Suggestions & Solutions

Issue & Solution: Humidity on exterior walls


Moisture problems on external walls due to rain are a common phenomenon, especially if no care has been taken to create a waterproof plaster or if they are painted with low-quality paint.

Such problems are even more pronounced on north-facing walls, with cracks or on walls located close to the sea. Dealing with these problems can be done easily and effectively even after the fact, when painting them.


ISOMAT FLEXCOAT is the ideal solution for waterproofing walls against rain. It is a high-quality, highly elastic, water-soluble paint, based on acrylic elastomeric resins. It provides full waterproofing, coverage of cracked surfaces, excellent resistance to washing and allows the breathability of the structural element.

Substrate preparation

  1. The substrate must be dry and free of friable materials, dust, oils, etc.
  2. Imperfections in visible concrete are plastered with PLANFIX and PLANFIX-FINE resinous cement mortars.
  3. Cracks or joints are filled, after expanding to a width of at least 3 mm, with the elastoplastic acrylic mastic ISOMASTIC-A or with the two-component elastic putty FLEX-COVER.
  4. This is followed by priming the surface with the FLEX-PRIMER acrylic primer.
  5. After the primer has dried, ISOMAT FLEXCOAT is applied.

Application of ISOMAT FLEXCOAT

Before use, ISOMAT FLEXCOAT is stirred slightly and used as is or diluted up to 5% with clean water. The material is applied with a roller, brush or airless gun in two layers. The second layer follows after the first has completely dried.