CTS Cement
CTS Cement
Rapid Set

Skim Coat

Patch, Skim Coat & Underlayment

DESCRIPTION: Rapid Set® SKIM COAT is a smooth, fast curing, sand-free, hydraulic cement-based floor underlayment. Use under flooring for patching and skim coating on interior and exterior projects. Apply from featheredge to 1" (2.5 cm).

USES: Use SKIM COAT to repair, level and smooth cement or concrete substrates, quarry tile, or APA rated interior-grade plywood prior to the installation of floor coverings such as VCT, sheet vinyl, carpet, tile, pavers, and other protective toppings.

ENVIRONMENTAL ADVANTAGES: Use SKIM COAT to reduce your carbon footprint and lower your environmental impact. Production of Rapid Set cement emits far less CO2 than portland cement. Contact your representative for LEED values and environmental information.

APPLICATION: Typical application thicknesses range from featheredge to 1/4" (0.6 cm) for large areas and up to 1" (2.5 cm) for small fill areas. Most floor coverings can be installed over SKIM COAT in 1-3 hours. Impermeable coverings and coatings can be applied over SKIM COAT in 16 hours. Please comply with instructions from the floor covering manufacturer regarding substrate moisture and moisture testing. For sections deeper than 1" (2.5 cm), use Rapid Set® Cement All®, Mortar Mix or Concrete Mix. Conduct a minimum of one field test using the prepared substrate and finished floor covering to evaluate the suitability of the materials and procedures.

SURFACE PREPARATION: Application surfaces must be clean, sound and free from any materials that may inhibit bond, such as oil, dirt, mastic, asphalt, sealing compounds, acids, wax and loose debris. Smooth concrete surfaces must be mechanically abraded by grinding, shot blasting or other approved methods. Acid etching is not recommended. Plywood surfaces must be structurally sound, rigid and properly adhered.

Do not use solvents or adhesive removers as means of cleaning the substrate. Application surface must be between 50°F (10°C) and 90°F (32°C). In temperatures above 80°F (27°C), pre-wet the substrate with water before applying SKIM COAT. Honor all moving joints and cracks.

MIXING: The use of a drill-mounted mixer is recommended. Organize work so that all personnel and equipment are in place before mixing. Use clean potable water. SKIM COAT may be mixed using 4.5 to 5.25 quarts (4.3 L to 5.0 L) of water per 20-lb (9.1-kg) bag. Use less water to achieve higher strengths. Do not exceed 5.25 quarts (5.0 L) of water per bag. Place water in the mixing container. While mixing, add SKIM COAT and mix for the minimum amount of time required to achieve a lump-free, uniform consistency (usually 1 to 3 minutes). Do not retemper or add additional water after initial mixing.

PLACEMENT: Organize work so that all personnel and equipment are ready before placement. After mixing, place quickly to allow for maximum finishing time. Do not install on frozen surfaces. To extend working time, use Rapid Set® SET Control® retarding admixture from the Concrete Pharmacy or cold mix water. SKIM COAT may be applied in temperatures ranging from 50°F (10°C) to 90°F (32°C). The working time of SKIM COAT is approximately 30 to 40 minutes at 70°F (21°C) ambient temperature.

COLD WEATHER: Environmental and material temperatures below 70°F (21°C) may delay setting time and reduce the rate of strength gain. Lower temperatures will have a more pronounced effect. Thinner sections will be more significantly affected. To compensate for cold temperatures, keep material warm, use heated mix water, and follow ACI 306 Procedures for Cold Weather Concreting.

WARM WEATHER: Environmental and material temperatures above 70°F (21°C) may speed setting time and increase the rate of strength gain. Higher temperatures will have a more pronounced effect. To compensate for warm temperatures, keep material cool, use chilled mix water, and follow ACI 305 Procedures for Hot Weather Concreting. The use of Rapid Set® SET Control® retarding admixture from the Rapid Set® Concrete Pharmacy® will help offset the effects of high temperatures.

CURING: Rapid Set® SKIM COAT does not require water curing or curing compound under moderate conditions at 70°F (21°C). In dry, windy or hot conditions, mist with water to maintain a continuously wet surface until the product has achieved sufficient strength.

YIELD & PACKAGING: SKIM COAT is available in 20-lb (9.1-kg) bags. One 20-lb bag will yield up to 600 ft2 (55.7 m2) as a skim coat or approximately 67 ft2 (6.2 m2) at 1/8" (0.3 cm) depth. Coverage may vary due to jobsite conditions.

SHELF LIFE: SKIM COAT has a shelf life of 12 months when stored properly in a dry location, protected from moisture, out of direct sunlight, and in an undamaged package.

USER RESPONSIBILITY: Before using CTS products, read current technical data sheets, bulletins, product labels and safety data sheets at www.CTScement.com. It is the user’s responsibility to review instructions and warnings for any CTS products prior to use.

WARNING: DO NOT BREATHE DUST. AVOID CONTACT WITH SKIN AND EYES. Use material in well-ventilated areas only. Exposure to cement dust may irritate eyes, nose, throat, and the upper respiratory system/lungs. Silica exposure by inhalation may result in the development of lung injuries and pulmonary diseases, including silicosis and lung cancer. Seek medical treatment if you experience difficulty breathing while using this product. The use of a NIOSH/MSHA-approved respirator (P-, N- or R-95) is recommended to minimize inhalation of cement dust. Eat and drink only in dust-free areas to avoid ingesting cement dust. Skin contact with dry material or wet mixtures may result in bodily injury ranging from moderate irritation and thickening/cracking of skin to severe skin damage from chemical burns. If irritation or burning occurs, seek medical treatment. Protect eyes with goggles or safety glasses with side shields. Cover skin with protective clothing. Use chemical resistant gloves and waterproof boots. In case of skin contact with cement dust, immediately wash off dust with soap and water to avoid skin damage. In case of skin contact with wet concrete, wash exposed skin areas with cold running water as soon as possible. In case of eye contact with cement dust, flush immediately and repeatedly with clean water, and consult a physician. If wet concrete splashes into eyes, rinse eyes with clean water for at least 15 minutes and go to the hospital for further treatment.

Please refer to the SDS and www.CTScement.com for additional safety information regarding this material.

LIMITED WARRANTY: CTS CEMENT MANUFACTURING CORP. (CTS) warrants its materials to be of good quality and, at its option, will replace or refund the purchase price of any material proven to be defective within one (1) year from date of purchase. The above remedies shall be the limit of CTS’s responsibility. Except for the foregoing, all warranties expressed or implied, including merchantability and fitness for a particular purpose, are excluded. CTS shall not be liable for any consequential, incidental, or special damages arising directly or indirectly from the use of the materials.

CANCER and REPRODUCTIVE HARM - www.P65Warnings.ca.gov

Excellent Bond: Bonds to concrete, plywood, brick, block and more
Versatile: Apply skim coat to 1" (2.5 cm)
Great Workability: Easy to apply, workable for 30-40 minutes
Fast Setting: Walk on in 1-3 hours
Interior/Exterior: Mold and mildew resistant
Easy To Use: Just add water; no primer or curing compound required
MasterFormat® 2016
03 01 30:Maintenance of Cast-in-Place Concrete
03 01 50:Maintenance of Cast Decks and Underlayment
03 54 16:Hydraulic Cement Underlayment
CTS Cement Manufacturing Corp. 12442 Knott St. Garden Grove, CA 92841 Tel: 800-929-3030 | Fax: 714-379-8270 Web: www.CTScement.com E-mail: info@CTScement.com
icon icon

USGBC and related logo is a trademark owned by the U.S. Green Building Council and is used by permission.