Whether it’s a renovation or new construction, linear shower drains are placed in almost every modern bathroom. 

Changing the typical center floor drain with a linear shower drain is a terrific way to boost the aesthetic appeal of your new shower while also improving its utility. Continue reading to learn how to install a linear shower drain if you have the abilities, expertise, and time to complete this DIY project.

Table of Contents:

What Are Linear Drains?

Whereas a center drain has a small square or circular drain hole, a linear drain consists of a lengthy drain trough that often runs parallel to the shower’s opening along the back wall. The trough empties into an unseen central drain attached to the drainpipe for the shower.

Linear drains can have metal covers, similar to standard center drains, but they can also have covers that match the color and appearance of the surrounding tile, allowing the drain to blend in with the aesthetic rather than standing out.

Prior to Starting

The installation of the floor, linear drain system, and tiles will take several days, even if you work rapidly, because the mortar requires time to dry; thus, the bathroom should not be utilized during this time. If you do not have a second bathroom with a shower, it is recommended that you locate a different place to stay for a few days or plan a spot, such as a friend’s house, where you may shower when necessary.

Moreover, before beginning, you should properly clean the area. This prevents dirt and dust from interfering with the adherence of the mortar, grout, and silicone utilized in the procedure. Most municipalities do not require a permission for installing a new shower; however, if you are replacing the drain lines, you may need one. Check your local building codes and, if necessary, acquire permits.

Measure and Mark the Location of the Drain

The first step is to use a measuring tape to determine the location of the drain and to mark the desired installation location. Generally, linear shower drains are built in four distinct methods, including one-sided wall-mounted, three-sided wall-mounted, free floor-mounted, and shower entrance floor-mounted.

The most prevalent solution is one-sided wall-mounting. It refers to the drain that runs along the rear wall of the shower on one side. The ends of the shower drain do not reach all the way to the side walls.

Three-sided wall-mounted drains are identical to one-sided wall-mounted drains, with the exception that the ends of the drain extend to the side walls of the shower, making contact on three sides as opposed to one.

Tip: To ensure proper drainage, the shower floor must slope toward a linear drain; therefore, the linear drain must be installed parallel to the shower’s entry. Otherwise, the slope will produce a lip at the entry, which might pose a tripping hazard.

Determine the Drain Depth and Drill a Drain Hole

One of the objectives during the construction of a linear drain is to ensure that the grate cover is absolutely flush with the surrounding tile. To reach this objective, you must calculate and measure the drain height so that the top of the drain sits 1/16 inch below the neighboring tile before the grate cover is installed.

It is advisable to measure the height of the linear drain assembly with and without the grate cover so that, if the difference is higher than or less than 1/16 inch, you can adjust the height during installation so that the floor is level with the drain.

If you need to relocate the drain line, use a drill with a hole saw bit to create precise circular cuts in the plywood. It is advisable to drill a 3 1/2-inch hole and locate the middle of the drain approximately 2 1/2 to 3 inches from the back wall.

To obtain a precise height measurement, slide the base drain into the drain line and insert the linear drain. Mark the desired height on the shower wall, and then remove the linear and base drains.

Install Bituminous Paper and Wire Lath

Use a utility knife to cut tar paper in order to cover the plywood subfloor with it. Ensure that it covers the edges and base of the shower walls as well. This layer of asphalt paper prevents the plywood floor from absorbing any moisture from the shower pan mortar mixture.

With a pair of wire cutters, you may also cut a piece of wire lath to place on top of the tar paper and aid in stabilizing the mortar mixture for the shower pan.

Connect Then Install the Base Drain

Cut the wire lath and tar paper so that the base drain may be put into the drilled hole and attached to the drain line before pouring the mortar mixture for the shower pan. Ensure that the drain is appropriately aligned and level for the intended installation site.

Pour water down the base drain to ensure there are no leaks between the base drain and the drain line. If the fit is tight enough, you shouldn’t require drain glue, but if you’re concerned about the connection, use drain glue to seal the pieces.

Make the Floor Slope

This procedure begins with the mortar mix in the pre-pan. Mix the mortar with a bucket and a shovel, or try using a mixing paddle to make the job easier. Put mortar over the tar paper and wire lath, but avoid covering the foundation drain.

For the water to effectively drain from the shower, it is necessary to establish a floor with a slope of 1 to 2 degrees, or approximately 14-inch per foot, toward the drain. Ensure that the gradient is right by using a bubble level.

Once the pre-pan mortar is level and flat, allow it to set for approximately 24 hours.

Attach Waterproof Lining and Clamp Ring

The next step is to cut and install a waterproof liner on top of the pre-pan mortar, as waterproof shower liners give a major degree of protection against water damage, rot, and invisible mold growth. The liner must extend a minimum of 6 inches up the sides of the shower wall to form an effective water barrier.

You can use nails or screws to secure the liner’s edges to the walls to prevent it from slipping out of place. Cut a small slit in the liner over the bolts on the base drain, then slide the liner over the bolts to secure it. Cut a hole in the liner the same size as the opening of the base drain, then attach the clamping ring to the base drain to secure the liner and form a watertight seal.

Add Mortar and Tiles to the Top-Pan

If you hid your first height marker, it is now time to remeasure and remark the height. Using a bucket and a shovel, combine the mortar mixture for the top-pan, then connect the linear drain to the drain base and verify that the drain is level. Typically, linear drains are equipped with adjustable feet that may be pushed under the drain’s edges to ensure that the drain is level.

Pour the top-pan mortar onto the waterproof liner and fill the liner while leveling the mortar to maintain a gradient of approximately 1 to 2 degrees or a slope of approximately 14-inch per foot toward the drain. Provide adequate space for the last coat of thinset and tile installation.

Complete the installation of the shower tiles and ensure that the linear drain is positioned 1/16 inch below the top of the neighboring tiles.

Tip: Cover the perimeter of the drain base with a bead of silicone caulk and use pea gravel to cover the drain flange weep holes to prevent mortar from clogging these holes.

Close the Drain and Cover the Grate

Upon completion of the installation of the shower, the final step is to apply a bead of silicone caulk to the junction between the tiled floor and the drain, followed by the linear drain floor grate cover. After proper installation of the grate cover, the 1/16-inch height differential should be eliminated, leaving you with a shower floor that is perfectly level.

FAQs in Relation to Linear Shower Drains

Is it worthwhile to invest in linear shower drains?

Linear drains are an excellent choice for small showers because they drain water more efficiently. They also have a more modern appearance and may be easier to clean than traditional drains

Do linear drains clog more easily?

Linear drains have a sloped surface that allows water to flow smoothly and eliminates the possibility of clogs. They're also less difficult to install than traditional drains, with most requiring only a few screws or bolts to secure them in place.

Should a linear drain be installed from wall to wall?

The best linear drain installation is against the wall and wall-to-wall. This type of installation is strongly recommended not only to improve the function of the shower but also to protect the integrity of the rest of the bathroom.

Is it true that linear shower drains are more expensive?

A linear shower drain unit will typically cost significantly more than a circular or square shower drain. You should also budget for additional labor and installation. Installing a linear shower drain will necessitate more collaboration among your plumber, contractor, and tile installer.


Installing a linear drain requires more than just the drain itself. Also, you may need to be able to lay mortar at a particular angle, run and connect drain lines, cut and install tile, and seal the entire shower to prevent water damage, rot, and mold growth. Despite the fact that a skilled, experienced do-it-yourselfer is capable of doing this task, you may lack the necessary skills or lack the time to do so. Consider hiring a professional to guarantee that this job is completed correctly the first time, so that there are no issues in the future and you are satisfied with the outcome.

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