In the process of carrying out repair and capital construction work, the question of which plaster - cement or gypsum to choose remains relevant. These binders remain in demand for leveling, preparing and facing surfaces before finishing decorative work. Each of these materials has its own advantages and disadvantages, so making a decision is not easy.
The main landmarks should be highlighted:
- ease of installation;
- operating conditions;
- price;
- terms for completion of work.
Comparison by area of use
If you still cannot decide which plaster to choose - cement or gypsum, you should consider eachof them. For example, the first one is suitable for outdoor and indoor work, is not afraid of moisture and temperature changes, and is often used to level slopes, walls and other surfaces. You can use the material even in basements and unheated rooms.
This mixture is also good because it is suitable for finishing in rooms with high humidity, as well as processing concrete structures to increase its thermal insulation properties. This option is the ideal masonry mortar when building from foam blocks and aerated concrete.
A distinctive feature of the cement mixture is high adhesion. In addition, the composition is highly durable and durable. It is chosen during capital construction and restoration of old surfaces, which is important when materials are compatible. This factor is very important, because cement does not adhere well to the following surfaces:
- painted planes;
- wood;
- plastic.
Use restrictions
When deciding which plaster to choose - cement or gypsum, you should also pay attention to the fact that the first has some limitations in use. For example, this should include a complex application process and a long drying time. The work should be carried out in several stages. First, the material is applied by spraying, then by throwing, then rubbed and polished.
To geta perfectly flat surface, you should work hard, because not all craftsmen have the necessary skills. But with gypsum, such problems usually do not arise. It dries pretty quickly, which cannot be said about the cement layer. This may take about three weeks, even under those conditions if you applied a thin layer. The surface turns out to be porous, it is poorly suited for decorative finishes and has a dark shade, which means that it needs to be puttyed and further sanded. Cement mixes are not decorative. Compounds with special additives are an exception.
If you cannot decide which plaster to choose - cement or gypsum, you should consider both. The second is more plastic and does not shrink. The consequence is that it is an ideal option for leveling interior walls. Drying is faster, and it is not necessary to putty the wall, because the structure is smooth without it.
Why choose plaster
The color of the plaster is white, it does not show through paint or wallpaper. Such a composition is in contact with coloring pigments, it can be chosen as an independent decorative finish, it can take the desired shape, so it can be used to create three-dimensional patterns.
If you want to know which is better - gypsum or cement plaster, you should consider the features of both. For example, gypsum has a low weight, which means that it can be applied without the risk of overload. However, attention should be paid to poor water resistance, which does not allow us to callthe composition is universal. Under the influence of moisture, gypsum begins to break down, so the plaster is not used for outdoor work.
Main Features & Comparison
Among the advantages of cement plaster, durability and strength should be highlighted. Such a composition is well suited for finishing and restoration outdoor work, excellently withstands mechanical and other external influences. With aerated concrete, such mixtures adhere well, as well as with smooth surfaces such as artificial and natural stone. Application can be carried out on previously plastered walls. This mixture is well suited for foam blocks, for example, for their masonry and decoration, and the consumption on porous material is minimal.
Cost and moisture resistance
It is impossible not to highlight the low cost. The cement variety of plaster is 2 times cheaper than gypsum. This applies to ready-made compositions and mixed independently. It is also important to take into account moisture resistance, which is the main advantage of the described solution. This property allows the use of cement plaster as a material for finishing slopes, lining bathrooms, bathrooms and kitchens. Gypsum under the same conditions can only be used with a certain protection of the surface with tiles. This feature allows the use of cement compounds for outdoor work.
The temperature of their use varies from + 5 to + 30 ˚С. A 10 mm layer takes about 13 kg per square meter. When applied manually, consumptionwater is 0.14 liters per kilogram. Aggregate grains have a fraction of 0.63 mm or less.
When applied to brick or reinforced concrete, the minimum layer thickness is 5 mm. The maximum thickness for brick is 25 mm, for concrete or reinforced concrete - 15 mm. The time of use of the finished mixture is 2 hours. If it is important for you to decide which is better - cement-sand or gypsum plaster, you should also consider the characteristics of the latter. Among the main features, ease of installation and speed of work should be highlighted. Drying occurs 2 times faster than in the case of cement compositions. In this case, the layer thickness can be the same. Gypsum mixtures are easy to process, they do not undergo sedimentary processes, and when cured, cracks form in a minimum amount when compared with cement plasters.
Additional features of gypsum
Plasticity is also important for craftsmen. Without much effort, you can apply the material to any surface, distributing it on the wall with the desired layer thickness. The load on the structures is low. It is also necessary to highlight vapor permeability and environmental friendliness. The plaster is breathable. It is safe for humans and favorable for the microclimate in the house. You may also be interested in heat and sound insulation abilities. The structure is light and porous. It retains heat better than others and prevents the penetration and spread of extraneous noise. Due to these properties, gypsum mixtures do not need to be reinforced. Exceptions are layers from 50 mm.
With vertical wall materialdoes not drip, it holds its shape well. Application reduces repair time. No special construction skills are required for work. Reviews say that gypsum saves money, because it is consumed in a minimal amount.
Feedback on the features of the application. Applying cement to plaster
Many consumers are wondering if cement putty can be applied to gypsum plaster. From experience, this idea is not the best solution. Cement mixtures mainly act as base surfaces, as they are quite rough to use, so obtaining an even base under such conditions will be almost impossible, according to home craftsmen.
Cement plaster on a gypsum wall is also not recommended, as contact with water will cause an alkaline reaction. Cement is a strong base, and gypsum does not like alkalis. Theoretically, such an option for carrying out work is possible, the cement composition can be laid on a gypsum wall, but when wet, the lower layer will lose strength, and the material on top will receive low laminar strength. Therefore, consumers emphasize that anhydride and gypsum bases should be classified as complex.
If you are still concerned about the question of whether it is possible to apply cement plaster on a gypsum wall, then you should take into account that when drying, in this case, there will be a huge stress, this will cause the materials to tear off the layer from the surface. Consumers say that gypsum is better to plaster exclusivelyplaster.
Applying plaster to cement
Reviewing the previous example, you should have understood that when carrying out such work, delaminations can occur. You can work in reverse order. It is permissible to apply gypsum plaster on a cement surface. The gypsum will then take moisture out of the cement, making the chemical reaction impossible.
Gypsum plaster is not as durable as cement-sand plaster, but it is stronger than lime plaster. These works have their own nuances. Gypsum plaster must be applied using a primer treatment. For finishing gypsum plaster, it is not recommended to use tiles laid on tile cement adhesive, as this will also contribute to the destruction of the material.
Characteristics of gypsum-cement plasters
A mixture of gypsum and cement plaster is sold as a composition of the Starateli brand MIXTER. The mixture has a gray color and is made on the basis of cement, gypsum, sand and imported additives. The material is used for leveling the surfaces of ceilings and walls inside the premises for various purposes. The degree of humidity in this case can be any. The thickness of the applied layer varies from 5 to 60 mm. The average consumption of the mixture per square meter is 1.1 kg. The layer thickness is 1 mm.
