Shower curbs may be constructed of wood framing and sheathing or masonry and
subsequently waterproofed using the Schluter-KERDI membrane. This can be very time consuming work.
Schluter-Systems offers quick and easy to install alternatives to shower curbs
constructed of traditional building materials. Schluter-KERDI-BOARD-SC is a prefabricated
shower curb constructed of the Schluter®-KERDI-BOARD waterproof
building panel that is specifically designed to integrate with the Schluter-Shower System.
The shower curb is waterproof, lightweight, stable, load bearing and easy to install.
In this video, installation of the KERDI-BOARD-SC in a two-wall shower is demonstrated.
Place the KERDI-BOARD-SC shower curbs around the shower base.
Mark the curb to be cut using a straight edge. The curb may be cut
using a utility knife or a handsaw. Check the curbs for proper fit.
The shower curbs are installed using unmodified thin-set mortar.
A 1/4 inch x 3/8 inch square or U-notched trowel is used to apply the mortar.
Apply a thin layer of mortar to the subfloor, wall, and edge of the shower tray 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. Press the curb firmly into place, making sure
the cut end is placed against the wall. Repeat the process for the adjacent curb.
Verify that the curbs are level. To complete the integration of the KERDI-BOARD-SC,
Schluter-KERDI-BAND waterproofing strips and Schluter-KERDI-KERECK pre-formed corners are
used to seal the curbs to each other, the shower base, and the walls. The shower base has already
been waterproofed using the KERDI membrane. The KERDI waterproofing accessories are
installed using 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. The order in which the waterproofing
accessories are installed may vary, provided that a minimum two inch overlap is achieved at
all seams and cut ends of the KERDI-BOARD-SC. In this application, we begin by applying
KERDI-BAND to the outside corner of the curb. Measure and cut the KERDI-BAND to a length
equal to the height of the curb. KERDI-BAND may be creased prior to
installation to help maintain tight corners and make subsequent tile setting as easy as possible.
Apply unmodified thin-set mortar to the outside corner.
Embed the KERDI-BAND into the thin-set mortar using the flat side of the trowel
or a dry wall finishing knife. Our next step is to seal the
inside corner where the two curbs meet. Measure and cut a section of KERDI-BAND
to cover this inside corner from the surface of the shower base to the top of the curbs.
Apply unmodified thin-set mortar to the inside corner.
Solidly embed the KERDI-BAND into the thin-set mortar.
The next step is to install a KERDI-KERECK preformed outside corner at the top of the
inside corner where the two curbs meet. Apply unmodified thin-set mortar to the area
where the KERDI-KERECK corner is 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. KERDI-BAND is used to seal the seam between
the adjacent curbs. Measure and cut the banding to cover the seam on the
outside and top of the curbs. Apply unmodified thin-set mortar
to the junction between the two curbs. Embed the KERDI-BAND into the thin-set mortar
Next, we will install a KERDI-KERECK preformed inside corner at the outside
corner on top of the curb. Apply unmodified thin-set
mortar and solidly embed the corner. Finally, we will seal the curbs to the
shower base, beginning with installation of KERDI-KERECK inside corners using the same
method demonstrated previously. Use KERDI-BAND to complete the
seal between the curbs and shower base. Note that a two 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 to seal all remaining joints, ensuring that the minimum two
inch overlap is achieved at all transitions. The Schluter-KERDI-BOARD-SC prefabricated shower
curb offers a quick and easy alternative to curbs constructed of other building materials.