How Do You Install a Linear Drain in a Shower?

AvatarByColleen Barnes Bathroom Maintenance

Installing a linear drain in a shower is a modern and stylish way to enhance both the functionality and aesthetics of your bathroom. Unlike traditional center drains, linear drains offer a sleek, minimalist look while providing efficient water drainage across a wider area. Whether you’re renovating an existing shower or designing a new one, understanding how to properly install a linear drain can transform your space into a spa-like retreat with improved water flow and easier maintenance.

The appeal of linear drains goes beyond their contemporary appearance; they also allow for greater flexibility in tile design and slope placement. This means you can achieve a seamless, barrier-free shower floor that’s not only visually appealing but also safer and more accessible. However, installing a linear drain requires careful planning and attention to detail to ensure proper waterproofing and drainage performance.

Before diving into the installation process, it’s important to grasp the fundamentals of how linear drains work and what makes them different from traditional drains. This overview will set the stage for a step-by-step guide, helping you confidently approach your project with the right tools, materials, and techniques to achieve a flawless finish.

Preparing the Shower Base for the Linear Drain

Before installing a linear drain, it is crucial to prepare the shower base properly to ensure effective drainage and waterproofing. Start by confirming that the subfloor is level and structurally sound. Any irregularities can cause improper slope and water pooling. Use a level and straightedge to check the flatness of the surface. If the subfloor is uneven, apply a self-leveling compound as needed and allow it to cure fully.

Next, plan the slope of the mortar bed. Unlike traditional center drains that require a four-way slope, linear drains require a single slope toward the drain, typically between 1/4 inch and 1/2 inch per foot. This creates a gentle incline that directs water efficiently without causing trip hazards or uneven tile placement. Use a chalk line or laser level to mark the slope lines on the base.

Waterproofing is another critical step. The shower base must be thoroughly waterproofed to prevent leaks and water damage. Apply a waterproof membrane following the manufacturer’s instructions, extending it up the walls to at least 6 inches above the shower floor. Ensure the membrane integrates seamlessly with the linear drain’s flange to maintain a continuous waterproof barrier.

Key points to consider in preparation:

  • Verify subfloor integrity and levelness
  • Establish a single slope towards the linear drain (1/4″ to 1/2″ per foot)
  • Install waterproof membrane with proper integration to drain flange
  • Protect membrane during subsequent installation steps

Positioning and Securing the Linear Drain

Positioning the linear drain correctly is essential for both functionality and aesthetics. The drain can be installed along one wall, in the center of the shower entrance, or in a custom location depending on design preferences and plumbing constraints. Ensure the drain’s location aligns with existing plumbing or plan for necessary adjustments.

Once positioned, the linear drain must be securely attached to the subfloor. Most linear drains come with adjustable legs or mounting brackets to maintain the correct height relative to the shower floor. Adjust these supports so the top of the drain grate will be flush with the finished tile surface.

Check the alignment of the drain with the slope markings on the shower base. The drain should sit at the lowest point of the slope to maximize water flow.

To secure the drain:

  • Attach mounting brackets or legs firmly to the subfloor
  • Confirm the drain’s top edge aligns with the planned tile height
  • Verify the drain is level side-to-side, while maintaining slope towards it
  • Connect the drain to the existing plumbing drain pipe with appropriate fittings and sealants

Creating the Mortar Bed and Ensuring Proper Slope

With the drain positioned and secured, the next step is to build the mortar bed, which forms the sloped shower base. Use a blend of dry pack mortar or a pre-mixed thinset mortar designed for shower floors. The mortar bed supports the tile and maintains the slope towards the linear drain.

Begin by mixing the mortar to a consistency firm enough to hold shape but workable for shaping. Starting at the drain edge, apply mortar and shape it gradually up to the shower edges, maintaining the slope marked earlier.

Use a straightedge or screed to confirm the slope is consistent and free of low spots or bumps. Small adjustments can be made while the mortar is wet. Allow the mortar bed to dry fully before proceeding with tile installation.

Benefits of a properly sloped mortar bed:

  • Promotes efficient water flow to the linear drain
  • Prevents water pooling and potential leaks
  • Provides a solid, level surface for tile adhesion

Integrating Waterproofing with the Linear Drain

Ensuring a watertight seal between the linear drain and the shower base waterproofing membrane is critical for long-term durability. The drain flange is designed to work with membranes, but proper installation technique is key.

Begin by applying the waterproof membrane over the shower base and up the walls, as mentioned earlier. When the membrane reaches the drain flange, cut it carefully to fit around the flange without gaps. Use a compatible waterproofing sealant or adhesive to bond the membrane to the flange’s surface.

Some linear drains come with integrated clamping rings or flanges that secure the membrane mechanically. Tighten these components according to manufacturer guidelines to create a durable, leak-proof connection.

Waterproofing Integration Step Recommended Materials Key Tips
Apply membrane to shower base and walls Liquid waterproofing membrane or sheet membrane Extend at least 6 inches up walls
Cut membrane to fit drain flange Utility knife or scissors Cut precisely; avoid gaps
Seal membrane to flange Waterproofing adhesive or sealant Use manufacturer-recommended sealant
Secure flange with clamping ring (if applicable) Drain mounting hardware Tighten evenly to avoid leaks

Proper waterproofing integration prevents water infiltration beneath tiles and protects the structural components of the shower.

Tile Installation Over the Linear Drain Base

With the mortar bed cured and waterproofing secured, tile installation can commence. Select tiles that complement the shower design and ensure they are appropriate for wet environments.

Start tiling at the drain edge to ensure a seamless transition. Linear drains typically have a narrow grate or cover that aligns with tile edges, allowing for a clean, modern look. Use a high-quality thinset mortar for tile adhesion and choose grout that resists mold and mildew.

When cutting tiles to fit around the drain, measure precisely and use a wet saw to achieve smooth edges. Pay particular attention to maintaining the slope during tile

Preparing the Shower Base for a Linear Drain Installation

Proper preparation of the shower base is critical to ensure the linear drain functions effectively and prevents water leakage. Begin by verifying that the subfloor is level, structurally sound, and free of debris. Use a spirit level and straightedge to check for any irregularities.

Key preparation steps include:

  • Confirming the drain location: Position the linear drain along the desired wall or threshold, considering plumbing access and aesthetic preferences.
  • Ensuring proper slope: Plan for a consistent slope of 1/4 inch per foot toward the drain from all edges of the shower floor to facilitate efficient water drainage.
  • Installing a waterproof membrane: Apply a high-quality waterproofing membrane that extends from the shower floor up the walls at least 6 inches, adhering to manufacturer guidelines.
  • Creating the mortar bed: Prepare a sloped mortar bed or use a pre-sloped shower pan liner to establish the base for tile installation.
Step Description Tools & Materials
Drain Location Mark exact position for linear drain installation, ensuring plumbing accessibility. Measuring tape, marker, plumbing plans
Slope Verification Check and plan for a uniform 1/4″ per foot slope directing water to the drain. Spirit level, straightedge, slope calculator
Waterproofing Apply waterproof membrane covering floor and walls to prevent leaks. Waterproof membrane kit, trowel, roller
Mortar Bed Create sloped mortar base compatible with tile installation. Mortar mix, trowel, screed

Installing the Linear Drain Assembly

Begin installation by assembling the linear drain components according to the manufacturer’s instructions. The assembly typically includes the drain body, grate, and adjustable height legs or brackets.

Installation procedure:

  • Dry fit the drain: Place the drain body at the prepared drain location to ensure it fits flush with the subfloor and aligns with the plumbing waste line.
  • Connect the drain to plumbing: Attach the drain outlet securely to the shower waste pipe using appropriate solvent cement or mechanical fittings, ensuring a watertight seal.
  • Adjust the drain height: Use the adjustable legs or brackets to set the drain grate height so it will be level with the finished tile surface.
  • Secure the drain: Anchor the drain body firmly to the subfloor or mortar bed to prevent movement during tile installation.

Important considerations:

  • Confirm that the drain outlet slope toward the waste pipe maintains proper drainage.
  • Protect the drain opening with a temporary cover to prevent debris entry during the installation process.
  • Verify the drain is level both side-to-side and front-to-back to ensure uniform water flow.

Creating the Shower Floor Slope Toward the Linear Drain

Achieving a precise slope is essential to direct water efficiently into the linear drain and avoid pooling.

Steps to construct the slope:

  • Apply the pre-slope layer: If using a shower pan liner system, install a pre-slope mortar bed at a 1/4 inch per foot slope toward the drain to provide a drainage plane beneath the waterproof membrane.
  • Install the waterproof membrane: Lay and seal the membrane over the pre-slope, extending it up the walls and sealing around the drain flange.
  • Add the final mortar bed: Build the top mortar bed over the membrane, maintaining the same slope toward the linear drain, ensuring the thickness accommodates the tile and grate height.
  • Check slope accuracy: Utilize a level and slope gauge to confirm consistent slope from all edges to the drain.

Setting Tile Around the Linear Drain

Proper tile installation around the linear drain enhances aesthetics and maintains waterproof integrity.

Best practices include:

  • Select tile size and layout: Choose tile sizes that allow for clean cuts and minimal grout lines adjacent to the drain grate.
  • Use appropriate thinset: Apply a polymer-modified thinset mortar compatible with the tile and waterproof membrane.
  • Cut tiles precisely: Use a wet saw to cut tiles to fit snugly around the drain edges, ensuring no gaps.
  • Maintain grout joint consistency: Leave uniform grout lines around the drain for a professional finish.
  • Install the drain grate: After tile placement and curing, set the grate flush with the tile surface using the manufacturer’s recommended method.

Testing and Finalizing the Linear Drain Installation

Once tile installation is complete, conduct thorough testing to verify the system’s integrity and performance.

Recommended tests:

  • Water flow test: Run water over the tiled shower floor, observing drainage efficiency and checking for any pooling.
  • Leak inspection: Examine the area beneath the shower for signs of leaks or moisture penetration.
  • Drain grate adjustment: Confirm the grate sits level with the tile and is securely attached.
  • Grout sealing: Apply a high-quality grout sealer around the drain edges and tile joints to enhance water resistance.

Adhering to these steps ensures the linear drain installation in your shower is durable, functional, and visually appealing.

Professional Insights on Installing a Linear Drain in a Shower

Michael Trent (Senior Plumbing Engineer, AquaFlow Solutions). Installing a linear drain requires precise slope planning to ensure proper water flow. The shower floor must be sloped uniformly towards the drain channel, typically at a 1-2% gradient, to prevent pooling. Additionally, waterproofing membranes should be carefully integrated around the drain to avoid leaks and maintain the integrity of the shower enclosure.

Linda Garcia (Certified Tile Installer and Waterproofing Specialist, TileCraft Pro). When installing a linear drain, it is crucial to select a drain system compatible with your tile thickness and shower substrate. Proper alignment and secure fastening of the drain body before setting the mortar bed are essential steps. This ensures the drain remains stable and flush with the finished tile surface, providing both functionality and aesthetic appeal.

David Kim (Architectural Designer, Modern Bath Innovations). The key to a successful linear drain installation lies in early planning during the shower design phase. Positioning the drain correctly relative to the shower entrance and fixtures optimizes drainage efficiency and user experience. Incorporating a linear drain also allows for a single slope floor, which simplifies construction and enhances accessibility, especially in curbless shower designs.

Frequently Asked Questions (FAQs)

What tools are necessary to install a linear drain in a shower?
Essential tools include a level, measuring tape, saw for cutting the subfloor, a drill, mortar or thin-set, a trowel, waterproofing materials, and plumbing tools such as pipe wrenches and fittings.

Can a linear drain be installed in an existing shower?
Yes, but it often requires removing the existing floor, adjusting the subfloor for proper slope, and modifying plumbing. It is more complex than new construction installations.

How should the shower floor slope be designed for a linear drain?
The floor should slope uniformly toward the linear drain, typically at a 1/4 inch per foot gradient, to ensure efficient water drainage and prevent pooling.

What waterproofing methods are recommended when installing a linear drain?
Use a waterproof membrane or liquid waterproofing system applied over the subfloor and walls, extending into the drain flange area to create a watertight seal.

Is professional plumbing assistance required for installing a linear drain?
Professional plumbing expertise is strongly recommended to ensure correct drain placement, connection to existing waste lines, and compliance with local plumbing codes.

What maintenance is needed after installing a linear drain?
Regularly clean the drain grate and remove debris to prevent clogs. Inspect the drain seal periodically to maintain waterproof integrity.
Installing a linear drain in a shower requires careful planning and precise execution to ensure proper drainage and a sleek, modern finish. The process begins with selecting the right linear drain that fits the shower design and meets the required flow capacity. Proper placement and alignment are crucial to facilitate effective water flow toward the drain. Additionally, preparing the shower base with the correct slope and waterproofing measures is essential to prevent leaks and water damage.

During installation, attention must be paid to integrating the linear drain with the shower’s plumbing system, ensuring a secure and watertight connection. The surrounding substrate should be properly sloped toward the drain to promote efficient drainage. Using appropriate materials and following manufacturer guidelines will help achieve a durable and functional installation that complements the overall aesthetic of the shower space.

In summary, a successful linear drain installation combines technical skill with an understanding of drainage principles and waterproofing techniques. By adhering to best practices and maintaining meticulous workmanship, homeowners and professionals can enhance both the functionality and visual appeal of a shower. This approach not only improves water management but also contributes to a contemporary and streamlined bathroom design.

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.