Plaster of extruded polystyrene foam: how and how to plaster polystyrene foam

Plastering is an essential step in improving the strength and appearance of building facades made of extruded polystyrene foam, or simply XPS foam. XPS foam is a common material in contemporary construction because it is lightweight and has good thermal insulation qualities. To achieve a smooth and long-lasting finish, plastering over this material calls for caution.

It’s crucial to properly prepare the surface before adding plaster to XPS foam. Cleaning the foam to get rid of any dust, dirt, or debris should come first. By doing this, the plaster is guaranteed to stick firmly to the surface. After that, use a primer made especially for XPS foam. The primer prolongs the life of the finish by strengthening the bond between the plaster and foam and sealing the surface.

Select a plaster with a pliable and permeable composition for XPS foam. Because XPS foam can expand and contract with temperature changes, flexible plasters are less likely to crack. Moisture can escape through breathable plasters, preventing a buildup that could eventually harm the foam. These characteristics guarantee the plaster’s integrity and its ability to adequately shield the XPS foam underneath.

Plastering XPS foam requires methods that are similar to traditional plastering, but they take the foam’s characteristics into account. Using a trowel, begin by evenly applying a base coat of plaster over the entire surface. To keep control over the thickness and smoothness of the application, work in small sections. To get the desired texture and look, apply a finish coat once the base coat has set but is still slightly tacky. Applying this last layer evenly and smoothly will guarantee a seamless finish.

Examine the plaster’s surface for flaws or places that might require touch-ups after it has completely dried. To get a uniform appearance, gently sand down any rough areas and add more plaster layers as needed. Lastly, to improve the plaster’s resilience to weathering and durability, think about sealing or coating it.

Why is it necessary to finish?

• solar radiation;
• some life;
• Atmosphere pressure.

The new material is extremely brittle as well. If the corners of an unprotected plate get dented and are already brittle.

Polystyrene foam needs to be protected because of this. Because purlilation is a cheap technique for decorating facades, it is frequently used as a protective layer.

Necessary tools

A set of tools must be acquired in order to apply a plaster solution to polystyrene foam in a timely and quality manner. For this, you’ll need:

1. Container for kneading solution.
2. Perforator (used both for the preparation of the mixture and for fixing polystyrene foam).
3. Brush or spray gun for applying a primer.
4. A sharp knife for cutting the reinforcing mesh and insulation plates.
5. Wide spatula for applying the solution to the surface.
6. Narrow spatula.
7. Grater for aligning the layer.

Since it is unlikely that everyone will have such a set, remember to purchase instruments in advance for the supplies when you go.

Types of plaster materials

It is necessary to choose a specific plaster composition for this material. Not every plaster works well with polystyrene foam. Certain options include parts that instantly demolish the foam. Thus, make sure to ask the consultant in the store whether or not to proceed with the insulation work.

Mineral

The least expensive choice. consists of mineral fillers, sand, and cement that enhance the layer’s qualities after it solidifies. sold as dry mixtures that need to be diluted with water in a specific ratio before use. Ratios The packaging is always disclosed by the manufacturer.

Developing such a solution on your own is totally doable. Simultaneously, they purchase cement and sand separately, measuring the required volumes of each ingredient individually during the preparation process. Thus, work becomes more challenging, particularly if half-portions need to be prepared in order to decorate a small area.

Mineral plaster is not as good. Due to the poor adhesion of polystyrene foam, application is challenging. The insulation is coated with a unique primer to improve adhesion, and tiny bags are applied to the whole surface.

Acrylic

An improved, though more costly, plastering mixture substitute. As this plaster has high indicators of adhesion with any material, it doesn’t require any special preparatory work when applied to polystyrene foam.

Chemical additives and acrylic resins make up the majority of the ingredients. These combinations were developed specifically for facade decoration following insulation. It can therefore support a range of loads. Long-term processing preserves the surface’s beauty and ease of cleaning.

You can use acrylic plaster to quickly create decorative compositions or to create textures. For instance, inclusions in Karkoed rub together to form grooves. By utilizing various grout techniques, you can produce a unique design.

Plastering extruded polystyrene foam presents a visual appeal and practical advantages for homeowners considering facade options. This post explores the key methods and factors to take into account when plastering polystyrene foam. Understanding these techniques guarantees a long-lasting and aesthetically beautiful finish, from surface preparation to the application of appropriate plaster materials. Successful facade projects require an understanding of the plastering process for polystyrene foam, whether the goal is to achieve a desired architectural style or to improve insulation properties.

Features of such finishes

Plastering over this insulation is challenging for the following reasons:

• Smooth surface – the solution can slide, if it is still applied, then it can crack or fall off after drying;
• The absence of hygroscopicity – moisture from plaster solution is not absorbed into the polystyrene foam, but remains in the decoration, which significantly extends the drying time;
• The difference in the values ​​of the temperature expansion of the insulation and finishing material, which causes cracking of the last.

Preparatory work should be done and everything should be handled as precisely and clearly as possible to prevent such issues:

1. On the surface of the polystyrene foam, walk with a needle roller or make notes with a sharp knife. Thus, you get deepening, where the solution will be able to "catch".
2. Be sure to cover with a primer that increases adhesion.
3. You can’t do without a net for reinforcement.
4. The maximum thickness of the applied layer cannot exceed 5 mm.

These suggestions will facilitate the application of a plaster solution and lessen the chance of cracking.

How to plaster extruded polystyrene foam – technology

It is imperative to finish the heater slabs as soon as possible if they are mounted on the building’s walls. Experts advise taking this action right away after the material has been fixed with glue that has dried.

Conducting calculations

Purchasing plastering supplies with a margin is preferable. I wouldn’t want to leave my job in the middle of work to go get another bag. However, how can one determine how much material is required? Do the following easy calculation to accomplish this:

• calculate the area of ​​the processed walls without taking into account window and doorways;
• On the packaging of the decree, approximate consumption of the mixture per square meter.In different compositions, it ranges in the range of 4-6 kg;
• We multiply the indicated value by the processed area and get the required amount of the mixture;
• We add another 10 % to the resulting value – this will be the final amount.

Preparation of a plaster mixture

The manufacturer usually provides instructions on how to prepare the solution, so pay attention to the advice and packaging. When plastering polystyrene foam for the first time, start with a small knead to get the feel of the material and the procedure.

1. A dry mixture is poured into the container.
2. In small portions add water.
3. You can mix manually, use a punch with a nozzle or a construction mixer.
4. When the consistency completely suits, leave the solution for 5 minutes to ripen and mix again.

In certain instances, a little more slurry must be added to the solution than what the instructions specify.

Playing a reinforcing grid

The slopes and corners are processed first. To accomplish this, cut the reinforcing mesh into strips so that there is a minimum of 10-15 cm of material on each side of the corner.

• A thin layer of solution is applied to both sides of the corner;
• Apply a grid and smoothed out of the corner so that the material is completely deepened into the solution;
• If the length of the piece was not enough, they make a overlap 10 cm, you can’t stick it into the joint.

They also begin at the wall’s entire length. They operate in the same sequence:

1. The wall is covered with a solution.
2. The width of the strip slightly exceeds the size of the reinforcing grid.
3. Put the material and smoothed with a wide spatula or ironer.
4. The next layer of the grid finds on the previous one, 10-15 cm.

Grouting a plaster mesh

The initial layer ought to be entirely dry. The surface is then treated using a grater with sandpaper and gentle circular motions. By doing this, minor irregularities will be eliminated and less alignment solution will be needed.

Surface alignment

After making a fresh solution, we align the plastered polystyrene foam. They now use a wide spatula in their work:

• a small amount of solution is typed on a wide spatula;
• with arc movements from top to bottom are applied to the wall;
• layer thickness of not more than 3 mm.

Verify that the surface is as level as it can be.

Grout of the second layer

The grout is only applied once the layer has dried fully. Use sandpaper and the same grater. They alone can choose fine grain to eliminate tiny imperfections. If not, you could easily sabotage the entire project.

Primer

This stage is not one that should be ignored. The decorative layer will either be applied incorrectly or rapidly become unappealing if the base is not primed. The finishing technique determines the primer’s composition:

1. Further decorative plastering – uses a composition in which there is quartz sand, it helps to increase adhesion.
2. Staining – composition without sand, makes the base even more.

Finishing

After selecting one finishing technique over another, they behave logically in accordance with the manufacturer’s plan. Applying the material has its own subtleties for both decorative plaster and painting. As a result, in order to learn how to do everything correctly, you need to read a few more articles.

Extruded polystyrene foam, or XPS, plastering is a cost-effective way to improve the aesthetic appeal and insulation of the front of your house. XPS boards are perfect for do-it-yourself projects because they are lightweight and manageable. Make sure the surface is dust-free, dry, and clean before applying plaster. A bonding agent is applied to improve plaster adhesion.

Select a plaster mix that has been specially made for polystyrene foam. Because of their flexibility and breathability, these mixes stop cracks and let moisture out. With a trowel, start by evenly applying a base coat to the entire XPS surface to create a smooth foundation. Let the first coat completely dry before adding more layers.

Choose a plaster for the finishing coat that goes well with the design of your house. While smooth finishes give a more modern appearance, textured finishes can add depth and character. To ensure uniform coverage, carefully and evenly apply the final coat. For optimal effects, shield the recently plastered surface from sunlight and precipitation, depending on the weather.

Maintaining the integrity of the plastered XPS facade requires regular maintenance. To stop water from seeping in, look for any indications of wear or damage and fix any chips or cracks right away. A plastered XPS facade can add curb appeal to your house and offer long-lasting insulation against changing weather conditions if cared for properly.

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