Shower Upgrade: Plumbing Cost To Add A Shower To Your Old Tub

Are you tired of stepping over high tub walls just to take a quick rinse, or perhaps you are worried about safety for an aging family member? Converting your existing bathtub into a walk-in shower is one of the most practical and value-adding upgrades you can make to your home. However, before swinging a sledgehammer, every homeowner needs to understand the plumbing cost to add a shower to your old tub to avoid budget surprises. This guide breaks down exactly what you can expect to pay, the factors that influence pricing, and how to ensure your project meets modern safety and efficiency standards.

What Is the Average Plumbing Cost To Add A Shower To Your Old Tub?

When planning a bathroom remodel, the first question on everyone’s mind is the bottom line. While prices vary significantly based on location, materials, and the complexity of the job, understanding the national averages gives you a solid starting point.

According to recent industry data from 2024, the average cost to convert a tub to a shower ranges between $1,500 and $5,000 for a standard conversion using a pre-fabricated kit. If you opt for a custom-tiled walk-in shower with high-end fixtures, that number can easily climb to $8,000 or more.

The plumbing cost to add a shower to your old tub specifically (labor and pipe work only, excluding tiles and glass doors) typically accounts for about 30% to 40% of the total project budget. Here is a realistic breakdown of where your money goes:

It is crucial to note that these figures assume the existing water supply and drain lines are in good condition. If your home was built before 1980, you might encounter galvanized steel pipes or cast iron drains that require full replacement, which will increase the plumbing cost to add a shower to your old tub.

How Does Moving the Drain Affect the Total Price?

One of the most significant variables in your budget is the location of your drain. In a standard bathtub, the drain is often centered or offset differently than what is required for a shower pan.

If your new shower design aligns perfectly with the existing drain location, you save hundreds of dollars. However, if the drain needs to be moved even a few inches, the complexity spikes. This process involves:

• Cutting into the subfloor.
• Accessing the joists below (sometimes requiring work from the ceiling of the room underneath).
• Re-piping the drainage line to ensure the correct slope (gradient) for proper water flow.

Plumbers generally charge by the hour, with rates in the US ranging from $75 to $150 per hour. Moving a drain can add 3 to 6 hours of labor, plus material costs. Furthermore, if you are converting a tub located on a concrete slab foundation, cutting through the concrete to reroute pipes can double the plumbing labor cost. Always ask your contractor for a specific assessment of the drain alignment before signing a contract.

What Are the Hidden Costs in a Tub-to-Shower Conversion?

While the headline number looks attractive, savvy homeowners know to look for the “hidden” expenses that often appear mid-project. Being prepared for these ensures your renovation doesn’t stall due to lack of funds.

1. Water Damage Remediation

Once the old tub is removed, you may discover rot in the subfloor or mold behind the walls. This is incredibly common in bathrooms older than 20 years. If soft wood is found, it must be replaced immediately to maintain structural integrity. This unexpected repair can add $500 to $2,000 to your bill.

2. Permit Fees

Many US municipalities require a permit for any work involving plumbing changes. Ignoring this can lead to fines and issues when selling your home later. Permit fees typically range from $100 to $500, depending on your city.

3. Waterproofing Upgrades

Modern building codes are stricter than ever regarding waterproofing. Simply installing a shower pan isn’t enough; the walls often require a liquid membrane or cement backer board system to prevent leaks. Skipping this to save money is a false economy that leads to costly repairs down the road. For more detailed information on building standards and safety regulations, you can refer to resources like Wikipedia’s page on Building Code.

4. Accessibility Features

If you are doing this conversion for aging-in-place purposes, you might want to add grab bars, a bench seat, or a zero-threshold entry. While beneficial, these require additional framing and reinforcement inside the walls before the tile goes up, adding to the initial labor cost.

DIY vs. Hiring a Pro: Which Saves More Money?

The temptation to tackle a tub-to-shower conversion as a Do-It-Yourself (DIY) project is strong, especially with countless tutorial videos available online. But does it actually save money?

The DIY Approach:

• Pros: You save on labor costs, which is the biggest expense. You have total control over the timeline and material selection.
• Cons: High risk of errors. Improper sealing leads to leaks that damage floors and ceilings. Mistakes in pipe sizing can result in poor water pressure.
• Verdict: Only recommended if you have intermediate plumbing and tiling experience.

The Professional Approach:

• Pros: Guaranteed workmanship (often with a warranty). Faster completion time (usually 2–4 days vs. 2–4 weeks for DIY). Compliance with local codes.
• Cons: Higher upfront cost.
• Verdict: Highly recommended for most homeowners. The plumbing cost to add a shower to your old tub paid to a professional is essentially an insurance policy against future water damage.

If you decide to hire a pro, always get at least three detailed quotes. Ensure the quote specifies whether they are handling the demolition, disposal, and final cleanup, as these are often billed separately.

Step-by-Step Guide: How the Conversion Process Works

Understanding the workflow helps you manage expectations and communicate better with your contractor. Here is the typical lifecycle of a tub-to-shower conversion:

1. Preparation and Demolition (Day 1): The team will shut off the water supply. They carefully remove the old bathtub, faucet, and surrounding tile. Debris is bagged and hauled away. Tip: Ensure the workspace is sealed with plastic sheeting to contain dust.
2. Rough-In Plumbing (Day 1–2): This is the critical phase where the plumbing cost to add a shower to your old tub is primarily incurred. The plumber adjusts the hot and cold supply lines to the new height (usually 48 inches for the showerhead) and relocates the drain to match the new shower pan. They will pressure test the lines to ensure there are no leaks before closing up the walls.
3. Subfloor and Wall Preparation (Day 2): Any rotted wood is cut out and replaced. A new subfloor is installed if necessary. Walls are fitted with moisture-resistant cement backer board, not standard drywall.
4. Installation of Shower Base and Waterproofing (Day 3): The shower pan (base) is set in a bed of mortar to ensure it is perfectly level. Waterproofing membranes are applied to the floor and walls. This layer is vital; think of it as a giant raincoat for your bathroom structure.
5. Tiling and Grouting (Day 3–4): If you chose a tiled surround, the tiles are installed now. Once set, grout is applied. Note that grout needs time to cure, usually 24 hours, before exposure to water.
6. Fixture Installation and Final Touches (Day 5): The showerhead, valve trim, and glass doors are installed. The plumber turns the water back on and checks for proper flow and drainage speed. A final cleanup leaves your bathroom ready to use.

Frequently Asked Questions (FAQ)

1. Can I convert my tub to a shower without moving the plumbing?

Yes, it is possible if you choose a shower kit designed to fit the exact footprint of your existing tub. Many acrylic conversion kits are made to sit directly over the old drain location, minimizing the need to move pipes. This significantly reduces the plumbing cost to add a shower to your old tub. However, you may still need to adjust the faucet height.

2. How long does a typical tub-to-shower conversion take?

For a professional crew, a standard conversion usually takes 2 to 4 days. Custom tile work or complex plumbing rerouting can extend this to a week. DIY projects often stretch over several weekends depending on the homeowner’s availability and skill level.

3. Does converting a tub to a shower lower my home’s value?

Generally, no. In fact, many buyers prefer walk-in showers for their modern look and accessibility. However, if your home has only one bathroom and you remove the only bathtub, it might deter families with young children who need a tub for bathing kids. It is often wise to keep at least one tub in the house if space allows.

4. What is the difference between a shower pan and a tiled floor?

A shower pan is a pre-fabricated base (usually acrylic or fiberglass) that is watertight out of the box. It is cheaper and faster to install. A tiled floor involves building a custom mortar bed, applying a waterproof liner, and laying tiles. While more expensive and labor-intensive, a tiled floor offers unlimited design customization and can last longer if maintained properly.

5. Do I need a permit to replace my tub with a shower?

In most US jurisdictions, yes. Any alteration to the plumbing system, including moving drains or supply lines, typically requires a permit. Even if you aren’t moving pipes, some cities require permits for changing the fixture type. Always check with your local building department to avoid legal complications.

6. How can I reduce the cost of this project?

To save money, consider keeping the drain in its current location, choosing a pre-fabricated shower kit instead of custom tile, and doing the demolition yourself if you are physically able. Additionally, sourcing your own fixtures (faucets, showerheads) during sales can cut material costs, though you should verify with your plumber that they are willing to install customer-supplied materials.

Conclusion

Upgrading your bathroom by converting an old tub into a sleek, accessible shower is a fantastic investment in both your daily comfort and your home’s resale value. While the plumbing cost to add a shower to your old tub can vary based on materials and labor, understanding the breakdown empowers you to make informed decisions. Whether you choose a budget-friendly acrylic kit or a luxurious custom tile job, the key is to prioritize proper waterproofing and professional plumbing installation to avoid future disasters.

By addressing safety concerns and modernizing your space, you create a bathroom that serves your needs for years to come. Did you find this guide helpful for your renovation planning? Share this article on Facebook, Twitter, or Pinterest to help your friends and family navigate their own home improvement journeys!