Features and Benefits

2-component solvent-free, fiber-reinforced bitumen thick coating for waterproofing buildings


  • Flexible  
  • Crack-bridging
  • Rapidly-drying
  • Easily workable
  • Amount required (depending on type of use):
  • Ground moisture, non-accumulating seepage water 4.2 kg/m2
  • Pressurized water 5.6 kg/m2

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Ceresit CP 43 is used for waterproofing structures against ground moisture as well as water pressing from outside up to 3 m immersion depth. Also suitable for waterproofing containers and for fixing insulation, drainage and protection boards. CP 43 can be applied on all mineral substrates, e.g. concrete, plasters, screeds and brickwork. It is resistant to all aggressive substances naturally present in the soil.
Tested at the German Institute of Construction Engineering

Step by step

Substrate preparation


Substrates must be level, solid, load-bearing, clean, dry or slightly damp, and must have been pre-treated with a suitable Ceresit primer. Chamfer all edges at an angle of 45°. Cove inner corners with a scotia of at least 4 cm radius using either CT 23 Repair Mortar (drying time approx. 3-4 hours) or Ceresit CP 43 (max. 2 cm radius, drying time at least 12 hours). Please refer to the Technical Data Sheets of CP 41 Bitumen Emulsion or CO 81 Silicifying Fluid for further information on priming and substrate preparation. Use CP 50 Joint Sealing Tape to prepare movement and separation joints between buildings.



Mix the 2 components with a slow-running electric drill (approx. 400-600 rpm), preferably equipped with an anchor stirrer. First, briefly stir the liquid component. Then add the entire powder to the liquid component and mix until a homogeneous, lump-free compound has been produced (mixing time: at least 2 minutes). After the priming coat has dried, apply a uniform layer of Ceresit CP 43 using a trowel and a float. Layer thickness depends on the water load type.