What kind of external render to choose? Some people consider this question already when reviewing house designs. There are a lot of possibilities since the different variants differ in texture, color, and texture. The choice of right render affects the building’s appearance but also the functionality and durability of the finishing materials. So what is the best external rendering system?
What is house rendering used for?
Many investors consider the available colors of the facade as the primary criterion in choosing a render. Of course, this is an essential aspect in terms of aesthetic impressions. However, we should not forget that exterior rendering walls can play a much more important part. In addition to its decorative qualities, it also has insulating applications.
House render is often an integral part of an external wall insulation system. In this context, we should remember its mechanical strength, weather resistance, and chemical properties. However, it is also necessary to match render’s type to the environment or technology of wall construction.
What are the types of modern renders?
The types available on the market can be divided into two main categories: thin-layer or thick-layer renders. What distinguishes each of them?
Lime render or cement render are made based on cement. The thickness of the traditional house rendering products exceeds 15 mm, so this variant is used primarily for rendering masonry and concrete. Standard cement renders provide with high mechanical strength and solid walls, but also little resistance to shrinkage.
What does this mean in practice? Such type of render often crack and absorb water much more easily. It makes the solution increasingly displaced by thin-layer render.
The advantage of thin-layer renders are their versatility. We can use them in one or several layers and on a surface with a previously laid thick-coat renders. There are several varieties, so their matching to the wall is not difficult.
- Mineral renders – low elasticity and water resistance compensates for high permeability and low price. Mineral renders are ideal for walls insulated with mineral wool or polystyrene foam.
- Silicone renders – the binder of silicone render is silicone resin. These types of render are considered one of the best, as they boast high elasticity, excellent permeability, and water resistance. They provide a beautiful appearance to the building for years, without the need for frequent renovations. Silicone rendering also have high resistance to overgrowth and the growth of microorganisms. The large selection of colors, also speaks in favor of this type of plaster.
- Silicate renders – are characterized by medium elasticity, self cleaning properties and resistance to water, while high permeability. They will perform best if applied over mineral wool insulation. Silicate plasters work well for buildings located in wetlands or the vicinity of bodies of water. Thanks to their encapsulated biocide content, they are highly resistant to overgrowth and will provide a beautiful appearance to the building for many years.
- Acrylic renders – like monocouche render, it is often chosen render finish. The binder of acrylic render is acrylic resin. These renders are distinguished from others by their very low vapor permeability. Therefore, we should apply them to dry walls. They are also not suitable for mineral wool insulation. Acrylic renders are ideal for medium air pollution. They are slightly less resistant to dirt than silicone external walls. High elasticity provides them with high resistance to damage.