Durable silicone resin coating systems usually comprise a primer, a base coat and a topcoat. Self-priming paint is a particularly fast and economical solution which permits application of the primer and base coat in a single operation. SREPs are suitable for use on almost all substrates, irrespective of whether they are applied to new or undamaged facades, or during the course of renovation work. Different formulations serve to enhance special properties of the SREPs. For example, manufacturers offer water-thinnable, weather-resistant and light-fast glazes as well as aqueous exterior paints, matt paints with a high silicone resin content, matt, filled paints and self-cleaning paints in many different colors. Before purchasing your paint, ask which SREP is best suited to the requirements of your facade.

Silicone resin emulsion paints can be used on almost all types of walls. Before the paint is applied, it is essential to assess and test the substrate for defects. In Germany, suitably uncomplicated test methods routinely used on construction sites are described in the VOB (Construction Contract Procedures).

Suitable substrates for SREPs include:

• Mineral plasters: MG P I, MG P II, repair plaster
• Fair-faced masonry: natural stone, concrete, cellular concrete, sand-lime brick, bricks, half-timbered constructions
• Old coatings: emulsion paint, silicate paint, polymer plaster
• EIFS: polymer plaster, silicate plaster, mineral plaster

 

Important substrate preparation measures:

• The substrate must be clean, dry and intact.
• Clean old silicate coatings, stripping them if necessary.
• Strip off emulsion paint to allow water-vapor permeability, and clean the surface with a steam jet.
• Consolidate friable plaster with a solventless primer.

The constituents of silicone resin emulsion paint are listed in German industrial standard DIN 18363: silicone resin emulsions, polymer emulsions, pigments, fillers and auxiliaries. Such paint is described as being water-repellent (hydrophobic).

DIN EN 1062 classifies exterior paints according to their composition, appearance and physical properties. The binder that gives a paint its desirable properties also gives it its name. In the case of silicone resin emulsion paint this binder is a silicone resin. Among the physical properties listed in the standard is water-vapor permeability. SREPs are regarded as having high water-vapor permeability (sd < 0.14 m) and low water permeability (w < 0.1 kg/m²h^0,5).

In the “Normalisation Française” (AFNOR) FDT 30-808, paints are classified under Class10 C (NFT 36-005) as silicone resin emulsion paints if the proportion of silicone resin binder exceeds > 40 %. According to these guidelines, the terms silicone resin emulsion paint and silicone resin plaster are reserved for materials which contain silicone resin binders. The German VdL (Paint Industry Association) has published guidelines to ensure that consumers receive adequate objective information about the composition of construction coatings and paints and of related products, free of advertising considerations.