CTS Cement
CTS Cement
Rapid Set


Hydraulic Cement-Based Water Plug

DESCRIPTION: Rapid Set® WATER STOP is a high performance, fast setting material designed to stop water leaks in concrete and masonry. Durable in wet environments, WATER STOP is a blend of Rapid Set hydraulic cement and specially graded fine aggregates. WATER STOP is non-metallic and no chlorides are added. Mix WATER STOP with water to produce a workable, high quality material that is ideal where rapid strength gain and high durability are desired. WATER STOP sets in less than 5 minutes and achieves structural strength in 1 hour.

USES: Use WATER STOP for cracks and holes in concrete or masonry surfaces such as walls, floors, swimming pools, cisterns, water tanks, basements, fountains, etc.

ENVIRONMENTAL ADVANTAGES: Use WATER STOP 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.

SURFACE PREPARATION: Application surface must be clean, sound and free from any materials that may inhibit bond, such as oil, asphalt, curing compound, acid, dirt and loose debris. Roughen surface and remove all unsound materials. Apply WATER STOP to a surface that is thoroughly saturated.

MIXING: Organize work so that all personnel and equipment are in place before mixing. Use clean potable water. WATER STOP may be mixed using 1 part water to 3 parts WATER STOP by volume. First, add the water into a mixing container or pail. Add WATER STOP and mix thoroughly with a trowel for 30 to 60 seconds to achieve a lump-free, putty-like mixture. Do not mix more material than can be used in 2-3 minutes. Do not retemper.

INSTALLATION: Using a trowel or gloved hands, quickly press WATER STOP firmly into the hole or crack. Maintain steady pressure until product stiffens, then release and finish.

CURING: No wet curing is required under typical conditions.

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 and use heated mix water.

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 and use chilled mix water.

YIELD & PACKAGING: WATER STOP is available in 25-lb (11.3-kg) box. 1lb (0.45kg) of WATER STOP yields approximately 14 in3 (229 cm3) and will repair approximately 26" of a 3/4" x 3/4" (1 kg for 146 cm of 2 cm x 2 cm) crack.

SHELF LIFE: WATER STOP 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 cement, 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 cement 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.

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

Water Plug: Stops water leaks quickly
Fast: Sets in less than 5 minutes
Strong: Structural strength in 1 hour
Concrete gray color
Excellent Bond: Superior adhesion to concrete and masonry
Multi-Purpose: Interior/exterior, horizontal, vertical, and overhead applications
Tested in accordance with:
MasterFormat® 2016
03 01 30Maintenance of Cast-in-Place Concrete
03 01 50Maintenance of Cast Decks and Underlayments
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

Set Time, ASTM C191 Mod.
Initial set4 minutes
Final set5 minutes
Compressive Strength, ASTM C109 Mod.
1 hour2500 psi (17.2 MPa)
3 hours3500 psi (24.1 MPa)
24 hours4000 psi (27.6 MPa)
7 days5500 psi (37.9 MPa)
28 days6000 psi (41.4 MPa)
Typical data produced at 70°F (21°C)
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