How to Install a Linear Shower Drain


Installing a linear shower drain is an easy way to create a sleek, modern look in your bathroom while also improving drainage. A linear drain runs along the width of the shower floor, providing an uninterrupted line of drainage that is both aesthetically pleasing and highly functional.

While a standard shower drain collects water at a single point, a linear drain system allows water to enter along the full length of the channel. This helps prevent water from pooling and enables more efficient drainage. Linear drains are especially well-suited for large, open showers such as walk-in showers and steam showers. They promote proper drainage while creating a streamlined, contemporary style.

Installing a linear shower drain is a relatively simple project that most DIYers can complete in a weekend. With careful planning and the right materials, you can add this stylish drain system while avoiding leaks and other problems down the road. This guide will walk you through the entire process step-by-step, from layout planning to connecting the piping. Follow along to learn proper techniques and helpful tips to complete a successful linear drain installation.

Gather the Necessary Materials

Before starting any project, it’s important to make sure you have all the required materials on hand. Installing a linear shower drain requires the following key items:

  • Linear shower drain system – The drain kit will include the drain channel, drain body, removable perforated grate, and mounting hardware. Choose a drain width that matches your planned shower size.
  • PVC pipe and fittings – PVC is the most common drain pipe material. You’ll need straight lengths, elbows, and tees to connect to the drain body.
  • Drainage mortar – This premixed blend bonds drain components and slopes the shower floor.
  • Waterproofing membrane – An essential barrier applied under tile that seals out moisture.
  • Thinset mortar – Used to set shower tiles over the waterproofing membrane.
  • Tile and grout – Select shower tiles that complement the linear drain design.
  • Silicone caulk – Seals all seams and gaps after installation to prevent leaks.
  • Tools – Utility knife, putty knife, mixing paddle, grout float, sponge, buckets, tape measure, level, and safety gear.

Also have any additional plumbing supplies on hand that will be needed to connect to existing drain lines.

Plan the Layout

The first step is to map out exactly where the linear drain will be located. It should be positioned several inches away from the entrance threshold. Avoid placing it directly in front of the shower entryway where it would easily get clogged by debris entering from outside the shower.

account for the size of your planned shower tiles. The drain channel should be centered under full tiles and away from any tile cuts less than half a tile wide. This provides the neatest appearance. Place the drain so an equal number of full tiles border each side.

Determine the exact position along the width of the shower. In most cases, centering the drain provides ideal slope and drainage. However, an off-center placement can work as well. Just be sure to maintain a minimum slope of 1/4-inch per foot running to the drain.

Mark the drain location on the subfloor so it can be properly aligned during installation. The drain pipe will need to tie into existing plumbing under the subfloor, so plan your layout accordingly.

Install the Linear Drain

With your layout mapped, it’s time to move on to drain installation. Carefully follow the manufacturer’s instructions for assembly and always use the provided hardware. Here is the basic process:

Step 1: Cut an Opening for the Drain Pipe

  • The drain pipe needs to penetrate down through the subfloor to connect to plumbing below.
  • Cut a hole at the planned location based on the drain body diameter (typically 4” or 6″).
  • Cut the hole slightly larger than required for easy fit and alignment.

Step 2: Attach the Drain Body

  • Fasten the drain body level and oriented properly over the hole using screws.
  • The weep holes on the bottom must align with the opening for proper drainage.
  • Avoid exterior walls and position between 16” floor joists.

Step 3: Assemble the Drain Channel

  • Insert the perforated drain grate into the channel opening.
  • Place the drain channel so it interlocks with the drain body.
  • Secure tightly using provided bolts inserted through pre-drilled holes.

Step 4: Water Test the Assembly

  • Temporarily attach a drainage pipe to test for leaks.
  • Plug the drain outlet and fill the assembly with water.
  • Inspect closely and fix any areas that leak.
  • Drain the assembly fully after testing.

The linear drain body should now be firmly affixed and ready for waterproofing and tile installation. Avoid stepping directly on the drain components during further construction.

Install the Mortar Base

With the linear drain securely installed, the next step is to slope the shower floor. This provides proper drainage down to the drain system.

A mortar bed is installed on top of the subfloor to create this slope. Drainage mortar is specifically designed for shower applications. It builds the base while gradually angling down to the drain location.

Follow these steps to complete the mortar installation:

Step 1: Dam the Drain Opening

  • Stuff foam backer rod or a plastic bag in the drain opening.
  • This prevents mortar from clogging drain weep holes.
  • Seal any gaps around the drain body with duct tape.

Step 2: Apply the Mortar

  • Mix the mortar per package directions (typically add water to powder).
  • Apply first layer of mortar 1/4” to 1/2” thick around the drain.
  • Slope the mortar down to the drain to establish proper pitch.
  • Build up mortar layers until the required height is achieved.

Step 3: Screed and Level the Surface

  • Screed the mortar using a straight 2 x 4 to level and smooth the surface.
  • Slope should be 1/4” per foot minimum.
  • Allow the mortar to fully cure based on manufacturer recommendations.

The mortar base provides the pre-slope needed for efficient linear drain performance.

Install the Waterproofing Membrane

Before setting tile, a waterproofing membrane must be installed to prevent leaks. This provides a continuous water barrier that seals the entire shower floor and walls.

There are two main options – sheet membranes that adhere in a single piece or liquid membranes applied by brush or roller. Follow all instructions from the manufacturer. Here are the basic steps:

Sheet Membrane

  • Cut membrane pieces to fully cover the shower floor and 4-6” up walls.
  • Fold back half of each sheet and apply thinset to substrate with a 1/4” notch trowel.
  • Embed membrane into thinset and roll flat using a paint roller to maximize adhesion.
  • Overlap seams by 2-3” and seal with thinset and seam tape.
  • Apply thinset and membrane up shower walls and 2-3” into the horizontal plane.

Liquid Membrane

  • Prime all surfaces following product directions.
  • Apply membrane in two coats using a paintbrush or roller.
  • Fully saturate the floor and extend at least 6” up shower walls.
  • Extend 2-3” into corners where walls meet.
  • If reinforcing fabric is required, embed between coats.
  • Allow membrane to fully cure based on manufacturer specs.

The waterproofing seals and prepares for tile installation.

Set and Grout Shower Wall Tiles

With waterproofing complete, tile installation can begin. It is best to start with the shower walls. This allows the wall tile to overlap the floor membrane for proper sealing.

Follow standard practices for setting shower wall tiles:

  • Apply thinset mortar to the walls using a notched trowel.
  • Press tiles into the mortar and use spacers for even grout lines.
  • Cut edge tiles to fit using a wet saw or tile cutter.
  • Let thinset cure fully before grouting (24-48 hours).
  • Mix and apply grout, scrubbing into the grout lines.
  • Clean excess grout off the tile surface with a sponge.
  • Let grout cure 24 hours then buff off any remaining haze.

Check for complete coverage of the waterproofing by wall tiles. The floor tile will overlap the wall tile for ideal water protection.

Install the Shower Floor Tiles

Once the walls are fully tiled and grouted, move to tiling the shower floor. A smooth, level surface is essential for proper drainage. Follow standard practices:

  • Apply thinset to the shower pan using a notched trowel.
  • Lay the floor tiles in thinset, using spacers and working in sections.
  • Ensure tiles are level across the floor as work progresses.
  • Cut edge floor tiles to fit using a wet saw or tile cutter.
  • Allow thinset to cure fully before grouting the floor (24-48 hours).
  • Mix and apply grout, working it into floor grout lines.
  • Let grout cure then buff off remaining haze.

Take extra care when spreading thinset and fitting tiles around the linear drain. Any unevenness at the drain can impede proper drainage. The first floor tiles should overlap the waterproofing.

Finish Plumbing and Caulk Seams

The linear drain and tile installation are now complete. All that remains is finishing the plumbing connections and applying caulk.

  • Connect PVC piping from the drain body to existing plumbing lines.
  • Seal all seams around the drain body with silicone caulk.
  • Apply a silicone caulk bead along all wall/floor joints.
  • Caulk the joint between tile and other surfaces like the threshold.

Let caulk fully cure for 24-48 hours. Avoid running water into the drain for at least 72 hours while materials fully dry. The caulk seals the system and completes the linear drain installation.

Helpful Tips and Suggestions

Follow these additional pointers to ensure success throughout the installation process:

  • Always double check measurements before cutting tile or membranes.
  • Carefully follow all manufacturers’ installation instructions.
  • Wear safety goggles and gloves when handling mortar mixes or cutting materials.
  • Do not install tile over any sections where the membrane is compromised.
  • Apply multiple thin coats when using liquid membranes.
  • Periodically check thinset coverage under tile as you work.
  • Remove all tile spacers before grouting floor or walls.
  • Wait the recommended time before grouting or using shower.
  • Research local plumbing codes for requirements on drain connections.
  • Hire a professional if you are uncomfortable performing any part of the installation.

Proper planning, patience, and care at each step will result in a successful linear drain installation that provides exceptional performance and lasting quality.

Frequently Asked Questions about Installing a Linear Shower Drain

Here are some common questions homeowners have about installing a new linear shower drain:

What size linear drain do I need?

The drain size should match the width of your planned shower. Standard options include 30”, 36”, 48”, 60”, 72” and custom lengths. Measure the shower width and buy the same length drain channel or just longer.

How difficult is it to install this drain?

The installation process is straightforward but does require some plumbing and tiling work. Handy homeowners can usually install a linear drain successfully over a weekend. Hire a contractor if you lack the skills or confidence.

Does the drain location matter?

Install the drain several inches from the shower entry threshold. Centering it under the showerhead is ideal. The drain pipe also needs to tie into existing plumbing.

What slope should the shower floor have?

The floor needs a minimum slope of 1/4-inch per foot running towards the drain. A mortar bed creates this slope and ensures proper drainage.

Can I use regular drywall in the shower?

No. A waterproof backer board or cement board is required underneath shower tiles to prevent moisture damage. Apply a waterproofing membrane over the entire surface before tiling.

How do I connect the drain to plumbing?

Use PVC pipe and fittings to transition from the drain body to existing drain lines. The assembly must be leak-free. Consult a plumber if you are unsure.

Does linear drain size affect performance?

Longer drain channels allow more water intake at a lower flow rate. However, proper slope is the most important factor for good drainage. A 4-inch channel can often perform just as well as larger sizes.

How much does a new linear drain cost?

Pricing ranges from $200 to $800 depending on size, design and material. The total project cost also includes all mortar, tiles, fittings and other installation supplies.

What are the best waterproofing options?

Both sheet membranes and liquid membranes properly waterproof when installed correctly. Liquid roll-on membranes are often easier for novice installers.

We hope these answers help provide insight on installing linear shower drains! Let us know if you have any other questions.


Installing a streamlined linear drain system can take your shower to the next design level while improving overall drainage. Carefully plan the layout and positioning, assemble quality components, slope the floor properly, and seal all surfaces to achieve lasting quality and performance. With attention to detail throughout the process, even first-time DIYers can successfully tackle a linear drain installation project over a weekend. This modern drain style will provide an elegant focal point and promote improved hygiene for years to come.

How to Install a Linear Shower Drain