Monolithic wall decoration, regardless of the type of material used, will always win in terms of reliability and durability in front of the restored defective surface. But it is far from always justified to completely dismantle the old coating to apply a new one, so you should not refuse restoration measures. The most common operations of this kind are grinding plaster. What kind of operation is this? This procedure is in the nature of minor repairs in the form of sealing a damaged finish. Accordingly, it has its own characteristics and performance nuances.
Grinding Features
This technique can be compared with a partial primer or spot repair of a defective area. But if you can cope with shallow flaws and putty with a light grout mixture, which will also provide an equalizing effect, then the grind aims to repair deep damage, but with a small area. Does this mean that the work is simplified? In a sense, yes, since the volume of laying can not be compared with the complex design of the walls with a new coating. On the other hand, the restoration of individual sections always entails a violation of the geometry of the surface - the same threat is especially manifested during the grinding of plaster. What does it mean? Laying a thick layer of mortar in a small area can cause problems with surface correction. Accordingly, the accuracy of applying the mass and further leveling will be important. The problem is that mechanical alignment may not give the expected result, since the fluid mixture after work is still deformed under its own load.
Preparation for work
The crucial stage, during which the target work area is prepared. The surface is cleaned of dust, dirt and other foreign particles. You can perform light grinding, which will remove easily peeling layers of the old remaining plaster. Do not overdo it in this operation, as strong fluctuations can affect the structure of the adjacent whole coating. If, after stripping, the elements of metal reinforcement appeared, they should first be repaired with special putty, acceptable for use in contact with metal surfaces. Such quality as the adhesiveness of the grouting of the plaster of the interior will be important. This is the property that determines the adhesion of a new solution layer to the base surface. As removing dirt from the damaged area increases adhesion, the composition of the putty putty should at least organically interact with the solution of the applied plaster. However, the selection of a suitable mixture should be given special attention.
What solution is needed?
The main question in choosing a dry mix for grinding - what should be the type of base? It is better to refuse the modified formulations immediately, since the plasticizers included in them in small areas in direct contact with the foreign mixture can display their qualities in different ways. After all, do not forget what it means to grind the plaster? This is the inclusion of a new solution in an existing coating structure. A traditional cement composition may seem to be a universal option, in which both the adhesion is high and the strength will allow forming a reliable seal. But, the cement-sand mixture has a long hardening period, and this is an undesirable characteristic for the mass laid flat on a small area.
The best solution is a gypsum mortar. In addition to environmental friendliness and fast hardening, such a basis will allow performing a plastic and resistant to shrinkage grinding of plaster. What will this give in practice? Firstly, it will remove the problems of post-processing damage when it will be necessary to perform leveling and corrective operations. Finishing finishing is performed once, after which the laid mass is not deformed. Secondly, gypsum will make it possible to patch up even difficult and hard-to-reach areas precisely due to plasticity. In some conditions, such a plaster can be used as a replacement for putty.
Grinding technique
The operation is preferably performed manually with a spatula with a small rule for surface correction. After 2-3 hours after laying the base mass with a complete seal of the defective area with the help of a trellised grater, it is necessary to remove influxes and all kinds of irregularities. By the way, grinding of wall plaster can be carried out in several layers, if the embedment depth exceeds 25 cm. In this case, the first layer should be applied without intermediate treatment. Moreover, to increase adhesion with a subsequent layer, the initial surface should be roughened. And after the second pass, the excess is removed and the texture of the coating is leveled.
Grinding in combination with jointing
If it is necessary to make a deep seal of the crack, it is advisable to perform a preliminary alignment. This is a kind of stripping, but in a more advanced technological version. The jointing procedure is to remove the remnants of problematic concrete along the edges in the crack zone. Finishers advise to blow out the defect cavity as much as possible, which will stop its further spread. In the process of grinding plaster with cracking, a chisel with a hammer is used to remove old finishes and a construction vacuum cleaner to blow through the fault. The rest of the operation is performed according to the standard solution laying scheme.
Features of work on the street
Repair of the facade coating has its own specifics, for which the following amendments are made:
- The solution should be made on a composition intended for outdoor use. In particular, silicate filler will allow for high-quality grinding of the facade plaster. What does this mean in terms of operational effect? At a minimum, protection from precipitation will be provided with strengthening the structure of the problematic coverage area.
- Do not apply plaster on a dirty surface. To clean the facades use a special high-pressure wash.
- Sealing is carried out with a mandatory preliminary primer in 2-3 thin layers. At the final stage, the alignment of the plaster can be done with waterproof sealant.
Conclusion
As a repair and restoration operation, regrinding allows you to preserve the general structure of the base coat for a while, but do not overestimate it. The heterogeneity of the finish structure in itself creates favorable conditions for the future formation of new cracks. Therefore, specialists use the concept of temporary grinding of plaster. What does it mean? Damage and coating defects are repaired only for a certain period until the next major overhaul. Otherwise, there is a risk already in the first months after work to detect signs of the same cracks in the place of grinding through a new decorative finish.