Installation Guide

Schluter
®
-KERDI waterproofing membrane or
Schluter
®
-KERDI-BOARD waterproof building panel
STEAM SHOWER ASSEMBLY — Schluter
®
-KERDI waterproofing membrane 17
Intermittent Use Steam Showers – Ceramic or stone tile
K-SSH-20
Areas of Application
Interior intermittent use steam showers (e.g., residential applications).
Over wood or concrete subfloors. See the Base information under
Requirements (below) for details.
Areas requiring disabled access/curbless applications; see detail K-SHBF
on page 12.
Limitations
Not intended for continuous use steam rooms (e.g., applications in spas,
fitness centers, etc.); see detail K-SR on page 18.
Certain glass tiles may not be compatible with bonded waterproof
membranes and/or may require special setting materials. Consult glass
tile manufacturer and Schluter
®
-Systems for more information.
Certain moisture sensitive stones, e.g., green marble, or resin-backed
tiles may not be appropriate for use in wet areas such as steam showers
or may require special setting materials. Consult stone supplier and
Schluter
®
-Systems for more information.
Do not use sawn lumber curbs on concrete subfloors subject to moisture
migration.
Requirements
Plywood, OSB, or concrete subfloor must be clean, even, and load bearing.
Provide insulation in wall and ceiling cavities to reduce moisture
condensation on the tiled surface.
Base – KERDI-SHOWER-T/-TS/-TT/-LT/-LTS or Portland cement mortar
bed
Curb – KERDI-BOARD-SC, KERDI-BOARD, concrete, masonry block, or
sawn lumber sheathed with solid backing (see below).
Bench – KERDI-BOARD-SB, KERDI-BOARD, concrete, masonry block,
or sawn lumber sheathed with solid backing (see below).
Solid backing – gypsum wallboard, cementitious backer unit, fiber-
cement underlayment, fiber-reinforced water-resistant gypsum
backerboard/underlayment, coated glass mat water-resistant gypsum
backerboard, Portland cement mortar bed, concrete, or masonry.
KERDI-DRAIN/-LINE shall be properly supported.
KERDI-DRAIN/-LINE shall be connected to the waste line; use ABS
cement for ABS drains, PVC cement for PVC drains, a no-hub coupling
for stainless steel drains with no-hub outlets, and thread sealing
compound or tape for stainless steel drains with threaded outlets.
Slope ceilings 2" (50 mm) per foot minimum to avoid condensation from
dripping onto occupants (may be sloped to center to minimize rundown
on walls).
Install KERDI waterproofing membrane on base and curb and
KERDI-BOARD waterproof building panel or KERDI waterproofing
membrane on walls and ceiling. For enclosed areas, also install on door
jambs, door header and past the door frame gasket, as applicable.
Minimum KERDI-BOARD thickness – 1/2" (12.5 mm) for studs spaced at
16" (40.6 cm) o.c. and 3/4" (19 mm) for studs spaced at 24" (61.0 cm) o.c.
KERDI-BOARD shall be fastened to wood or metal framing with
appropriate screws (i.e., coarse thread wood screw for wood studs and
self-tapping for metal studs) and corresponding KERDI-BOARD-ZT
washers. Screws must reach a depth of at least 3/4" (20 mm) in wood
studs and 3/8" (10 mm) in metal studs. Maximum allowable on-center
fastener spacing is 12" (30 cm) for walls and 6" (15 cm) for ceilings.
It is the specifier's responsibility to treat and address all penetrations
through the KERDI membrane or KERDI-BOARD (e.g., showerhead,
mixing valve, steam inlet, lights, etc.) in the installation. All penetrations
must be treated with KERDI-SEAL-PS/-MV seals, room temperature
vulcanizing sealant or other suitable sealant with a working temperature
over 250 - 300 °F (120 - 150 °C).
When using the stainless steel KERDI-DRAIN bonding flange, use
KERDI-FIX to bond KERDI to the integrated bonding flange.
Movement joints shall be provided at all changes in plane, including floor/
wall, wall/wall, and wall/ceiling transitions. Schluter
®
-Systems
prefabricated movement joint profiles (e.g., DILEX-EKE) provide a
maintenance-free alternative to sealant; see page 40.
All horizontal surfaces (e.g., benches, curbs, window sills, shelves, etc.)
must be sloped toward the shower drain. This can be done by sloping
the substrate or the tile.
Substrate Preparation
Verify that subfloor panels are properly fastened to framing members.
Any leveling of the subfloor must be done prior to installing
KERDI-SHOWER-T/-TS/-TT/-LT/-LTS/-SR and KERDI-BOARD-SC/-SB.
Solid Backing Materials
Gypsum wallboard – ASTM C1396/C1396M
Cementitious backer unit – ANSI A118.9 or ASTM C1325
Fiber-cement underlayment – ASTM C1288
Fiber-reinforced water-resistant gypsum
backerboard/underlayment – ASTM C1278
Coated glass mat water-resistant gypsum backerboard – ASTM C1178
Portland cement mortar – ANSI A108.1B
Concrete
Masonry
Setting and Grouting Materials
Unmodified thin-set mortar – ANSI A118.1
Grout – ANSI A118.3, A118.6, A118.7
Installation Specifications
Solid backing panels – follow manufacturer’s directions
Portland cement mortar bed – ANSI A108.1B
Tile – ANSI A108.5
Grout – ANSI A108.6, A108.10
Other Considerations
When KERDI-SHOWER-T/-TS/-TT/-LT/-LTS tray dimensions do not
match the dimensions of the shower compartment, the tray may be cut
or extended with dry pack mortar.
Shower grab bars must be anchored in the structure or solid blocking
behind KERDI-BOARD.
When KERDI and tile are installed on the ceiling, the solid backing and
fasteners must be able to support the load of the tile and setting and
grouting materials. When KERDI-BOARD and tile are installed on the
ceiling, the fasteners must be able to support the load of the tile and
setting and grouting materials.
A water test is strongly recommended before setting tile to verify a
successful installation. Wait 24 hours minimum after the membrane
installation is complete to allow for final set of thin-set mortar and ensure
waterproof performance at seams and connections. Refer to local
plumbing codes for any specific requirements in your area.
Schluter
®
-Systems profiles may be used to finish and protect outside
corners and eliminate the use of sealant at inside corners; see page 40.
Schluter
®
-SHOWERPROFILE-S/-R profiles eliminate the need for cutting
wedges of tile by covering the exposed wall area where the floor slopes
to KERDI-LINE.]
Schluter
®
-SHELF-E/-W/-N are alternatives to tiled shelves that can be easily
installed on walls and in corners and niches; see page 40.
Where a waterproof floor adjacent to the shower is desired, DITRA or
DITRA-HEAT uncoupling membranes shall be installed. Floor/wall
connections shall be sealed with KERDI-BAND.