stesso

Project

Identify the exact section of galvanized pipe you wish to remove. Measure and clearly mark your cut lines with a permanent marker. The most effective way to cut old galvanized pipe is with a reciprocating saw equipped with a blade designed for cutting metal. Hold the saw firmly with two hands and make a clean, straight cut through the pipe at your marks. Be prepared for the pipe to vibrate and for some water to spill into your bucket. An alternative for tighter spaces is a close-quarters tubing cutter designed for steel pipe. If you have access to a threaded joint and prefer to unscrew it, you must use two large pipe wrenches. Place one wrench on the fitting or pipe you want to remain in place to act as a back-up, preventing it from turning. Place the second wrench on the pipe section you are removing and apply steady, strong force to unscrew it (counter-clockwise). This can be very difficult due to age and corrosion.

You're viewing a step from: How to Replace a Section of Galvanized Pipe with PEX

Beginner

30 minutes

2/4 Inventory

This guide provides comprehensive, step-by-step instructions for replacing an old, corroded, or leaking section of galvanized steel water pipe with modern, flexible PEX (cross-linked polyethylene) tubing. The process involves shutting off the water supply, cutting out the problematic galvanized section, preparing the remaining pipe ends, and connecting the new PEX pipe using appropriate transition fittings.

Based on content fromHandy Man· 29K subscribers

Frequently Asked Questions

How difficult is this project for a DIY beginner, and how long should I expect it to take?

This project is rated for beginners, but it requires careful attention to detail and precision. For replacing a small section, a DIY beginner should realistically budget 2-4 hours, accounting for material gathering, preparation, and thorough leak testing. Factors like pipe accessibility and unexpected issues can extend this timeframe.

What are the most critical safety precautions I need to take when cutting old galvanized pipe and working with water?

Always shut off the main water supply and drain the lines completely before attempting any cuts. Wear appropriate personal protective equipment (PPE), including safety glasses, work gloves, and hearing protection, especially when using a reciprocating saw. Be prepared for residual water and rust flakes to emerge from the old galvanized pipe, and have a bucket and rags ready.

Do I need all the specialized tools listed, or can I use more common alternatives for this PEX replacement?

While specific tools like a PEX pipe cutter and depth gauge are highly recommended for clean, accurate, and reliable PEX connections, some alternatives can be used. A reciprocating saw with a metal-cutting blade is ideal for galvanized pipe, but a pipe cutter can work if space allows. Avoid using a hacksaw for PEX as it can create burrs, hindering a proper seal. Investing in the correct tools minimizes common mistakes.

What are common mistakes DIYers make when connecting PEX to galvanized pipe, and how can I ensure a leak-free joint?

A common mistake is not properly preparing the galvanized pipe end (e.g., failing to clean threads thoroughly, not applying enough pipe dope/Teflon tape) or not fully seating the PEX into push-to-connect fittings. Ensure the existing galvanized pipe end is clean, dry, and free of burrs. For push-to-connect fittings, use a depth gauge to mark the PEX, and push it firmly until it bottoms out inside the fitting, then give it a slight pull to confirm engagement. Test all new connections meticulously before finishing.