How Do You Install a Bathtub Shower Combo Step by Step?

AvatarByColleen Barnes Shower Hardware

Installing a bathtub shower combo is a smart and stylish way to maximize space and functionality in any bathroom. Whether you’re renovating an existing bathroom or designing a new one, this versatile fixture offers the perfect blend of convenience and comfort, allowing you to enjoy both relaxing baths and quick showers without sacrificing room. Understanding the basics of how to install a bathtub shower combo can empower you to take on this project with confidence, transforming your bathroom into a more practical and inviting space.

The process of installing a bathtub shower combo involves a combination of plumbing, carpentry, and finishing skills, making it a rewarding challenge for DIY enthusiasts and professionals alike. From selecting the right unit to ensuring proper waterproofing and drainage, each step plays a crucial role in achieving a durable, leak-free installation. While the task may seem daunting at first, breaking it down into manageable stages helps simplify the journey and ensures a successful outcome.

In this article, we’ll explore the key considerations and essential steps involved in installing a bathtub shower combo. Whether you’re upgrading an outdated tub or adding a shower option to a compact bathroom, understanding the installation process will help you make informed decisions and avoid common pitfalls. Get ready to dive into a comprehensive guide that will prepare you to create a beautiful, functional bathroom centerpiece.

Preparing the Installation Area

Before installing a bathtub shower combo, it is essential to prepare the installation area thoroughly. Begin by turning off the water supply to avoid any leaks or water damage during the installation process. Remove any existing fixtures, including the old bathtub, shower walls, and plumbing fittings. Carefully inspect the subfloor and wall studs for any signs of water damage or mold and repair as needed to ensure a stable and safe foundation.

Ensure the plumbing rough-ins are correctly positioned according to the new bathtub shower combo specifications. This includes the water supply lines, drain, and overflow pipes. If adjustments are necessary, this is the time to make them, preferably with the assistance of a licensed plumber.

Clear the workspace of debris and dust to maintain a clean environment, which will aid in precise installation. Use protective coverings on floors and adjacent surfaces to prevent damage during the process.

Installing the Bathtub Base

The bathtub base serves as the foundation of the combo unit and must be installed with precision. Place the bathtub in the designated area to check for a proper fit. Ensure the base is level using a carpenter’s level, as an uneven base can lead to drainage problems and structural stress.

If the base requires shimming, use waterproof shims to adjust the level. Once aligned, secure the tub to the wall studs using the manufacturer’s recommended fasteners. Typically, this involves screwing the flange of the tub into the studs.

Connect the drain assembly to the bathtub drain outlet, ensuring a watertight seal. It is advisable to apply plumber’s putty or a silicone sealant around the drain flange to prevent leaks. Attach the overflow pipe and test for proper alignment.

Installing the Shower Walls

Shower walls can be installed using prefabricated panels or custom tile work. Prefabricated panels are generally easier and quicker to install, while tile offers more design flexibility but requires additional waterproofing.

When installing prefabricated shower walls:

  • Begin at the corner and work outward.
  • Apply a waterproof adhesive or sealant to the back of each panel.
  • Press firmly against the studs or backer board, ensuring panels are flush.
  • Use trim pieces to cover seams and edges for a finished look.

For tiled shower walls:

  • Install a cement backer board over the studs for a moisture-resistant surface.
  • Apply a waterproof membrane to the backer board before tiling.
  • Lay tiles starting from the bottom center, using spacers to maintain even grout lines.
  • After the tiles set, apply grout and seal the grout lines to prevent water penetration.

Connecting the Plumbing Fixtures

After securing the bathtub and shower walls, connect the plumbing fixtures. This includes the faucet, shower valve, spout, and showerhead. Follow these steps for a professional installation:

  • Attach the shower valve to the supply lines, ensuring hot and cold water lines correspond correctly.
  • Connect the bathtub spout to the outlet pipe, using Teflon tape on threaded connections to prevent leaks.
  • Install the showerhead onto the shower arm, again using Teflon tape for a secure seal.
  • Test all connections for leaks by turning the water supply on and operating both the tub faucet and shower.

Sealing and Finishing Touches

Proper sealing is crucial to prevent water damage and mold growth. Apply a high-quality silicone caulk around all joints where the bathtub meets the walls and floor. Pay special attention to corners and seams where water is most likely to infiltrate.

Additionally, install any trim pieces or edge protectors recommended by the manufacturer to enhance durability and aesthetics. Attach the shower curtain rod or door frame, depending on your chosen enclosure.

Inspect all fixtures and seals one last time to ensure a tight, watertight installation. Clean the surfaces to remove any debris or adhesive residue, leaving the bathtub shower combo ready for use.

Step Key Considerations Tools/Materials Needed
Prepare Installation Area Turn off water, remove old fixtures, check for damage Wrenches, screwdrivers, protective coverings
Install Bathtub Base Level tub, secure to studs, connect drain Level, waterproof shims, screws, plumber’s putty
Install Shower Walls Apply adhesive/membrane, align panels or tile Adhesive, backer board, tiles, grout, spacers
Connect Plumbing Fixtures Match hot/cold lines, use Teflon tape, test for leaks Wrenches, Teflon tape, plumbing fittings
Seal and Finish Apply silicone caulk, install trim, clean surfaces Silicone caulk, caulking gun, cleaning supplies

Preparing the Installation Site

Before installing a bathtub shower combo, thoroughly prepare the designated area to ensure a smooth installation process and a secure fit. Begin by measuring the available space to confirm that the new unit will fit properly. Remove any existing fixtures, including old tubs, shower surrounds, or plumbing components, taking care to avoid damaging surrounding walls or floors.

Assess the condition of the subfloor and wall studs. The subfloor must be level, dry, and free of damage; reinforce or repair as necessary. Ensure wall studs are properly spaced, typically 16 inches on center, to support the new unit and any additional accessories such as grab bars or shelving. Verify that plumbing rough-ins—water supply lines and drain outlets—are correctly positioned to align with the new bathtub shower combo. Adjust plumbing if needed before proceeding.

Use a level and square to check the flatness and alignment of the floor and walls. Any unevenness can cause improper sealing and water leakage. Install a vapor barrier or moisture-resistant drywall (green board or cement board) on the walls surrounding the tub area to protect against moisture damage.

Installing the Bathtub Base

The bathtub base is the foundational element of the combo and must be installed with precision to ensure stability and proper drainage.

  • Position the Base: Dry fit the bathtub base in the prepared space to verify fit and alignment with plumbing connections.
  • Level the Base: Use shims beneath the base where necessary to achieve a perfectly level position, checking with a spirit level across multiple points.
  • Connect Drain Assembly: Attach the drain and overflow assembly to the bathtub before placing it permanently. Ensure all seals and gaskets are correctly positioned to prevent leaks.
  • Secure the Base: Depending on the model, secure the base to wall studs using manufacturer-recommended fasteners or adhesives. Avoid overtightening, which can deform the tub.
  • Seal the Perimeter: Apply a bead of high-quality, mildew-resistant silicone caulk along the edges where the tub meets the floor and walls to prevent water infiltration.
Step Action Tools/Materials Needed
Position Base Dry fit to check placement and plumbing alignment Measuring tape, level
Level Base Use shims to achieve levelness Spirit level, wood shims
Connect Drain Install drain and overflow assembly with proper seals Plumber’s putty, wrench, gaskets
Secure Base Fasten base to studs or secure with adhesive Screwdriver, screws, adhesive
Seal Perimeter Apply silicone caulk around edges Silicone caulk, caulk gun

Installing the Shower Walls and Fixtures

After securing the bathtub base, proceed to install the shower walls and fixtures, ensuring a watertight enclosure and functional shower setup.

Begin by installing the shower wall panels or tiles as per the product specifications. For prefabricated shower wall kits, carefully align panels and secure them to the wall studs using corrosion-resistant screws or adhesive recommended by the manufacturer. If tiling, install cement board backer and waterproof membrane before applying tile.

Seal all joints between panels or tiles with waterproof sealant or grout. Pay special attention to corners and vertical seams where water infiltration is most likely.

Next, install the shower fixtures including the valve, spout, and showerhead. Connect the water supply lines to the shower valve, ensuring all connections are tight and leak-free. Use plumber’s tape on threaded connections to enhance sealing.

Mount the shower valve at a comfortable height, typically 38 to 48 inches from the tub floor. Install the spout at a height that allows easy access for filling the bathtub. Attach the showerhead at a height of approximately 72 to 78 inches, adjusted for user preference.

Test all fixtures for proper water flow and check for leaks before finishing the wall enclosure. Adjust as necessary to guarantee optimal performance.

Final Sealing and Finishing Touches

Completing the installation requires thorough sealing and detailed finishing to protect the structure and enhance usability.

Apply a continuous bead of silicone caulk along all seams where the bathtub meets the shower walls and the floor. This prevents water from seeping into gaps and causing mold or structural damage. Smooth the caulk with a wet finger or caulk finishing tool for a clean appearance.

Install any additional accessories such as grab bars, soap dishes, or shelving according to manufacturer guidelines and local building codes. These elements should be securely anchored into studs or blocking to ensure safety.

Check that all drain connections are sealed and functioning properly. Run water through the system, including the shower and tub spout, to confirm proper drainage and absence of leaks.

Clean the entire installation area to remove dust, debris, and excess caulk. Allow all sealants to cure fully as specified by the manufacturer

Professional Perspectives on Installing a Bathtub Shower Combo

Jessica Martinez (Licensed Plumbing Contractor, AquaFlow Services). Installing a bathtub shower combo requires precise plumbing adjustments to ensure proper water flow and drainage. It is essential to verify that the existing water supply lines can accommodate both fixtures without pressure loss. Additionally, using corrosion-resistant materials for connections will enhance the longevity of the installation and prevent leaks.

David Chen (Certified Home Remodeler, RenovatePro). When installing a bathtub shower combo, careful planning of the waterproofing system is critical. Properly sealing the walls and tub edges with high-quality waterproof membranes and caulking prevents water damage and mold growth. Also, selecting a showerhead and faucet combination that fits the space ergonomically improves both functionality and user comfort.

Linda Harper (Architectural Designer, BathSpace Innovations). The integration of a bathtub shower combo should consider both spatial layout and user accessibility. Positioning the combo to maximize natural light and ensuring sufficient clearance around the unit enhances the overall bathroom experience. Furthermore, incorporating anti-slip surfaces and grab bars promotes safety without compromising aesthetic appeal.

Frequently Asked Questions (FAQs)

What tools are required to install a bathtub shower combo?
Essential tools include a tape measure, level, drill, adjustable wrench, pipe wrench, plumbing snake, caulking gun, and safety equipment such as gloves and goggles.

Can I install a bathtub shower combo myself, or should I hire a professional?
While experienced DIYers can install a bathtub shower combo, it is recommended to hire a licensed plumber or contractor to ensure proper installation, especially for plumbing and waterproofing.

How long does it typically take to install a bathtub shower combo?
Installation time varies but generally ranges from one to three days, depending on the complexity of plumbing, wall preparation, and finishing work.

What plumbing considerations are important when installing a bathtub shower combo?
Ensure proper drain alignment, adequate water pressure, and correct installation of valves and fixtures to prevent leaks and ensure efficient water flow.

How do I waterproof the area around the bathtub shower combo?
Use a waterproof membrane or backer board behind tiles, apply waterproof sealant around edges, and install proper flashing to prevent water damage.

What maintenance is required after installing a bathtub shower combo?
Regularly inspect caulking and grout for cracks, clean fixtures to prevent buildup, and check for leaks to maintain functionality and prolong the unit’s lifespan.
Installing a bathtub shower combo requires careful planning, precise measurements, and the right tools to ensure a successful and durable setup. The process typically involves removing the existing fixtures, preparing the plumbing connections, securing the tub in place, and properly sealing all joints to prevent leaks. Attention to detail during each step, from leveling the tub to installing the showerhead and curtain rods, is essential to achieve a functional and aesthetically pleasing result.

Understanding the importance of waterproofing and proper drainage cannot be overstated, as these factors directly impact the longevity and safety of the installation. Utilizing quality materials and following manufacturer guidelines will help avoid common issues such as water damage or mold growth. Additionally, ensuring compliance with local building codes and regulations is critical to guarantee that the installation meets safety standards.

Ultimately, while installing a bathtub shower combo can be a manageable DIY project for those with moderate plumbing and carpentry skills, consulting or hiring a professional plumber or contractor is advisable for complex situations. This approach ensures the installation is done efficiently, safely, and up to code, providing peace of mind and long-term satisfaction with the bathroom upgrade.

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.