Dirt stores moisture and pollutants and prevents the surface drying out. This is why it should always be removed. The following applies: as careful as possible, as intensive as necessary! As renders are generally painted, they should be cleaned with water and a detergent containing surfactants. Surfactants comprise hydrophilic (=water-friendly) and hydrophobic (=grease-friendly) constituents. Water insoluble dirt has an affinity to the hydrophobic part and are included in transport processes by the entire molecule.
Article No. 0671
Surfactant solution for removing grime, dirt incrustation, dust, oil and grease deposits
Article No. 0676
Special detergent for removing green growth on terraces, stone floors and walls