How to Replace the Plumbing on a Walk-In Shower

Is your walk-in shower leaking, dripping, or just not performing like it used to? Replacing the plumbing on a walk-in shower might sound intimidating—but with the right guidance, it’s a manageable project that can save you hundreds (or even thousands) in contractor fees. Whether you’re upgrading fixtures or fixing hidden leaks behind the tile, knowing how to replace the plumbing on a walk-in shower is a valuable skill for any homeowner. Let’s walk through everything you need to know—safely, correctly, and confidently.

Why Would You Need to Replace Plumbing in a Walk-In Shower?

Walk-in showers are sleek, modern, and accessible—but their plumbing systems endure constant moisture, pressure changes, and mineral buildup. Over time, this leads to:

• Corroded supply lines
• Leaky or failing shower valves
• Outdated pipe materials (like galvanized steel)
• Inefficient water flow due to clogged or narrow pipes

According to the National Association of Home Builders (NAHB), over 60% of bathroom remodels include some form of plumbing update—and for good reason. Old or damaged plumbing not only wastes water but can also cause mold, structural damage, and sky-high utility bills.

💡 Pro Tip: If you notice low water pressure, inconsistent temperatures, or water stains on walls/floors near your shower, it’s likely time to inspect—or replace—the underlying plumbing.

What Tools and Materials Do You Need?

Before tearing into your shower wall, gather these essentials:

🔧 Note: Always turn off the main water supply before starting. Test by opening a nearby faucet to ensure no water flows.

Step-by-Step Guide: How to Replace the Plumbing on a Walk-In Shower

Step 1: Remove Shower Fixtures and Wall Access Panel

Start by removing the shower handle, trim plate, and escutcheon. Use a screwdriver to detach visible screws. Behind the trim, you’ll usually find an access panel (often in an adjacent closet or wall). If none exists, you may need to carefully cut a small opening in the drywall or tile—always check for studs and pipes first using a stud finder with AC wire detection.

Step 2: Shut Off Water and Drain Lines

Locate your home’s main water shutoff valve (usually in the basement or garage). Turn it off completely. Then open the shower faucet to drain residual water from the lines. Place towels or a bucket below to catch drips.

Step 3: Disconnect Old Pipes and Valve

Use a wrench to disconnect the hot and cold supply lines from the old shower valve. If you’re working with copper pipes, you may need to cut them with a tubing cutter. For PEX, use a PEX crimp removal tool. Carefully remove the old valve body from the wall cavity.

⚠️ Caution: Avoid damaging surrounding framing or electrical wires. If unsure, consult a licensed plumber—especially if your home was built before 1986 (potential lead pipes).

Step 4: Install the New Shower Valve

Choose a modern pressure-balanced or thermostatic mixing valve (recommended by the International Association of Certified Home Inspectors for scald protection). Follow the manufacturer’s instructions precisely. Most valves require precise alignment with the finished wall surface—use a depth gauge or mock-up board to set it correctly.

Secure the valve to the studs using mounting brackets. Connect new supply lines (½” PEX is easiest for DIYers) using sharkbite fittings or crimp rings.

Step 5: Pressure Test the System

Before closing the wall, perform a pressure test:

1. Cap the shower outlet.
2. Turn the water back on slowly.
3. Check all connections for leaks over 15–30 minutes.

If no leaks appear, you’re good to proceed. If you spot drips, tighten or reseat fittings as needed.

Step 6: Rebuild the Wall and Waterproof

Install cement backer board over the studs. Apply a liquid waterproofing membrane or sheet membrane (like those from Schluter Systems) per code requirements. This step is critical—the International Residential Code (IRC) requires full waterproofing behind tile in wet areas.

For more on building codes and standards, see the plumbing section on Wikipedia.

Step 7: Reinstall Fixtures and Finish Tile

Once the wall is rebuilt and waterproofed, reinstall your shower trim, handle, and spout. If you removed tile, match the existing layout or consider a full refresh for a seamless look.

Common Mistakes to Avoid

Many DIYers run into trouble by skipping key steps. Here’s what not to do:

• ❌ Skipping the pressure test → leads to hidden leaks inside walls
• ❌ Using non-code-compliant valves → risks safety and fails inspection
• ❌ Ignoring waterproofing → invites mold and rot within months
• ❌ Misaligning the valve → causes trim to sit crooked or not seal properly

📊 A 2023 study by HomeAdvisor found that 42% of DIY plumbing failures stemmed from improper valve installation or lack of testing.

PEX vs. Copper: Which Pipe Material Should You Use?

For most homeowners, PEX is the smarter DIY choice—it’s faster, cheaper, and doesn’t require open flames or flux.

FAQ Section

Q1: Can I replace shower plumbing without removing tile?

A: Sometimes—but it’s risky. If you have an access panel behind the shower wall (common in newer builds), you may avoid tile removal. However, most full plumbing replacements require at least partial tile demolition to ensure proper valve alignment, waterproofing, and code compliance.

Q2: How long does it take to replace walk-in shower plumbing?

A: Allow 2–4 days for a typical DIY project:

• Day 1: Demo & removal
• Day 2: Install new plumbing & pressure test
• Day 3: Rebuild wall & waterproof
• Day 4: Tile & fixture reinstallation

Hiring a pro may shorten this to 1–2 days.

Q3: Do I need a permit to replace shower plumbing?

A: Yes, in most U.S. municipalities. Plumbing work that involves altering supply or drainage lines typically requires a permit and inspection. Check with your local building department—fines for unpermitted work can exceed $1,000.

Q4: What’s the average cost to replace shower plumbing?

A: DIY costs range from $200–$600 (valve, pipes, tools). Hiring a licensed plumber costs $800–$2,500, depending on location and complexity (source: Angi, 2025).

Q5: Can I upgrade to a thermostatic valve during replacement?

A: Absolutely—and it’s highly recommended. Thermostatic valves maintain a consistent temperature (±1°F) and prevent scalding, making them ideal for households with children or elderly residents.

Q6: How do I know if my pipes are PEX, copper, or something else?

A:

• Copper: Metallic, reddish-brown, rigid
• PEX: Flexible plastic tubing (red/blue/white), labeled with brand/type
• Galvanized steel: Gray, threaded, prone to rust (common in pre-1970 homes)

When in doubt, take a photo and ask at your local hardware store or consult a plumber.

Conclusion

Replacing the plumbing on a walk-in shower isn’t just about fixing leaks—it’s an investment in safety, efficiency, and home value. With careful planning, the right tools, and attention to waterproofing and code compliance, you can tackle this project successfully—even as a beginner.

✅ You’ve now learned:

• How to safely remove and install a shower valve
• Why waterproofing is non-negotiable
• The best pipe material for DIY success
• Common pitfalls to avoid

Found this guide helpful? Share it with a friend who’s planning a bathroom upgrade! And don’t forget to pin it on Pinterest or tweet it out—your DIY community will thank you.

Got questions? Drop them in the comments below—we’re here to help you build with confidence.