Dismantling of plaster, types of its defects, expediency of work and preparation, how to remove the finish and dispose of waste. Dismantling of plaster is one of the stages of construction repair. If you need to update the walls, removing the old covering in whole or in part will be simply necessary. Such work should be performed, adhering to the recommendations and established rules, which you will learn about today from our material.
Types of plaster defects
Plaster defects differ in appearance and reasons for their appearance. In addition, they are divided into operational and technological, the difference between them is that the former appear over time, and the latter - immediately after the coating is installed. Both of them can have the same appearance:
- Small bumps… These are bumps that appear on the surface of the plaster due to the use of hydrated lime, which has not been sufficiently matured. The bulges produce unqualified particles of material.
- Cracks… They appear in case of an overdose in solutions of astringent components or with poor-quality mixing. In addition, cracks in the plaster can arise from its forced drying, especially when exposed to summer sunlight.
- Flaking… It occurs when plaster is applied to a dry base or to a less durable bottom layer of the coating.
- Bloating… Such a defect can be caused by the application of plaster to a substrate oversaturated with moisture.
Feasibility of removing plaster from the walls
Complete dismantling of old plaster is not always justified. The need for such work depends on certain factors. One of them is the composition of the plaster:
- Clay… Most often, such a coating is used for finishing heating shields or fireplaces. When it peels off or breaks down, the thermal conductivity of the base material is violated, therefore, in this case, the clay plaster must be replaced.
- Limestone… Such plaster must be removed when it is weakened or it is necessary to apply a cement-sand coating to the wall in the future.
- Gypsum… Its dismantling is carried out due to the destruction of the coating.
- Cement… The need to remove such plaster often arises due to mistakes made in the preparation of the solution, or violation of the rules for working with it.
- Polymer… For the most part, such plasters are very durable and suitable for applying any coatings to them. Therefore, the need to dismantle it may be associated with mistakes that were made during the application of the composition and led to cracking or peeling of the finish.
Another factor is the condition of the coating layers. It can be the reason for the complete or partial dismantling of the plaster from the walls. If it has retained its strength only in a small area, it will be reasonable to completely dismantle the old coating. But if the defects are minor, only problem areas can be cleaned on the wall.
When planning a new coating with the removal of old plaster, the main rule should be adhered to: it should not be stronger than the previous one, since otherwise, giving shrinkage, the new layer can destroy the lower finish, which has lower stresses.
Therefore, the third factor in the expediency of dismantling the old plaster is the composition of the planned coating. So, for example, cement plaster cannot be laid on gypsum plaster, regardless of its condition, for the above reason. On clay plaster, except for the clay itself, nothing can be applied at all, the layer will not stick. But on top, it fits perfectly on any base.Reliable cement-sand plaster can be used for laying any coating on it.
Preparatory work before dismantling the plaster
Before removing old plaster, it is necessary to assess the quality of its structure and adhesion to the wall. To do this, tap the entire surface with a rubber mallet. In places where the coating does not adhere well, a dull sound will be heard. Such areas should be marked with chalk for further work with them.
The presence of dampness in the room and sections of the walls with moisture showing through on them indicates a weak layer of plaster. In such cases, problem areas and problem areas adjacent to them by 0.5 m in each direction are cleaned of the old coating.
It happens that when the wallpaper is removed, a layer of plaster comes off along with it. This is a good reason to completely remove it from the entire wall.
Any dismantling should be approached very responsibly, despite the fact that this work does not require special qualifications. The most important thing in it is compliance with safety measures, since often flying fragments of brick, concrete or a cloud of dust can damage your own health.
Therefore, before removing the plaster, it is necessary to stock up on means of protection for the eyes, skin and respiratory tract. A respirator or gauze bandage can protect the respiratory system, goggles - the eyes, and construction gloves and heavy overalls - the skin from damage. In addition, for safety reasons, it is recommended to temporarily turn off the power supply of the room in which it is planned to remove the plaster from the walls.
When choosing a working tool for removing the coating, you need to focus on the thickness of the old plaster layer, the type of its material and the requirements for the cleaned base. The standard kit should include: a spatula, an ax, a pickaxe or hammer, a metal brush, a long chisel, a hammer drill with a nozzle, a broom, a broom and a scoop, a bucket, a wide brush and garbage bags.
Important! Removing the plaster can greatly simplify the availability of an angle grinder or special tools such as AGP and Flex.
The main methods for removing plaster from the walls
Various types of plaster can be removed from the walls by hand or using power tools. One method or another is used depending on the characteristics of the coating.
Removing plaster by hand
Before removing the plaster from the wall, it should be well moistened. This softens the surface and reduces the amount of dust. Pieces of plaster that do not adhere well to the surface of the base can be pryed off with a steel trowel, removing them. Strong areas of the coating are knocked off with a chisel, ax or pickaxe. Special care must be taken when removing plaster from plasterboard partitions and walls. Such a base is easy to damage, therefore strong blows are excluded. In this case, it is convenient to work with loops. This tool is very similar to a honed trowel. First, you need to remove the weak areas of the coating. After cleaning small fragments of the wall, access to the side face of the plaster layer will open. Then a significant part of the coating can be removed by driving a cycle under its end.
If it does not respond well, you can use a chisel or chisel for trimming. In order not to destroy the surface of the drywall sheet, the chisel should be held at an angle, gently tapping on the tool with a small hammer.
Removing plaster mechanically
The mechanical method of removing the plaster is used after manual cleaning of the weak areas of the coating. Tough plaster that is difficult to knock down by hand can be removed with a hammer drill or angle grinder. The hammer drill must be equipped with a chisel blade and switched to the “chiseling” mode. It should be borne in mind that its work is accompanied by a high level of noise.
The sander is equipped with a diamond-coated stone disc.With its help, plaster can be cut into small squares, and then removed in parts with a chisel or perforator. When removing the coating mechanically, it is recommended to use an industrial vacuum cleaner. It will be able to practically eliminate the appearance of dust in the working process.
After cleaning the wall, it is necessary to remove small areas of plaster residues. To do this, you can use a wire brush or any of the mentioned power tools equipped with a suitable attachment.
Removing decorative plaster from walls
Silicate and polymer decorative plasters are strong enough, so it is very difficult to remove them. It is recommended to use the mechanical method described above. If such coatings can serve as a reliable basis for other wall finishes, then they can be left.
It is much easier to dismantle decorative plaster from gypsum with your own hands. It has a loose structure and is very sensitive to moisture. You can take advantage of these properties. Half an hour before removing such plaster, the walls must be well wetted. Acetic acid can be added to warm water to help soften the material and make it more pliable.
Since the removal of gypsum plaster is a rather dirty process, the floor should be covered with plastic wrap before starting work. Removing the coating can be done with a paddle width of 130-150 mm. Having determined the required cutting angle and sufficient force, you can begin to remove the decor protrusions on the wall surface.
If the base is made of plasterboard, the cycle must be held at an angle so as not to damage it. After removing the relief from one section of the wall, you can proceed to the next. After finishing the dismantling of decorative plaster on all walls, you need to clean them from debris and dust, and then wipe them with a damp cloth.
Clay and lime plaster is removed in a similar way.
How to remove lighthouses after plastering
There is no definite answer to the question of whether beacons are removed after plastering. However, it is believed that beacons left in the wall can lead to rust on its surface and even cracks. But no one can give one hundred percent guarantee in favor of "for" or "against", since it all depends on several important factors.
The first is the quality of the lighthouses. Metal profiles made from counterfeit low-quality raw materials can become rusty under conditions of the plaster layer. When choosing products from leading manufacturers, this is hardly possible.
The second factor is the thickness of the galvanized layer on the lighthouse. With diligent leveling of the plaster and repeated application of the rule on the profiles, a thin layer of galvanized steel can wear off. Then the upper part of the profile will become sensitive to corrosion.
And, finally, the third factor is the humidity of the room in which the plaster is made on the lighthouses. In a dry room, the likelihood of rusting is extremely low, especially with a well-functioning ventilation system.
As for the cracks, here the opinion is unequivocal. The metal profile left in the plaster is a kind of reinforcement. Therefore, if you do not try to hang a picture or a shelf on him, he will behave well.
However, in order to save yourself the slightest risk, the lighthouses after plastering the walls can be removed, and the cavities left by them can be sealed with mortar.
Disposal of waste after dismantling the plaster
As the dismantling work is completed, a lot of construction waste accumulates in the room. Diligent workers pack it in bags on time so as not to stumble over pieces of broken plaster. These bags must then be taken out somewhere. But the problem of recycling construction waste is quite acute. Time and opportunity to take it out is not always available.This is often due to the workload of utilities, the remoteness of objects from city dumps, and many more reasons.
For apartment buildings, there are no other options besides the removal of such garbage. Utilities usually prohibit loading it into a shared container. The reason is clear: the weight of the plaster, broken off from 1 m2 walls, averages 20-25 kg. Therefore, a container filled to the brim with such a load may be overwhelming. Therefore, the filled bags are loaded into the vehicle separately and not in the first place.
For private houses, the problem is easier to solve: dismantling waste can be used on the farm. Pieces of cement-sand plaster can be used as a filler for concrete mortars when pouring areas and sidewalks.
The removed clay plaster can be kept on the site for later use, especially since there is no need to knead a new solution, since the proportions of clay and sand in it have already been determined and implemented. It remains only to soak the material.
Gypsum plaster can be used as bulk insulation for floors of various buildings. Remains of limescale are good for pouring into the ground in areas of the site where tree growth is undesirable.
How to remove old plaster - look at the video:
Subject to all these rules, the work you have expended will be justified by a good result and there will be a real opportunity to complete the business you have started within the specified time frame. Good luck!