Plaster for external work on concrete: photos and videos

The durability and aesthetic appeal of plastering concrete surfaces externally depend greatly on the materials selected. The hard weather demands a plaster that not only provides a smooth, appealing finish, but also endures the elements.

This post will examine the kinds of plaster that work best for concrete projects outside and provide helpful advice on how to apply it. You will discover helpful images and videos to help you along the way and guarantee that your project is finished with expert results.

Whether you’re finishing a new building or remodeling an existing one, knowing your options for exterior plaster can have a big impact on how your project turns out. Let’s examine the specifics and discover how to create a surface that is both aesthetically pleasing and long-lasting.

Selecting the appropriate plaster is crucial for outdoor concrete surface plastering in order to guarantee weather resistance, longevity, and a smooth finish. This article makes it easier for anyone to achieve professional results by offering helpful advice on choosing and applying plaster for exterior concrete work. It is backed up by images and videos that show each step of the process.

Technology of plastering concrete walls.

Preparation of the base.

The state of the working surface is crucial because weak, loose, or peeling wall fragments will erode fresh plaster.

The standard technology for plastering concrete walls involves several stages of concrete, reinforced concrete, and monolith preparation for plastering:

1. Removal of weak areas. If the concrete base has poorly reinforced coatings, swelling, peeling, etc., they should be removed. Fragments that hold well, but are susceptible to pressure should also be cleaned off: sooner or later they will collapse anyway. Everything that wobbles, moves and does not hold well must be knocked down, cleaned off. The base must be completely stable.
2. Cleaning. The concrete must be completely exposed. Therefore, all the layers covering it (pieces of putty, paint and whitewash) are completely cleaned off.
3. Leveling. Small potholes (3-5 cm sq.) can be filled with cement-sand mortar as is, larger ones require reinforcement.

Moreover, reinforcement (wire, mesh) is required for leveling variations in wall thickness (beginning at 1.5 cm).

1. Checking evenness. Before applying plaster, it is better to once again make sure that the walls are perfectly even using a rule and a building level. If necessary, beacons made of cement-sand mortar are applied to the recesses.
2. Priming. The concrete surface is prepared with primers. They perform several functions:

• Dust removal.
• Filling the pores of loose surfaces to avoid increased absorbency.
• Increasing (and more uniform distribution) of wall adhesion.

With primer, you can improve the plaster’s level of wall adhesion. This is critical to the layer’s longevity. It is applied following the filling of potholes and cracks and the full drying of the leveling concrete inserts.

1. For block-concrete walls additional preparation is recommended – gluing. The smooth surface of the slab will not allow the plaster to hold securely. As a preparation, a solution of tile adhesive is used, which is applied with a notched trowel.

Application of concrete plaster.

Sand concrete plastering can be done either independently or using a "purchased" mixture.

Preparation of the solution.

To prepare the solution, use a trough or concrete mixer.

In order to prepare plaster for external concrete work, follow these steps:

1. Sifting sand. For plastering – this is essential, since small stones, clay impurities and organic residues (leaves, roots) will interfere with the leveling of the plaster.
2. Mixing. First, I combine the sand with cement: pour sand and cement into a container and mix them thoroughly.
3. Adding water is done in small portions. It is very easy to pour it over: at the last moment, when the solution is almost ready, every 200 grams of water can be fatal.

Mix well after adding each portion.

1. Determining readiness. The solution should be uniform (in color, structure). Its consistency should be such that it easily slides off the trowel, spatula, leaving the tool almost clean.

The type of cement determines the proportion of sand to cement. For M500, for instance, five buckets of sand. However, the concentration of the cement increases by 1 position if it is not fresh (1 h. Cement: 4 h. sand).

Using homemade sand concrete for plastering walls is the easiest finishing that a non-professional builder can do.

Plastering procedure.

Installing a beacon system.

You must install beacons—elements that protrude from the wall to a height that corresponds to the plaster’s thickness—if you want the plaster layer to be flawlessly smooth.

1. Gypsum. Small fragments of gypsum mortar are applied to the wall in such a way that they do not protrude beyond the surface of the future plaster, but exactly match it. Gypsum is convenient because it dries and hardens quickly.
2. Cement-sand. You can also organize landmarks from concrete mortar. Such beacons are simple and cheap, but are suitable only for small areas of work.
3. Wooden. For large volumes of plastering (room, apartment), it is more advisable to install vertical lathing. Such beacons are more effective, more convenient.

The least expensive option is wooden slats, but they have certain drawbacks such as unevenness, deformation, and swelling when exposed to moisture.

1. Metal profile more reliable. After finishing the work, the profile does not need to be removed.

Expanded clay concrete blocks can be plastered without the need for reinforcing. Beacons do not need to be painted on walls. For a beginner, this can be rather difficult, though.

Splashing.

Splashing is used to apply the first layer of plaster. A thin solution, no thicker than 0.5 cm, is used for this; it has the consistency of thick sour cream.

The layer’s job is to provide superior adhesion to the surface by effectively penetrating its pores. It is made possible by:

• Consistency of solution.
• Method of application (the solution is not spread, but thrown on with “slaps”).

Spray doesn’t need to be leveled.

When applied over a reinforcing mesh, liquid plaster for cellular concrete adheres to the wall more effectively than thick plaster.

Priming.

Bottom layer. It is between one and 1.5 cm thick.

Applying the primer involves throwing. Starting from the bottom of the wall, work is done starting from the corner. The task is made easier when using beacons because the solution—which is thicker than when spraying—is applied over the full width of the space between the beacon slats. The solution should be applied in excess (excess is removed by sliding along the beacon slats in the same manner as guides).

The primer is sprayed on almost dry; fingers should not cause the concrete to crumble.

Covering.

A liquid solution is poured over nearly dry soil to apply the top layer. By filling in large sand grains, tool scratches, and micropores, the desired surface will be smooth and perfect.

Use only fine material for the cover, sifted through a sieve with 1.5 x 1.5 mm cells; otherwise, perfect evenness won’t be achieved. A cement solution without sand is used to create plaster for painting (instead of putty).

Grouting.

Grouting is done without waiting for the top layer to completely dry; instead, the surface is leveled and smoothed using the tool’s movements (grater). Two varieties of grouting exist:

• Circular. Movements in a circle (for right-handed people – counterclockwise).
• Running, running. The tool is moved in wide, horizontal or vertical swings.

Running grouting eliminates traces left by the grater’s circular motions, and vice versa. As a result, the highest possible plaster quality is obtained by switching between the two techniques.

Using a trowel packed with felt or felt, final alignment can be accomplished.

Features of applying gypsum plaster.

Gypsum coatings ought to be put on a concrete surface that has been deeply penetrated by primer. As a result, the clutch of heterogeneous layers will grow.

Since the plaster mix does not consist of just gypsum mixed with water, gypsum plasters are not made by hand; instead, they are purchased pre-made.

Utilized similarly to cement-sand plaster.

Selecting the appropriate plaster for exterior concrete work is crucial to maintaining the durability and aesthetic appeal of your walls. You can choose the plaster that best fits the requirements of your project by being aware of the various types that are available.

As the images and videos demonstrate, using the right application techniques is just as crucial as selecting the right material. You can achieve a smooth and long-lasting finish that will shield your concrete surfaces for many years by following these steps.

In the end, taking the time to choose the ideal plaster and apply it correctly will pay off by providing your external walls with the long-needed protection and visual appeal.

Video on the topic

Strong and cheap facade plaster made of cement and sand .

Concrete paint for external work