The most common method of finishing walls is plastering. You can choose between thin layer and traditional external plasters. Are you waiting for a facade renovation and don’t know which plaster to choose? Learn about popular types of external plastering finishes and their properties.
How to select the right external plastering material?
Traditional exterior plaster
Traditional exterior plasters are still a popular choice as they are thick, strong and have many benefits. They are a great protection against damage and heat loss, and they also provide sound insulation. They are used mainly to finish one- and three-layer walls and to renovate old plasters. However, not everyone is satisfied with the look of traditional plaster, that is why it is often additionally covered with thin layer plaster.
Among traditional plasters there are cement plasters, which are recommended especially when the surface is exposed to moisture or damage. Cement-lime external plastering finishes, on the other hand, are characterized by lower resistance but are more convenient to apply. Lime plasters are usually used on old plasters.
Thin layer external surfaces plastering
Thin layer plasters are most often used to finish insulated facades, as well as one-layer walls. Depending on the binder used, their properties are different. There are mineral, acrylic, silicone and silicate plasters available on the market.
Mineral plasters are available in the form of dry mixture that should be mixed with water. This type of external plastering finish is characterized by high pH (which means that it does not promote the growth of microorganisms), as well as vapor permeability and resistance to damage. In addition, mineral plasters are non-flammable and inexpensive. Due to their tendency to soak, they need to be painted, but this way you can get the color you like. The best will be silicone or silicate paints, which are vapor permeable.
Acrylic plasters, thanks to the use of polymeric binders, are flexible, waterproof and durable. They allow quick finishing of elevation but they are not suitable for fresh walls that need to give up moisture. They are characterized by low vapor permeability, that is why they are used mainly in insulations with foamed polystyrene. Their disadvantage is low resistance to dirt.
Silicone plasters are versatile, they can be used on a variety of substrates, both mineral and polymeric. They are resistant to moisture, UV radiation and dirt, and are vapor permeable. Unfortunately, under the influence of high temperature can be deformed.
Silicate plasters are characterized by the fact that over time they become more resistant. They are used on mineral surfaces. They are vapor-permeable, non-flammable and resistant to fungi and algae. However, these plasters are troublesome during application due to low resistance and absorption.
Smooth or decorative exterior plaster
The texture of plaster can be either smooth or decorative. The final appearance of the surface depends on the type of aggregate, including the size of its grains and how it is applied and rubbed. The most popular are mosaic plaster, rustic (scratched), spotted, brushed. Nowadays plasters which texture resembles other surfaces – wood, metal or brick – are fashionable.
The color of the plaster is equally important. Greater room for manoeuvre is offered by acrylic and silicone plasters that allow to obtain saturated colors of the elevation. It is worth remembering not to choose too dark colors on elevations facing south, as they attract sunlight and cause the plaster to heat up and deteriorate more quickly, while the color will fade over time.