KNAUF PRIMER 90

A concentrated primer based on a synthetic resin dispersion with high resistance to alkaline environments. Designed for priming highly absorbent mineral surfaces inside buildings. Knauf Grundiermittel 90 evens out the absorbency of the substrate, prevents gypsum plasters from flaking off, and significantly enhances the durability of the plaster finish. A system solution for Knauf gypsum plasters. A solvent-free, vapour-permeable product, designed to be diluted with water in a ratio of 1:2 to a maximum of 1:5, depending on the absorbency of the substrate. This primer offers a cost-effective solution for large-scale projects, as the high coverage per container means that the price of Grundiermittel 90 per square metre of prepared surface is very competitive.

Properties of Grundiermittel 90

Knauf Grundiermittel is a professional concentrate based on a top-quality synthetic resin dispersion, designed to stabilise difficult mineral substrates. Thanks to its high resistance to alkaline environments, it retains its bonding properties even when in contact with strongly alkaline building materials. A key feature of the product is its ability to penetrate deep into the material’s structure – Grundiermittel enables effective surface reinforcement and standardisation of the wall’s properties. As a vapour-permeable agent, it does not form an impermeable barrier on the surface, but allows walls to exchange gases freely, which is essential for maintaining a healthy indoor climate. The key technical features of Knauf Grundiermittel 90 are:

• high concentration: can be diluted with water in a ratio of 1:2 to as much as 1:5, making the product extremely economical,
• equalising absorbency: Grundiermittel 90 eliminates the risk of water being released too quickly from the plaster into the substrate, thereby preventing the formation of cracks,
• health and safety: the solvent-free formulation means the primer is odourless and safe for workers,
• improved adhesion: drastically reduces the risk of the plaster coming away or becoming „hollow” once it has dried,
• yellow control colour: makes it easier to identify primed areas, eliminating the risk of missing sections of the wall.

By using the professional Knauf Grundiermittel 90 primer, you not only ensure a stable substrate, but also significantly reduce the amount of finishing material required during the subsequent stages of the work.

The use of Grundiermittel in the preparation of absorbent substrates

Knauf’s Grundiermittel 90 is indispensable for indoor work involving highly absorbent materials such as aerated concrete, ceramic brick or silicate blocks. It forms the foundation of the systematic preparation of the substrate for the application of Knauf’s machine-applied and hand-applied gypsum plasters. By effectively „sealing” the pores of the substrate, Grundiermittel ensures optimal conditions for the mortar to set, which results in high final strength and makes levelling the plaster easier. This product is designed for use on all types of mineral substrates requiring stabilisation prior to further finishing stages.

Knauf Grundiermittel 90 – technical information

• Coverage: approx. 0.1 kg/m².
• The product is packed on a KN-WO pallet. The cost of the pallet is 37.00 PLN per unit (net).
• This product is sensitive to low temperatures.
• Packaging: 15 kg bucket – number of items per pallet: 24.

How do you use Knauf Grundiermittel 90 primer?

Before commencing work, ensure that the substrate is dry, sound and free from contaminants such as dust or grease, and that its residual moisture content does not exceed 3%. Depending on the type and degree of surface absorbency, Knauf Grundiermittel 90 should be diluted with clean water in a ratio of 1:1 to a maximum of 1:5; for aerated concrete, a ratio of 1:2 or 1:3 is recommended, and for bricks and ceramic hollow blocks, a ratio of 1:4 or 1:5. The prepared mixture should be applied thoroughly and evenly using a roller, brush or spray, bearing in mind that the ambient and material temperatures must not be lower than +5°C. Given the concentrate’s coverage, the price of Grundiermittel 90 is exceptionally good value, particularly as a single bucket is sufficient to treat hundreds of square metres of wall, provided a minimum 12-hour drying time is allowed for the surface to dry completely before plastering. It is extremely important not to mix the product with other materials and to ensure proper ventilation of the room, which significantly speeds up the drying process and guarantees the system’s full effectiveness.