Gypsum plaster is used when we need to obtain a smooth wall. However, it is not enough to buy a high-quality product. We also need to know how to properly apply this type of preparation. The universal nature of the plaster means that we can use it to cover surfaces that are covered with gypsum, cement or cement-lime plaster. We can also put the gypsum plaster on plasterboards. Another significant advantage is the neutral reaction of the substance, which prevents us from experiencing mold on the surface finished with gypsum plaster. Usually the material is applied to the walls, ceiling and possibly the floor. Much depends on the degree of humidity in a given room. It is best to avoid using such plaster in bathrooms. In addition, we should not apply too thick a layer of the preparation. Failure to do so may result in cracks in the finished surface.
The optimal way to apply gypsum plaster
The traditional method is to apply and smooth gypsum finish using a stainless steel trowel. If it is wide enough, we should be able to cover the entire wall relatively quickly. It’s a good idea to start the application from inside corners. Wait about 90 minutes between the application of the individual layers of gypsum plaster. The proper length of the break depends on factors such as the humidity and temperature of the application site. Many people forget that each subsequent coat of plaster must be thinner than the previous one. If we want to finish the wall quickly, it is worth getting a special gun with a spraying unit. Obviously, it takes some practice to start quickly and accurately applying the plaster with a gun. Stand at least 1 m from the wall finish, and apply the material in vertical stripes, starting from the top. Finally, it remains to spread the plaster to the sides. When the preparation is dry, it is good to check the condition of the surface. The question is whether it is smooth enough. In case of any imperfections, just use the abrasive mesh to sand the roughness. If we are satisfied with the results of our work, all that remains is to apply a coat of paint and then priming the substrate. However, it is necessary to wait at least 24 hours after finishing the application of gypsum plaster.
Are polymer plasters a good alternative to gypsum preparations?
They are produced using finely ground natural fillers, such as carbonate or dolomite flour. The role of the binder in this mixture is played by a polymer in the form of an aqueous dispersion. It is usually a derivative of acrylic acid. The polymer finishing coat must dry and harden on a given surface before the substance acquires its functional properties. This type of finish works exceptionally well during machine application. Due to the properties of this substance, we will not experience any significant material losses. With gypsum plaster, the mixed material binds inside the hoses attached to the sprayer. Greater resistance to stress and the flexible nature of the polymer mixture are other reasons why it is worth buying a polymer coat when we need to finish the so-called difficult surface. Room humidity does not affect the effectiveness of this type of plaster. For this reason, it will work, among others, in our bathroom or kitchen. For this reason, it is worth investing in both gypsum and polymer finishing coat, as both types perfectly complement each other.
The difference between cement and lime screed
In the former case, calcium plays the role of a binder in the plaster. The layer of this type of preparation should not be thicker than 5 mm. We can apply the lime plaster in a similar way as gypsum and polymer products. Manual puttying is the simplest and cheapest option. However, it will take much more time than if we had opted for a machine application. Another advantage of this preparation is the high adhesion of lime plaster. Its production does not require much effort. Like polymer models, lime plaster can be used in rooms with high levels of humidity (bathroom and kitchen). However, it must not be applied to gypsum surfaces. High resistance to the formation of mold and high vapor permeability make it easy to create a good microclimate in interiors finished with lime finish.
In turn, in the latter type of finish, the cement plays the most important role. The big difference is that the plaster is available in the form of a dry mix that requires mixing with water. Gypsum finishes look much better than cement models. However, they are not as durable. Cement screed will make our walls much more resistant to mechanical damage. They will cope perfectly in the bathroom and kitchen – humidity will not adversely affect their effectiveness as a surface finish. Do not sand such walls after the preparation has dried. So it should be on.