Preconditions

Preconditions for a correct impregnation

It has to be ensured that the material is absorbent and air dry prior to impregnation. All absorbent materials can be treated with solvent and water based impregnations based on TEGOSIVIN^® products.The more porous and absorbent the material is the higher is the efficiency. An air dry substrate is an important precondition in order to achieve maximum penetration depth.
Wet substrates already contain water inside the capillaries.This reduces the uptake of impregnation material and results in reduced water repellency. A uniformly light surface is a good indication of the fact that the substance is dry enough to treat.

The material to be impregnated must be absorbent The material to be impregnated must be air dry Damaged stones have to be replaced or repaired The masonry joints have to be without any damages The facade has to be free of visible cracks The expansion joints have to be tight and resistant to solvents The roof, window and door joints must not be damaged Gutter and drainage pipe connections must be tight The wall should not have rising damp Algae and moss growth has to be removed prior to impregnation The facade has to be clean (dirt leads to a lower absorption) There must be no efflorescence Glass, windows, door frames and other sensitive materials (particularly solvent sensitive areas when using solvent based systems) have to be protected against splashes Plants located in the vicinity of the treated areas have to be covered Fresh concrete and the mortar joints must have cured, i.e. impregnation should be carried out after 3 - 4 weeks at the earliest

Cleaning of old facades

When impregnating old facades cleaning is necessary in most cases. Efflorescence has to be removed mechanically followed by cleaning with water or steam jet. Chemical cleaners should be applied on a water saturated facade in order to avoid deep penetration of the chemicals into the masonry.They have to be carefully rinsed off since they may cause discoloration in combination with the impregnation or may affect the curing reaction. The wet facade should show neutral reaction for at least 1 hour (to be checked with pH paper). The facade has to be allowed to dry prior to impregnation.