Shower System Installation Handbook

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-21
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.
Ensure a suitable structure and substrate for the shower floor. This may
require the services of a qualified design professional (e.g., architect,
engineer, etc.).
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
backerboard, fiber-reinforced water-resistant gypsum backerboard, coated
glass mat water-resistant gypsum backerboard, Portland cement mortar,
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 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.
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.
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/-R and KERDI-BOARD-SC/-SB.
Solid Backing Materials
Gypsum wallboard – ASTM C1396/C1396M
Cementitious backer unit – ANSI A118.9 or ASTM C1325
Fiber-cement backerboard – ASTM C1288
Fiber-reinforced water-resistant gypsum
backerboard – 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.