same way.

Some fittings need to be soldered; others take just a wrench or pliers. Several require specific crimping tools, and there are newer styles that simply push together. We asked a master plumber how he deals with the ones he encounters the most, but don't run all over town trying to find the exact fittings we show here. There are usually several suitable solutions using parts available at a local hardware store or home center.

Icemaker line

Water filter line

PEX to copper


Plastic to galvanized steel


Copper to CPVC

Take Them to the Store

Save yourself repeated trips to the home center or hardware store by taking a small chunk of each pipe you plan on using to the store.

Buy approved products

Shielded rubber couplings

Copper to galvanized steel

Push fittings are immediate

Control valves for joinery

Don't guess

Back to Top

Required Tools for this Project

Have the necessary tools for this DIY project lined up before you start—you’ll save time and frustration.

    • 4-in-1 screwdriver
    • Adjustable wrench
    • Wire brush
    • Pipe wrench
    • Plumbers tape
    • Slip joint pliers
    • Tube cutter
    • Wrench set

You'll also need a cinch clamp tool.

Required Materials for this Project

Avoid last-minute shopping trips by having all your materials ready ahead of time. Here's a list.

    • Pipe adapters, couplings and fittings
    • Solder and flux
    • Pipe dope
    • Pipe glue

Comments from DIY Community Members

No comments on the article have been posted yet. Be the first to add your comment!

You will be required to log in or create an account to post a comment.


Add Your Comment

How to Join Dissimilar Pipes

Please add your comment

Log in to My Account

Log in to enjoy membership benefits from The Family Handyman.

  • Forgot your password?
Don’t have an account yet?

Sign up today for FREE and become part of The Family Handyman community of DIYers.

Member benefits:

  • Get a FREE Traditional Bookcase Project Plan
  • Sign up for FREE DIY newsletters
  • Save projects to your project binder
  • Ask and answer questions in our DIY Forums
  • Share comments on DIY Projects and more!
Join Us Today

Report Abuse

Reasons for reporting post

Free OnSite Newsletter

Get timely DIY projects for your home and yard, plus a dream project for your wish list!

Follow Us