Schluter-KERDI-LINE is a low profile linear floor drain specifically designed for bonded
waterproofing assemblies. The floor can be sloped on a single plane to KERDI-LINE,
which enables the use of large-format tiles and creates interesting design opportunities.
There are a variety of different grate designs available for KERDI-LINE,
including a tile grate option, all giving endless opportunities to create stunning designs!
The KERDI-LINE channel body and grate are sold separately.
In the channel body box you will receive: A channel support that is customizable to a wall
or intermediate installation, a no-hub coupling required for plumbing connections and a channel
body with an integrated KERDI collar, And waterproofing accessories including:
Schluter®-KERDI-KERECK inside and outside corners.
And finally, a Schluter®-KERDI-SEAL-PS pipe seal and KERDI-SEAL-MV mixing valve seal.
Depending on your grate design choice, you will receive:
A grate
And a grate frame with height adjustment spacers.
Specifically designed for use with the KERDI-LINE drain are the Schluter-KERDI-SHOWER-LT and
Schluter-KERDI-SHOWER-LTS are sloped shower trays. The trays are made of lightweight,
expanded polystyrene with integrated Schluter-KERDI waterproofing.
They are available in several different sizes and for both wall and center drain placement.
The substrate is clean, even and load-bearing.
Any leveling of the floor must be done prior to the installation of the KERDI-LINE channel body.
Let’s start the installation. First, dry-fit the components.
Lay the channel support on to the back of the shower tray. Mark where the flat end of the tray
needs to be cut away. The tray also features a guide that matches KERDI-LINE lengths.
Cut the flat end of the KERDI-SHOWER-LTS shower tray to fit around the channel support.
Dry fit the tray, channel support, and channel body to verify proper positioning and fit.
This demonstration assumes that there is access to the plumbing from below
and the waste line can be connected after installing KERDI-LINE.
When there is no access to the plumbing from below, install and connect the Schluter-KERDI-LINE
to the waste line simultaneously. Please refer to the “No Access Plumbing Demonstration with
KERDI-LINE” video for this method and return to this video when that work is complete.
Make sure the substrate is clean and free of debris.
Apply any of our Schluter® thin-set mortars, OR an unmodified thin-set
mortar to the substrate with a notched trowel where the drain is to be placed.
A 1/4 inch x 3/8 inch square or U-notched trowel is used to apply the mortar.
Solidly embed the channel support into the mortar.
Next, we’ll install the shower tray. Using the same notched trowel,
apply a thin layer of mortar to the substrate with the flat side of the trowel to produce solid
contact with the surface and then comb additional mortar using the notched side of the trowel.
Install the tray flush with the surface of the channel support.
Place a cut section of cardboard over the tray to protect the KERDI
and solidly embed the tray into the mortar.
Apply thin-set mortar to the top of the channel support…
…and press the channel body firmly into the mortar,
ensuring full support of the bonding flange.
Check to make sure KERDI-LINE is level. Next we’ll begin the
waterproofing connections. Remove the tape from the KERDI collar.
The KERDI collar needs to be trimmed where the KERDI-LINE is adjacent to the walls.
Mark the KERDI collar where necessary and cut.
The KERDI collar on KERDI-LINE is integrated with the adjoining waterproofing assembly
using any of our Schluter® thin-set mortars, or an unmodified thin-set mortar.
The mortar is mixed to a fairly fluid consistency, but still able to hold a notch.
A 1/4 inch x 3/16 inch V-notched trowel or the Schluter-KERDI-TROWEL, which features
a 1/8 inch x 1/8 inch square-notched design, is used to apply the mortar.
Apply a thin layer of the mortar with the flat side of the trowel to produce solid
contact with the surface and then comb additional mortar using the notched side of the trowel.
Embed the KERDI collar into the thin-set mortar using the flat side of the trowel
or a dry wall finishing knife to ensure full coverage and remove air pockets.
The next step is to install the KERDI-KERECK inside corners.
The inside corners must be cut at the KERDI-LINE to avoid overlap into the channel.
Apply thin-set mortar to the area where the KERDI-KERECK inside corners are to be installed.
Embed the KERDI-KERECK into the thin-set mortar using the flat side of the trowel
or a dry wall finishing knife. Holding one side of the corner in
place while embedding the other side in the mortar helps keep corner installation simple and easy.
Repeat the process at the remaining inside corner.
Continue installation of the various accessories to complete the waterproofing application.
Measure and cut sections of KERDI-BAND such that a 2 inch overlap is achieved at all junctions.
KERDI-BAND may be creased prior to installation to help maintain
tight corners and make subsequent tile setting as easy as possible.
Apply thin-set mortar to the area where the KERDI-BAND is to be installed.
Embed the KERDI-BAND into the thin-set mortar using the flat side of the trowel
or a dry wall finishing knife. Note that a 2 inch overlap can be achieved
at KERDI-KERECK without continuing KERDI-BAND all the way to the corner of the shower.
This will limit build-up of the membrane in these areas and make setting small tiles easier.
Repeat this process at all remaining joints ensuring
that the minimum 2 inch overlap is achieved at all transitions.
The order of Schluter-KERDI waterproofing installation may vary from that demonstrated,
as long as all surfaces are covered and 2 inch overlaps are maintained at all seams.
A water test is recommended before setting tile to verify a successful waterproofing installation.
This evaluation may be required by building code officials on some projects.
Wait 24 hours after the membrane installation is complete to allow for final set of the mortar and
to ensure waterproof performance of the assembly at seams and connections before water testing.
Please refer to the How to Perform a Water Test video for this method and return to
this video when that work is complete. If tile is to be set on floors adjacent to
the shower, consider the use of the Schluter-DITRA uncoupling and waterproofing membrane, which can
be sealed to the Schluter-Shower System to provide comprehensive waterproofing in the bathroom.
More information is available in the “DITRA Connection to Shower Base Video”.
There are a variety of different grate options available for KERDI-LINE,
including a tileable option. The installation process is the same
for the various grates, with the exception of the KERDI-LINE Tile Grate Option.
If the Tile Grate option is used, please refer to the “KERDI-LINE Tile Grate Installation” video.
Once the waterproofing is complete, the grate assembly and tile can be installed.
Remove the tape from the channel body.
The grate frame is set in conjunction with the surrounding tiles.
Apply any of our Schluter® thin-set mortars, OR an unmodified thin-set mortar to the
underside of the grate frame along the back and sides and place it into the channel body,
ensuring full coverage and support. Insert the foam spacer into the grate
frame to reinforce it during the remainder of the tile installation.
Insert the height adjustment spacers on to the tabs along the inside of the grate frame.
Dry fit the tile and turn the bolts to adjust the frame to sit slightly proud of the tile,
taking in to account the thin-set mortar that will be used to install the tiles.
Fill the front side of the grate frame with thin-set mortar.
Full coverage of thin-set mortar under the grate frame is essential.
Immediately clean away any excess setting material from the surface of the grate frame.
Install the tile up to the grate frame, making sure to use an appropriate sized
notch trowel for the tile. Back butter the tile as needed to achieve full coverage.
Make any final adjustments to ensure the grate frame is even with the surrounding tiles.
It’s important to do this while the thin-set is still workable to ensure a flush transition.
Install the remaining tiles on the shower base and curb. Finally the grate is set in
to the frame to complete the installation. With their high-design appeal, linear drains
make a statement in the shower. With KERDI-LINE drains and the variety of grates available,
your shower will be stunning and completely waterproof underneath!
If you still have questions, please contact our Customer Support Specialists. For more information
on Schluter products, visit schluter.com or check out our YouTube channel to view our videos!