House rendering is the easiest and fastest method of finishing techniques. Thin coat render is the most commonly used render for this purpose, which appeared with the introduction of the light-wet technology of external wall insulation.
We can choose from different types of render in various colours. However, when considering the colour or texture, we should also take into account its resistance to weather conditions and fungal and mold growth. Today, we have a durable rendering system at our disposal, adapted to various requirements of investors.
External wall insulation and render choice depending on the environmental conditions
All the thin layer renders available on the market are rain resistant and water vapor permeable, which means that moisture does not accumulate in the wall, so we should make the choice of render after an analysis of the immediate environment.
Mineral render finish are very durable, and the binders contained in them harden over time and improve the properties of the render. Such house rendering does not get dirty very easily, that is why they are worth using in cities, where the air is usually polluted. Silicate (silicate) and silicone render also have the same properties.
Polymeric renders are water-resistant but quite tight, i.e. they have less vapor permeability. A popular variety is acrylic render, which is recommended for finishing houses standing by roads with heavy traffic. Acrylics reduce the stress caused by vibrations caused by car traffic, limiting the risk of micro-cracks and deamination of the render. When choosing a polymer render, buy one that contains additives increasing resistance to UV radiation. Acrylic renders have such properties, and they do not fade when exposed to sunlight, even if their colours are very intense.
Silicates are flexible render and can therefore cover small shrinkage cracks formed in traditional solutions. Silicate renders react with the carbon dioxide in the air, increasing their durability. This is particularly important in polluted urban environments.
Silicone and silicone-resin render like stone cladding increases the durability of masonry. In comparison with standard cement renders they are water-resistant but block the passage of water vapor from the building. They do not bind dirt: when dirty, they’re like self-cleaning render (the so-called lotus effect). Such type of render does not require frequent maintenance.
Durable modern renders resistant to mold and fungi
If there is a risk of organic stains, algae, or fungi, it is worth using mineral or silicate renders that have a strong alkaline reaction (pH about 12), which makes the development of microorganisms practically impossible. The binder which is lime is responsible for the increased pH of mineral renders; in the case of silicate render, the binder in the form of potassium water glass also has an impact on alkaline pH.
Another advantage of silicate and mineral plaster is good vapor permeability, which also limits the development of fungi and algae. Silicone renders may also be used, which contain additives of biocides limiting the development of microorganisms. If you decide to use acrylic renders in areas at risk of biological corrosion, it is worth choosing a product with added biocides.
Colours and textures of mineral or silicone render influence its durability and cleanliness
If your house is located close to factories, traffic routes, or green areas, consider the texture of the facade. The coarser the grain size of the render, the rougher the facade texture will be. Unevenness and depressions in the external walls will be a place for gathering dust particles, dirt, as well as micro-organisms, which not only affect the cleanliness of the facade but may also become a source of mold and mildew. In this case, it is worth choosing a smooth elevation structure.
The colour palette of thin coat renders is very rich, but the basic ones are white and grey. These are also practical coloured render – dirt on such a facade is less visible, but if you decide on white, instead of plain, choose a shade broken up with another colour.