Mineral Render is a powder to be mixed with clean water in proper proportion. If excessively diluted, the render loses its strength and adhesion, and its structure becomes more porous.
In mineral render mortars, as in traditional thick layer plasters, the binding agent is gypsum, hydrated lime, hydraulic lime, potassium water glass or cement. Depending on the type of binder and the proportions in which it is used, the mortar is white or gray in color, often non-uniform, and requires painting.
It is also possible to tint such render in the mass, but the range of colors is very limited, and the resulting colors may vary in different batches. Therefore, mineral render is usually painted. For this purpose silicate and silicone paints are most often used. The former are cheaper and additionally strengthen the structure of the plaster, because the chemical process of their binding (silicification) makes the coating more durable over time. A very important factor here is the technological break needed for the render to dry. Depending on the type of selected paint, it takes from 3-5 days (silicate paint) to 3 weeks (acrylic paint with low vapor permeability).
Mineral facade render has no electrostatic properties, which makes it easier to keep the facade clean. However, the main factor determining the resistance of the render to dirt and the growth of microorganisms is the paint with which it will be painted. In addition, because mineral render is based on cement and additives that increase adhesion, it is resistant to significant temperature fluctuations and UV rays. It also shows resistance to mechanical damage. An important feature of mineral render is that it shows an alkaline reaction. It prevents the development of harmful microorganisms on the walls.
We are making mineral rendering in Manchester, Cheshire, and all surrounding areas.
Thin layer mineral render creates on the coated substrates a coat of high vapor permeability, thanks to which walls can “breathe”. They are recommended e.g. for thermal insulation based on wool, which requires from finishing layers low diffusion resistance (its measure is the material’s resistance to water vapour penetration) and in places where fire resistance is important. On the other hand, the specific character of mineral surfaces is also connected with certain drawbacks such as high water absorption and low impact strength. The first of them can be eliminated by painting such a plaster with silicate or silicone paint. On the other hand, the problem of relatively poor impact properties of render can be solved by simply applying it above the zone exposed to mechanical damage (plinths, low first floor).