Cembond 945 is a surface waterproofing for mineral surfaces. By adding Silex Polymer, we achieve outstanding strength and long-term durability.
The set sealant adheres to all mineral substrates—including damp ones—through a cross-linking reaction. It is perfectly waterproof while allowing for significant water vapor diffusion.
Coatings with CEMBOND membranes seal against positive and negative water pressure, prevent concrete carbonation, increase sulfate resistance, and protect the building material from the penetration of damaging salts.
The Cembond 945 coating is tough and hard, yet easy to apply due to its soft-plastic consistency. This coating also allows for visually appealing, smooth surfaces.
Characteristic: Reactive, organic-mineral system
Components: 2 (powder and mixing liquid)
Appearance: Grey-beige, pasty mass
Density: Approx. 1.8 g/ml (fresh mortar)
Mixture A : B: 100 : 40 parts by weight
Dilution: With water if required. Maximum addition 20%
Consumption: 1.8 kg per mm layer thickness / m²
Pot life: 90 minutes at 20°C
Minimum layer thickness: 2.5 mm
Diffusion resistance: 800 - 1000 (water vapor)
Pressurized water tightness: Up to a maximum of 7 bar
The CEMBOND M types are not reprofiling mortars. To avoid stress cracks, the recommended layer thickness must not be exceeded, or products may be "leanened" by mixing with coarse quartz sand if necessary. However, leaned products are no longer waterproof and must therefore be recoated with at least two layers of undiluted product.
Freshly applied coatings with CEMBOND-M must not be subjected to pressurized water.
When laying tiles and slabs on waterproofed surfaces, ensure the covering is fully bedded.
Coatings made of CEMBOND-M are not diffusion-tight and are therefore not suitable as waterproofing under parquet, laminate, or other diffusion-tight floor coverings and coatings. This also applies to waterproofing under screeds if they are subsequently provided with a vapor-tight top covering.
Coatings with CEMBOND-M are not wear-resistant layers and must therefore be protected from mechanical stress.
Application
Exterior waterproofing of building surfaces in contact with the ground. Against ground moisture, seepage and perched water, and also pressurized water up to 70 meters water column.
Interior waterproofing against water pressure from the outside - up to 40 meters water column.
Interior waterproofing of containers for water, wastewater, liquid manure, etc., up to 40 meters water column.
Waterproofing under ceramic coverings in bathrooms, showers, on balconies, and terraces.
Can be applied to standard concrete, fully jointed masonry* (including gas or aerated concrete), and cement-bound plasters (MG III plaster). All substrates must be clean, free of dust, contaminants that impair adhesion, cement laitance, and be sufficiently load-bearing. Sharp edges must be broken, formwork burrs removed, and honeycombs and depressions filled.
Before coating, the substrate must either be thoroughly pre-wetted to create a uniform, matte-damp surface, or the area must be primed with CEMBOND-956. For this purpose, Cembond 956 is diluted with water at a ratio of 1:2 - 1:3 and applied generously.
Processing
CEMBOND-M products consist of a fine-particulate solid and the appropriate mixing liquid. For processing, the solid and liquid are thoroughly mixed using a stirrer until a smooth, homogeneous mortar is formed.
This mortar mass is immediately ready for use. Its consistency is soft-plastic, allowing the material to be applied easily and well with a notched trowel (square notch, 4mm) and subsequently smoothed. In this state, application with spray equipment for fine plaster—e.g., the Putzmeister Sprayboy®—is also possible. For thin spatula applications or to achieve a brushable consistency, the mixture can be further diluted with up to 20% water.
The coatings must be applied in at least two layers with a total minimum thickness of 2.5 mm. The total layer thickness should not exceed 5 mm. The thickness of the layers must be uniform to avoid issues caused by uneven drying. CEMBOND surface waterproofings are not leveling plasters.
If coarse unevenness, damaged areas, etc. need to be leveled, the mixed mass should be "leanened" by adding 20-40% quartz sand (grain size approx. 0.5 - 1.2 mm, depending on the grading curve and the desired effect). Such repair mortars still possess the excellent adhesion to the substrate typical of CEMBOND, but are no longer liquid-tight and must therefore always be recoated with a sufficient thickness of undiluted product.
The formation of cracks in the building structure must be prevented by constructive measures. Waterproofing of expansion joints must be carried out using suitable, permanently elastic systems. In the case of pressurized water, special technical solutions such as the installation of special joint profiles, sealing with flexible sealing tapes, backing injections, etc., are necessary as accompanying measures. These must be determined on a project-specific basis.
Waterproofing of buildings generally requires the waterproofing to be arranged on the water side (positive waterproofing). The waterproofing should be brought up approximately 30 cm above the final ground surface. When waterproofing from the inside (negative waterproofing), particularly careful substrate preparation is necessary to ensure optimal adhesion of the coating to the building material.
A visually appealing surface effect is achieved by working with a wet paint brush (ceiling brush, flat brush) or by smoothing with a trowel held at a flat angle.
During processing and for at least two days thereafter, the sealant must be protected from intense heat, direct sunlight, rain, frost, and drafts. It is recommended to keep the fresh coating moist for at least 24 hours.
The products are non-flammable, but the liquid components are sensitive to frost. When stored in a cool, dry, and frost-free place, CEMBOND products have a shelf life of at least 12 months.
System accessories for Cembond 945 M - Surface waterproofing for mineral surfaces
Cembond M 947 flex – flexible sealing slurry for surface waterproofing
HydroBloc Si 709 – siloxane concentrate for horizontal barriers
Seal Fix expansion mortar 930 for sealing injection holes
Silex Suspension 931 – application-optimized injection mortar for void filling
Container: 17.5 kgAttention: Frost-sensitive material. Can only be shipped at >5°C.
We deliver exclusively to selected EU countries. The stated prices apply only to the European mainland; no delivery to German or European islands. We deliver all goods curbside.
