Floors, Interior - Tile over Existing Vinyl Floors

• for wood substrates, subfloor/underlayment configuration according to details for
  
       16" (406 mm) o.c. joist spacing 19.2" (488 mm) o.c. joist spacing 24" (610 mm) o.c. joist spacing Natural Stone 

Substrate Preparation

• ensure that the structure beneath the vinyl is sound and adequate
• ensure that vinyl is well adhered
• remove any wax and clean vinyl
• nail off floor with ring shank flooring nails every 4" (102 mm) o.c. – nail length equal to thickness of flooring “sandwich”

Movement Joints

• Schluter-DITRA does not eliminate the need for movement joints, including perimeter joints, within the tiled surface. Movement joints should be installed in accordance with industry standards and norms; see guidelines for the placement of movement joints for more details

Setting and Grouting Materials

• fast-setting latex portland cement (p.c.) mortar - ANSI A118.4
• unmodified thin-set mortar - ANSI A118.1
• grout - ANSI A118.3, A118.6, A118.7, A118.8

Setting and Grouting Specifications

• tile - ANSI A108.5
• grout - ANSI A108.6, A108.9, A108.10

Other Considerations

• Schluter-DITRA should be adhered to the vinyl flooring using a fast-setting latex-portland cement mortar suitable for bonding to vinyl. As an alternative, a suitable cement-based embossing leveler or an appropriate latex-modified thin-set mortar can be used to skim coat the vinyl to provide a bonding surface. When skim coat is cured, DITRA can be adhered to the skim coat using an unmodified thin-set mortar. See thin-set facts for discussion on latex-modified thin-set mortars sandwiched between two impervious layers
• seaming Schluter-DITRA, including floor/wall connections, with Schluter-KERDI-BAND may be appropriate in cases where a break in the water line of an ice maker or dishwasher can damage pre-existing moisture-sensitive substrates and underlayments. KERDI-BAND floor/wall connections are just as easily concealed with wood base as with tile. KERDI-BAND floor/wall connections in dishwasher alcoves are parged with thin-set; see waterproofing requirements for more details
• vapor barrier on crawl space floors according to regional building codes
• certain moisture-sensitive stones, e.g., green marble, or resin-backed tiles may require special setting materials. Consult stone supplier and Schluter-Systems for more information