Features and Benefits

Rigid 1-component cementitious waterproofing slurry


  • waterproof
  • water permeable
  • suitable for drinking water tanks
  • strong reduction of capillary absorption of water
  • increases surface protection
  • frost resistant
  • economical application
  • can be applied by brush, trowel or sprayed
  • resistant to negative water pressure
  • protects standard concrete structures

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Ceresit CR 65 1-C Rigid Slurry can be used on the horizontal and vertical surfaces of buildings, structural components, tanks and swimming pools with a water depth of ≤ 10 m. Suitable for the subsequent waterproofing of old buildings or components on the negative side. CR 65 can be applied on rigid, crack-free surfaces made of concrete, brick-work, renders and screeds.

CR 65 is perfect to improve concrete surface resistance, even having different concrete qualities and structures. CR 65 passed the tests according to EN 1504-2 standard. Can be used as well as final layer on substrates without mechanical impact.

Ceresit CR 65 is a part of Ceresit cementitious slurries range with Hydroslide Effect.

Step by step

Substrate preparation


The mineral substrate must be even, solid, load-bearing, clean, crack-free and free of substances that may impair adhesion. The surface must have a rough, open pored structure with good grip. All edges must be cut off or chamfered. Cove all corners with a hollow moulding of at least 4 cm radius. Repair any defects, screed over rock pockets and fill mortar joints, e. g. with CT 23 Repair Mortar or CN 91 Wall & Floor Repair Mortar. Enlarge the cracks and fill them with cement mortar alternatively, pressure-grout the crack with CK 740 Epoxy Resin. If the brickwork is uneven with numerous projections and defects, produce a levelling render made of cement mortar. Make sure to thoroughly prewet the prepared substrate. When waterproofing wall and foundation areas indoors or outdoors, e. g. in the case of rear penetration of moisture, pre-treat the areas with CO 81 Silicifying Fluid. When waterproofing from negative side, the substrate must have sufficient mechanical strength.



Sprinkle CR 65 into clean water and stir until completely free of lumps. The waterproofing coat must always consist of two layers. First, apply a heavy coat of Ceresit CR 65 with a well-loaded brush. The surface must either have been prewetted or pretreated with CO 81. The silicifying fluid must have soaked into the substrate, but must be still wet. When the first layer has reached sufficient surface strength, prewet the substrate again and then spread the waterproofing slurry with a float or apply two thin slurry coats with a ceiling brush. The maximum layer thickness of each coat applied is 5 mm. If work is interrupted for more than 24 hours, add CC 81 Synthetic Resin to the slurry before applying the next coat. Protect the waterproofed surface against too rapid drying; keep it moist for at least 24 hours. Excess mortar can be removed with water while still fresh, but hardened material can only be removed mechanically.