Render, which covers the facade of our house, has an aesthetic function and a protective one, protecting the walls of the building from damage. What is the difference between acrylic and silicone renders? Which option will be better in your case? You can find out all this in our latest article. Read it to find out the advantages and disadvantages of both solutions and find the answer to whether you should choose acrylic or silicone render.
What is the difference between acrylic and silicone render?
Despite appearances, acrylic and silicone render differ a lot, so their choice is critical when finishing the house’s facade. The most crucial difference between these products is the degree of vapor-permeability, i.e., the so-called diffusion resistance. Acrylic renders are characterized by a high diffusion resistance, thanks to which they form a tight barrier for water vapor penetration. On the other hand, silicone renders are vapor-permeable.
What does this mean in practice? If you insulate your house with mineral wool, you should resign from using acrylic renders. Instead, choose silicone renders that can be used on wool and polystyrene foam. Acrylic renders are also not a good option if you are looking for a finishing layer for single-layer walls made of cellular concrete and expanded clay. This building product is not recommended for the renovation of damp walls because the acrylic layer prevents water evaporation. Interestingly, this rule applies not only to acrylic renders but also to acrylic facade paints.
Why are these limitations so important? Ignoring the degree of vapor permeability can lead to an increase in the moisture content of the thermal insulation material, causing it to lose its ability. However, this is not the only effect that can occur due to an inappropriate choice of render products. In such a situation, we create conditions that favor the development of fungi and bacteria; therefore, the effect of a wrong layer choice for the thermal insulation material may be a fungal infestation and fall off the render.
In what cases, therefore, are acrylic renders suitable? Suppose you insulate your house with foamed polystyrene in most cases. In that case, vapor-permeability will not be a problem because foamed polystyrene is characterised by a high diffusion resistance, which means that small amounts of water vapor may penetrate through it to the plaster. However, it is worth emphasizing that this is not a fixed rule. For example, if you insulate cellular concrete walls with a thin layer of polystyrene foam (approx. 5 cm), damp can condense under the plaster. For this reason, it is worth consulting a specialist who will carry out thermal and moisture calculations of the walls before and after they are insulated.
Similarities between acrylic and silicone render
Both types of render also have standard features. One of them is resistance to algae or algae growth. That is possible due to the encapsulated biocide content–this agent releases active substances and thus protects the render against overgrowth for many years.
In addition, acrylic and silicone render and mosaic render, which are also very popular on facades, are characterized by resistance to water and weather conditions and a wide range of colours. There are many colours available on the market, but if you can’t find a particular colour, some manufacturers offer the possibility of making a render for individual order.
Acrylic or silicone render? Which one to choose?
Which render to choose: acrylic or silicone render? There is no definite answer to this question, because the final decision depends on several factors: among others, the material with which you insulate your house, the location and whether the walls are damp or not.
Don’t forget that the external rendering manchester is not all about aesthetics. It performs primarily a protective function, protecting the building from the weather. That’s why you should be practical when choosing a render – so that in a few years you won’t have to render the walls again.