Salt contaminated substrates - restoration with THERMOPAL
Key Facts
There is a high incidence of dampness and salt contamination within the substrates in old buildings. In order to restore these surfaces both professionally and for a long time then the salt contamination must be analysed exactly in order to be able to adopt the appropriate product system. The THERMOPAL system developed for such occurences is not only suitable for restoring such surfaces but also simultaneously facilitates the restoration of mould contaminated surfaces. An old building becomes a truly restored building project.
Salts located within masonry work function hygroscopically and migrate to the surface, as this evaporation zone has a low moisture content and good conditions for crystallisation exists. This leads to the destruction of the plaster/render surface.
Brush apply ESCO-FLUAT once or twice to the exposed masonry work to saturation (dependent on the salt contamination and porosity of the substrate). The damaging salts are converted to sparingly soluble salts and cannot be carried forward into the new,
freshly applied plaster.
Apply THERMOPAL-SP, up to a maximum thickness of 5 mm, to cover half the surface (approx. 50% surface coverage) in preparation for the render coat in accordance with the rules governing rendering techniques. Lightly pre-wet the substrate as necessary in order to guarantee a good bond.
Apply THERMOPAL-GP11 in thicknesses from 10–30 mm (with thicker coats in more layers). Strike off each previous coat with a plasterer’s darby. Immediately the plaster stiffens roughen up horizontally and allow to dry.
Apply a single layer of THERMOPAL-ULTRA up to a max. of 3 cm. After allowing to stand for an adequate amount of time, the surface can be grid floated or rubbed down. Rubbing too early encourages the binder to concentrate at the surface which can cause shrinkage cracks and impede the vapour permeability of the plaster layer.
Apply the fine grain mineral-based compound THERMOPAL-FS33 by trowel to the required thickness up to a max. of 3 mm. Once the surface has dried rub down with a foam rubber board, felt board or sponge board.