How Do You Replace a Shower with a Bathtub?

AvatarByColleen Barnes Shower Hardware

Replacing a shower with a bathtub can transform your bathroom into a more relaxing and versatile space, offering a perfect blend of comfort and style. Whether you’re looking to create a spa-like retreat, accommodate young children, or simply enhance your home’s value, making this switch is a popular renovation choice. However, the process involves more than just swapping fixtures—it requires careful planning, the right tools, and a clear understanding of your bathroom’s layout and plumbing.

This transition from shower to bathtub is a rewarding project that can breathe new life into your bathroom, but it also comes with its unique set of challenges. From selecting the ideal bathtub style to ensuring proper waterproofing and drainage, there are several important factors to consider. Understanding these elements upfront will help you avoid common pitfalls and ensure a smooth installation.

In the following sections, we’ll explore the essential steps and considerations involved in replacing a shower with a bathtub. Whether you’re a DIY enthusiast or planning to hire a professional, this guide will provide you with the foundational knowledge needed to make informed decisions and achieve a successful bathroom makeover.

Preparing the Bathroom for Installation

Before removing the existing shower and installing a bathtub, thorough preparation of the bathroom space is crucial to ensure a smooth transition. Start by clearing the area, removing any personal items, shower curtains, and accessories. Protect adjacent surfaces such as floors and walls with drop cloths or plastic sheeting to prevent damage from dust, debris, or water.

Next, turn off the water supply to the bathroom to avoid leaks or flooding during removal and installation. Verify that the water is fully shut off by opening a faucet and checking for flow cessation. Disconnect the water lines connected to the shower fixtures using appropriate plumbing tools.

Evaluate the current shower enclosure’s dimensions and structure. Measure the length, width, and height of the shower area to determine if modifications are necessary to accommodate the bathtub. Bathtubs typically require more space and may necessitate wall adjustments or reinforcement.

Check the condition of the subfloor and wall studs for any signs of water damage, mold, or rot. Repair or replace compromised materials to provide a stable foundation for the new bathtub. This step is critical to prevent future structural issues.

Removing the Existing Shower

Careful removal of the existing shower is a multi-step process that involves detaching fixtures, demolition, and cleanup. Begin by removing the shower doors, curtain rods, and any shelving or hardware attached to the walls.

Next, detach the showerhead, faucet, and plumbing fixtures from the wall. Use wrenches or pipe cutters as needed, taking care not to damage the plumbing system if it will be reused. Cap exposed water lines temporarily to prevent leaks during demolition.

To remove the shower walls or tiles, score grout lines with a utility knife and use a chisel or hammer to pry off tiles or panels. If the shower enclosure includes a pre-fabricated unit, carefully dismantle it by unscrewing brackets and pulling the unit away from the wall.

Once the walls are removed, detach the shower pan or base. Depending on the type, it may be secured with adhesive, screws, or mortar. Use a pry bar to lift and remove the base, being cautious of sharp edges and debris.

Dispose of all materials responsibly, separating recyclable items from waste. Clean the area thoroughly to prepare for bathtub installation.

Modifying Plumbing and Drainage

Installing a bathtub often requires modifications to existing plumbing and drainage systems to accommodate different dimensions and configurations. Bathtubs generally have a larger drain opening and may require repositioning of water supply lines.

Begin by assessing the location of the current shower drain relative to the bathtub drain requirements. Bathtub drains are commonly placed at one end, whereas shower drains can be centered. Adjust the drain location by cutting into the subfloor and repositioning the drainpipe as necessary.

Ensure that the plumbing connections for hot and cold water lines are compatible with the bathtub faucet. You may need to extend or reroute these lines to match the new fixture’s layout. Use appropriate fittings and secure connections to prevent leaks.

It is essential to verify that the drainage slope meets local building codes, typically requiring a minimum slope of 1/4 inch per foot to ensure proper water flow. Improper drainage can lead to standing water and damage.

Consider installing a bathtub overflow drain if the new tub does not have one pre-installed. This safety feature prevents water from spilling over the edge in case of accidental overfilling.

Plumbing Component Shower Bathtub Modification Required
Drain Location Typically centered Usually at one end Yes – reposition drain pipe
Water Supply Lines Lower height, spaced for shower valve Higher height, spaced for tub faucet and spout Often yes – extend or reroute lines
Drain Pipe Size 1.5 inches 2 inches or more May need upsizing for tub drain
Overflow Drain Usually none Standard feature Install if missing

Installing the Bathtub

With the plumbing and structural modifications complete, proceed to install the bathtub. Position the tub in the prepared space, verifying that it fits securely and aligns with the drain and water supply connections.

Level the bathtub using a spirit level, adjusting as necessary by shimming underneath the base. A level tub prevents water pooling and ensures proper drainage. Secure the tub to the wall studs with screws or brackets according to the manufacturer’s instructions.

Connect the drain assembly to the bathtub drain and attach the overflow drain if applicable. Use plumber’s putty or silicone sealant to create watertight seals around the drain fittings. Connect the bathtub faucet and spout to the water supply lines, checking all connections for leaks.

After installation, test the tub by filling it with water and draining it to confirm proper function. Inspect all plumbing joints carefully for signs of leakage. Make any necessary adjustments before proceeding to finish the walls and flooring.

Finishing Touches and Waterproofing

Once the bathtub is securely installed and plumbing tested, focus on finishing the surrounding area to ensure durability and aesthetic appeal. Waterproofing is critical to prevent moisture infiltration that can cause mold and structural damage.

Apply a waterproof membrane or backer board to the walls surrounding the bathtub. Use materials specifically designed for wet environments to maintain long-term protection. Seal all joints and corners with waterproof tape and silicone caulk.

Install tiles, panels, or other wall finishes over the waterproof barrier, ensuring that edges overlap the tub flange to channel water

Assessing the Existing Shower Space and Plumbing

Before beginning the replacement of a shower with a bathtub, a thorough assessment of the existing space and plumbing setup is crucial. This step ensures compatibility and identifies any modifications required to accommodate the new bathtub.

Key aspects to evaluate include:

  • Dimensions of the existing shower area: Measure the length, width, and height to confirm the bathtub will fit comfortably.
  • Drain location and plumbing configuration: Determine if the current drain aligns with the bathtub drain or if repositioning is necessary.
  • Water supply lines: Check the placement and condition of hot and cold water lines to ensure compatibility with the bathtub faucet and spout.
  • Wall and floor condition: Inspect for water damage, mold, or structural issues that may require remediation before installation.
Element Assessment Criteria Potential Modification
Space Dimensions Confirm bathtub fits within shower enclosure dimensions Expand shower area or select a smaller tub if necessary
Drain Location Position relative to bathtub drain outlet Re-route drain plumbing or select tub with matching drain placement
Water Supply Lines Compatibility with bathtub faucet and spout Extend or relocate supply lines as needed
Wall and Floor Condition Presence of water damage or mold Repair or replace wall studs, backer boards, and flooring

Removing the Existing Shower Fixtures and Surround

Safely dismantling the existing shower fixtures and surround is the next step, requiring attention to detail to avoid damaging plumbing or structural elements.

Follow these professional guidelines:

  • Turn off the water supply: Shut off the main water valve or localized valves feeding the shower.
  • Remove showerhead and faucet handles: Unscrew and carefully detach, keeping hardware organized for potential reuse or disposal.
  • Detach shower enclosure or tiles: For tiled surrounds, use appropriate tools such as a utility knife and pry bar to remove tiles and cement board without damaging the wall studs.
  • Disconnect drain assembly: Remove the drain cover and disconnect the drain trap from underneath the shower base.
  • Extract shower pan or base: Cut through any caulking and fasteners holding the base; lift out carefully to preserve the subfloor.

Proper disposal of demolition debris is necessary, especially if materials contain mold or hazardous substances. Always wear protective gear such as gloves, safety glasses, and a dust mask during removal.

Adjusting Plumbing for Bathtub Installation

Installing a bathtub typically requires repositioning or upgrading plumbing to accommodate the tub’s drain and faucet configuration. This stage often demands professional plumbing expertise to ensure compliance with local codes and functional performance.

Consider the following adjustments:

  • Drain relocation: Bathtub drains are usually positioned differently than shower drains. The drain pipe may need to be shifted within the subfloor to align with the tub’s drain outlet.
  • Supply line modifications: Faucet and spout installations often require different supply line heights and connections than showers. Supply valves may need to be extended or moved.
  • Install new drain assembly: Bathtubs require a specific drain and overflow assembly that connects both the drain and overflow openings to the waste line.
  • Verify venting: Proper venting of the drain system prevents slow drainage and sewer gas intrusion. Ensure vent pipes are intact and correctly configured.
Plumbing Component Typical Shower Setup Bathtub Requirements Modification Actions
Drain Pipe Positioned at shower base center or corner Located at tub drain outlet; includes overflow pipe Re-route drain pipe; install overflow drain assembly
Water Supply Lines Shower valve with single or dual control Separate faucet and spout connections Relocate or extend supply lines as needed
Venting Standard vent pipe for shower drain Proper venting for tub drain and overflow Inspect and adjust venting if necessary

Installing the Bathtub and Surround

With plumbing prepared, the bathtub installation can proceed, followed by the application of a suitable surround or wall finish.

Steps for professional

Professional Insights on How To Replace A Shower With A Bathtub

Jessica Nguyen (Certified Bathroom Remodeler, HomeStyle Renovations). Replacing a shower with a bathtub requires careful planning, especially regarding plumbing adjustments and waterproofing. It is essential to ensure that the existing drain location aligns with the new bathtub’s drain to avoid extensive pipe rerouting. Additionally, selecting a bathtub that fits the space without compromising bathroom accessibility is critical for both functionality and aesthetics.

Dr. Michael Thompson (Licensed Plumbing Engineer, AquaFlow Consultants). From a plumbing perspective, the key challenge in replacing a shower with a bathtub lies in managing water flow and drainage capacity. Bathtubs typically require a larger drain and overflow system than showers. Proper venting and ensuring the water supply lines are compatible with the new fixture will prevent future leaks and maintain optimal water pressure.

Linda Perez (Interior Designer specializing in Bathroom Renovations, Luxe Living Interiors). When converting a shower to a bathtub, it’s important to consider the overall design harmony and user experience. Bathtubs often become a focal point, so integrating tile work, lighting, and storage solutions around the tub can enhance both comfort and style. Additionally, accessibility features such as grab bars or non-slip surfaces should be incorporated to ensure safety without sacrificing elegance.

Frequently Asked Questions (FAQs)

What are the main steps involved in replacing a shower with a bathtub?
The process includes removing the existing shower, modifying plumbing to accommodate the bathtub, installing the tub, waterproofing the area, and finishing with tiling and fixtures.

Do I need to hire a professional plumber for this replacement?
Yes, a professional plumber is recommended to ensure proper drainage, water supply connections, and compliance with local building codes.

How long does it typically take to replace a shower with a bathtub?
The project usually takes 3 to 5 days, depending on the complexity of plumbing adjustments and finishing work.

Can I use the existing shower space for a bathtub without major renovations?
In some cases, yes, if the space dimensions and plumbing align with standard bathtub sizes; otherwise, structural modifications may be necessary.

What are the common challenges faced during this replacement?
Challenges include adjusting plumbing lines, ensuring proper waterproofing, managing space constraints, and meeting building regulations.

How much does it generally cost to replace a shower with a bathtub?
Costs vary widely but typically range from $1,500 to $5,000, depending on materials, labor, and any additional remodeling required.
Replacing a shower with a bathtub involves careful planning, precise measurements, and a clear understanding of plumbing and installation requirements. The process typically begins with removing the existing shower unit and assessing the plumbing layout to ensure compatibility with a bathtub. Proper waterproofing and drainage adjustments are essential to prevent future water damage and ensure the bathtub functions correctly. Selecting the right bathtub size and style that fits the space and meets user needs is also a critical step.

Professional expertise is often recommended for this type of renovation due to the complexity of plumbing modifications and the need for proper sealing and tiling. Attention to detail during installation, including securing the bathtub and ensuring all connections are leak-free, will contribute to a durable and aesthetically pleasing result. Additionally, compliance with local building codes and regulations should be verified to avoid any legal or safety issues.

Ultimately, replacing a shower with a bathtub can enhance the functionality and value of a bathroom when executed correctly. By following a systematic approach and considering all technical aspects, homeowners can achieve a successful transformation that meets their bathing preferences and improves overall bathroom comfort.

Author Profile

Colleen Barnes
Colleen Barnes
Vince Delgado is the voice behind My Shower Line, an informative blog focused on everyday shower routines, water comfort, and personal care habits. Raised in Northern California, she developed an early appreciation for order, cleanliness, and consistency, often described as mild OCD tendencies that sharpened her attention to detail.

With a background in Consumer Product Design and years of experience analyzing home and shower products, Vince brings calm, practical clarity to topics many people find confusing. Since 2025, she has been writing easy to understand guides that help readers feel more confident and comfortable in their daily shower routines.