SGM Crack Suppression Membrane System (CSM 40) is a self-adhering crack isolation membrane. Crack Suppression Membrane System (CSM 40) consists of a base layer of polymer modified elastomers permanently laminated to a unique??stress flex??fiber sheet to form a single, high performance, self-bonding membrane.

INSTALLATION

SUITABLE SUBSTRATES

Poured concrete, pre-stressed and precast concrete. Concrete backer-board, mud beds, gypsum, lightweight concrete, and patching compounds.

• Wood:?Exterior or Exposure 1 plywood, APA-rated sheathing, sturdy-I-floor, hardwood, tongue and groove, and oriented strand board (OSB) standard face. (Gap between sheeting as required). Other substrates include ceramic and porcelain tile, stone, VCT/ VAT, metal, radiant-heated, painted and sealed floors, and floors damaged by dry shrinkage and structural movement.

SURFACE PREPARATION

Surfaces must be level, structurally sound and meet 1/360 for ceramic and porcelain tile or 1/720 for stone tile on live or dead loads. Grind bumps and level slab depressions with quality latex underlayment in accordance with manufacturer?s instructions. Surfaces must be free of holes, projections, moisture, or bond breakers. Scarify smooth surfaces. Maximum variation of ? inch in ten (10) feet from the required plane. Refer to?Crack Suppression Membrane System (CSM 40) Information Sheet?for suitable substrates. Ensure joist spacing consists of no more than sixteen (16) inches on center and a double subfloor consists of at least ? inch per sheet. Perform?Black Mat MVT (Moisture Vapor Transmission)?test. If MVT is present, conduct?F-1869-98?test for emissions. Contact SGM, Inc. for instructions if MVT drive is in excess of?10#/1000SF/24HRS. Apply cementitious parge coat to concrete block and allow to cure before installation apply?Southcrete? 25 Acrylic Mortar Admix?to highly porous surfaces such as mud beds, gypsum/gypcrete, lightweight concrete, and patching/leveling compounds. Allow?Southcrete? 25 Acrylic Mortar Admix?to cure 24 hours prior to applying primer. Some backer boards are not suitable for vertical?Crack Suppression Membrane System (CSM 40)?in application. A successful overnight pull test is required. All installations begin with a clean, dry floor. Substrates must be well adhered to and clean of wax, petroleum sealers, dirt, grease, oil, or other bond-breakers. Recommended for installations under thin-bed and medium-bed mortar installations (ANSI 118.4) of ceramic, porcelain, stone, slate, marble, and granite tiles. Also for use under brick, pavers, hardwood, and manufactured wood. Also ideal for use with radiant heated floors and low voltage tile warming systems.

APPLICATION

Measure and pre-cut membrane to four (4) inches to six (6) inches longer than required size. Re-roll membrane to half the room?s depth. Apply Interior or Exterior Primer as required.

• Interior Primer:?Should be applied with a short nap roller, flat trowel, brush applicator, or sprayer. Substrate temperature should be at least 65?F (sixty-five degrees Fahrenheit).
• Exterior Primer:?Should be applied a short nap roller, notched trowel (no larger than 1/16? x 1/32? x 1/32?) or paintbrush. Substrate temperature should be at least 55?F (fifty-five degrees Fahrenheit). Shake, mix or stir primer thoroughly. Prime only an area that will covered by membrane within four (4) hours. Apply a thin film of uniform thickness to substrate in single strokes. Do not re-roll primer. Air pockets may form if membrane is installed over wet primer. Allow primer to dry until tacky to touch, but nontransferable to finger. This may take as little as ten (10) minutes, but usually no more than forty-five (45) minutes, depending upon temperature, humidity, internal moisture level/porosity of substrate, and application thickness. See primer labels for additional information. Slit release paper and allow membrane to roll out, adhesive-side down, across primed floor. Press membrane into place with flat side of trowel applying fifty (50) pounds of pressure per square inch or a?75-100# Roller.
• Full Floor Coverage Application:?Butt joint thirty-six (36) inch?Crack Suppression Membrane System (CSM 40)?or overlap and single cut through to remove excess. For end seams, continue with next roll and butt joint ends. Membrane is non-directional. Placement of control joints may be ignored. Isolation joints, such as around weight bearing columns, and expansion joints placed for vertical movement need to be carried through to tile installation. Soft joints in tile patterns are required as per the?Tile Council of North America (TCNA) Handbook 2019.
• Strip Applications
  • Joint Relocation:?Thirty-six (36) inch?Crack Suppression Membrane System (CSM 40)?may be placed over control/sawcut joints. Offset?Crack Suppression Membrane System (CSM 40)?two (2) feet to one side of joint. On one (1) foot side of?Crack Suppression Membrane System (CSM 40), cut through membrane at tile joint closest to control/saw-cut joint. This will assure lateral movement transfer to membrane. Apply appropriate caulk to new??soft joint?. Bevel?Crack Suppression Membrane System (CSM 40)?edges with thin-set or mortar for a smooth transition to substrate.
  • Structural Cracks:?Center twenty-four (24) inch?Crack Suppression Membrane System (CSM 40)?over cracks that completely penetrate slab. If crack turns, cut and butt joint?Crack Suppression Membrane System (CSM 40)?to accommodate direction. Bevel?Crack Suppression Membrane System (CSM 40)?edges with thin-set or mortar for a smooth transition to substrate.
  • Non-Structural Cracks:?Center twelve (12) inch membrane over non-structural cracks such as hairline shrinkage cracks. If crack turns, cut and butt joint?Crack Suppression Membrane System (CSM 40)?to accommodate direction. Bevel?Crack Suppression Membrane System (CSM 40)?edges with thinset or mortar for a smooth transition to substrate.
  • Exterior and Wet Area Applications:?All joints and termination points of the membrane must be sealed with ? inch bead of SGM, Inc. approved Sealant. Smooth out sealant with flat side of trowel and let cure.
  • In-Floor Heating Systems:?Use?Crack Suppression Membrane System (CSM 40), full floor coverage, over in-floor, hydronic heating systems placed in poured gypsum/gypcrete or other lightweight products. Read?Product Guide to Surface Preparation (Underlayments for the Floor Covering Industry). Apply Interior Primer or Exterior Primer as required and install?Crack Suppression Membrane System (CSM 40)?as directed. Use?118.4?or better mortar for tile installation.
• Tile Warming Systems:?Use?Crack Suppression Membrane System (CSM 40), full floor coverage, over substrates where low-voltage tile warming systems are to be installed. Follow?Crack Suppression Membrane System (CSM 40)Information Sheet?guidelines. Secure tile warming system to membrane as directed by manufacturer. Use?118.4?or better mortar for tile installation.
• • Tile Setting Materials:?When installing porcelain, ceramic, and decorative stone tile or related products, a thin-bed, latex-modified mortar meeting?ANSI A118.4?must be used. Apply membrane over level coats, mortar, and mud beds. Key setting material into membrane with flat side of trowel. Re-apply mortar with notch side of trowel using minimum trowel size of ? inch x ? inch. Contact tech support for trowel size when using organic adhesives and epoxy mortars suitable for ceramic tile applications.

APPLICATION NOTES

For?Crack Suppression Membrane System (CSM 40)?Primer

Clean Up

Remove wet primer with a damp cloth and potable water. Use mineral spirits for dried primer, following manufacturer?s instructions. This primer is not freeze/thaw stable. Do not store below 35?F (thirty-five degrees Fahrenheit). If primer separates, shake well. If the product does not re-mix, do not use. Due to the increased adjustability of this primer to the membrane, a pull test, if needed, should be performed after 24 hours. Permanent bond should be established after 48 hours.

CAUTION

Not recommended for use on concrete floors with excessive moisture vapor transmission or excessive hydrostatic head pressure. Protect floors from traffic until the new floor is fully cured. Large format tile (LFT) installations may require extended cure times. Membrane and companion products must be protected from elements until the tile is installed, grouted and cured. SGM must be contacted for special instructions prior to the application of a leveler or patching compound to the membrane. Do not use petroleum-based cleaners or sealers for tile, marble, stone, or grout. Impervious tile (less than 0.5% absorption) requires a 48-hour cure time prior to grouting. Protect floors from heavy construction equipment during installation to prevent damage.

COVERAGE

• Membrane:?225 Square Foot / Roll
• Interior Primer:?375?425 Square Foot / Gallon
• Exterior Primer:?300?400 Square Foot / Gallon

MAINTENANCE

None required.