How to Install A Schluter-KERDI-SHOWER Tray

December 18, 2018


An ideal system for constructing a shower base that's designed to integrate with the Schluter Shower System

Transcript of shower tray video:

KERDI-SHOWER pre-fabricated trays are ideal for constructing a shower base and designed to integrate with the Schluter Shower System. They are lightweight and easy to install. They can also be cut to size and extended with dry pack mortar if required.

KERDI-SHOWER trays are available in an expanded range of sizes and configurations.

Some of these sizes feature reduced thickness to help facilitate curbless shower applications. Many of our trays are also available with integrated waterproofing, making shower installation even easier.

Let’s take a look at the installation of one of our KERDI-SHOWER-TT thin trays.

Cut a hole in the substrate for the Schluter-KERDI-DRAIN and coupling to the waste line using the template provided.

Do not use the opening in the shower tray as a guide. You must limit the diameter of the hole to five inches maximum to ensure proper support for the tile assembly.

If there is access to the plumbing from below and the waste line can be connected to the KERDI-DRAIN after installation, you can install the tray prior to the drain.

When there is no access to the plumbing from below, you will need to install and connect the KERDI-DRAIN to the waste line before installing the shower tray. Please refer to the No Access Plumbing Demonstration with KERDI-DRAIN & KERDI-SHOWER Trays Video.

The substrate must be clean, even, load-bearing and level. Any leveling of the floor must be done prior to installing the tray.


Apply thinset mortar

The KERDI-SHOWER-TT is installed using any of our Schluter thin-set mortars or an unmodified thin-set mortar.

A one-quarter inch by three-eighths inch square or U-notched trowel is used to apply the mortar. Apply a thin layer of mortar to the subfloor with the flat side of the trowel and then comb additional mortar using the notched side of the trowel.


Install the shower tray

Place the shower tray and solidly embed in the mortar. If you are not immediately installing the KERDI-DRAIN, clean the mortar from the step in the shower tray and the area surrounding the hole in the subfloor. Otherwise, the dried mortar might interfere with your drain installation.

A curbless application can be achieved by installing a plywood or OSB underlayment and DITRA-HEAT or DITRA-XL membranes over the bathroom floor.

Since we are raising the floor, the transition to the adjacent room must be checked.  The transition will typically be manageable when the adjacent floor covering is relatively thick, such as a carpet with pad or three-quarter inch thick hardwood.


Add a shower curb

The tray can also be installed in conjunction with our pre-fabricated shower curbs. 

The KERDI-BOARD-SC shower curb is installed as per usual, using any of our Schluter thin-set mortars or an unmodified thin-set mortar.

Make sure the mortar is applied to all points of contact with the curb, including the subfloor, walls and the edge of the shower tray for proper support. Embed the curb and make sure it is level.


Install the KERDI-DRAIN

Next, we will install the KERDI-DRAIN. Fill the step in the shower tray and the area surrounding the hole in the subfloor completely with thin-set mortar. 

Press the KERDI-DRAIN firmly into the mortar for full support of the bonding flange.

Clean excess mortar from the bonding flange to prepare for the KERDI collar installation.

Use a Schluter®-KERDI-TROWEL or a  1/4" x 3/16" (6 mm x 5 mm) V-notched trowel for the KERDI-installation.

Using the flat side of the trowel apply thin-set mortar over the bonding flange and within the recessed area of the shower tray surrounding the drain. Then, comb additional mortar using the notched side of the trowel.

Center the included KERDI collar, over the KERDI-DRAIN and embed using the flat side of the trowel or a drywall taping knife. Make sure this connection is secure.

Using the same technique, install the KERDI-KERECK corners and KERDI-BAND waterproofing strips to seal the shower tray to the walls and curb.

Depending on project requirements and installer preferences, the order of installation may vary. Two-inch overlaps must be maintained at all seams. The system is designed to be flexible and meet the needs of the installer.

The installation of the KERDI-SHOWER-TT thin tray, KERDI-DRAIN and waterproofing is now complete.

Schluter shower trays reduce installation time and make shower installation easier than ever.


—This video comes from Schluter, one of ProTradeCraft's advertisers. See all of Schluter's content.