Today there is plenty of materials for dry construction. The most popular, convenient and versatile, is the gypsum plaster Rothband Knauf. With polymer additives in its composition, Knauf plaster is ideally suited for walls and ceilings that have both concrete and brick bases.
A feature of Rothband gypsum plasters is that they can be applied to any, even very smooth, surface. You can’t do this with ordinary cement plaster, because it will simply fall off the wall.
You can find out exactly what characteristics Rothband gypsum plaster has, and where it is used, from this article in the construction magazine samastroyka.ru
Gypsum plaster Rothband Knauf: consumption, characteristics, description
Plaster gypsum plaster Knauf Rotband - is a dry mix based on gypsum with polymer additives. It is due to polymer additives that the maximum adhesion of the Rotband gypsum plaster with the surfaces being trimmed is ensured.
The main purpose of this plaster is the decoration of walls and ceilings in residential premises with a moderate degree of humidity. It should be noted that building gypsum absorbs moisture from the environment quite well, therefore it is advisable to use gypsum gypsum plaster only in those rooms where normal humidity is constantly present.
Rothband plaster has a white color and a fine-grained structure. This allows you to perfectly prepare the surface of the walls and ceilings in the house for painting, for example, or decorating them with wallpaper. Consider the main characteristics of plaster.
Characteristics of gypsum plaster Rotband Knauf 30 kg
As mentioned above, Rotband gypsum plaster incorporates polymer additives. In turn, their presence in the mixture makes it well stick even to a very smooth base.
As a result, the thickness of the applied layer of plaster can be from five to fifty millimeters. Typically, for the preparation of gypsum plaster Rothband Knauf, 18-19 liters of ordinary tap water are taken per 30 kg of dry mix. After that, the mixture is qualitatively mixed by means of a construction mixer until a homogeneous, desired consistency mass is obtained.
Of the main technical characteristics of Rothband plaster, it should be noted that:
- Dry plaster mix fraction, not more than 1.2 mm,
- The thickness of the plaster layer is 5-50 mm,
- The consumption of gypsum plaster Rotband Knauf with a plaster layer thickness of 1 cm is approximately 8-9 kg per square meter,
- The total drying time of the Rotband plaster, at least seven days,
- The time for which you need to work out the finished stucco mixture, about half an hour,
- The compressive and bending strength of the Rotband plaster is 2.5 and 1.0 MPa,
- The shelf life of Knauf Rothband gypsum plasters, when properly stored, is approximately six months.
So, we will consider the process of applying Rothband gypsum plaster on a previously prepared base of a wall or ceiling.
Work with gypsum plaster Rothband Knauf
How to make Rothband plaster has been discussed above. To do this, for one bag weighing 30 kg, you need to take about 18-19 liters of clean water, then add the dry mixture to it and mix thoroughly with a construction mixer. It is important to withstand the solution for at least five minutes, after which it can be used.
You should be aware that those surfaces that strongly absorb moisture, such as those made of silicate brick, must be primed before applying Rotband plaster. As a rule, Knauf primer of the same name is used for these purposes. However, if completely smooth walls are plastered, it is better to use the special Knauf-Betokontakt primer for priming.
So, after the surface is cleaned of dirt and dust, and also primed (the primer must completely dry), you can start applying gypsum plaster Rothband Knauf. To this end, use a metal trowel and a long construction rule.
First, the Rotband plaster pounces on the wall from the bottom up, after which, with unhurried zigzag movements, it is stretched along it using the rule. After leveling, you should wait about half an hour, after which you can wipe the plaster layer with a felt grater for plaster.
Rothband Properties
Rotband based on gypsum powder. Gypsum is a natural mineral. Its hardness is 3 points on the Mohs scale with a maximum of 10. This makes it easy to crumble a stone.
In the powder, gypsum easily absorbs moisture, that is, it is hygroscopic. Sim differs most sedimentary rocks. Sedimentary refers to the gradual subsidence and compaction of sediments at the bottom of water bodies.
Among the deposits there are many remains of living things, for example, shells and bones. Their main component is calcium. He predominates in the gypsum formula. Her chemical record: CaSO4 * 2H2O. Accordingly, gypsum is aqueous calcium sulfate.
Pure gypsum white. It turns out the same rotband. Plaster may be slightly pinkish, gray. Deviation from the standard is not considered. There are natural impurities in gypsum.
If the mineral mass is cleaned from mechanical types of sand and clay, then it is unrealistic to get rid of the stones built into the chemical formula. Given that the proportion of foreign elements is negligible and does not affect the quality parameters of the plaster except for its color, impurities are left.
The color of the mixture is not indicated on the packaging of Knauf plaster. You can determine the shade, if this is important, at the place of production. The German company in Russia has factories in Krasnogorsk, Krasnodar Territory, Astrakhan and Chelyabinsk Regions.
In the latter, pink gypsum is mined. Gray is a Krasnogorsk breed. The snow-white mineral is distinguished by a mineral from the Astrakhan region and the Krasnodar Territory. Interestingly, the white and gray mixtures during application can drain, that is, they are excessively plastic.
This gives horizontal waves to the walls. The phenomenon is explained by the granularity of gypsum. At the Krasnogorsk and Chelyabinsk deposits in the rock structure granules of 0.5 mm. In pink deposits of grain from 1 mm.
therefore gypsum plaster "Knauf-Rotband" from the Krasnodar Territory and the Astrakhan Region it is easier to apply, it is better fixed and lay down more evenly. However, the coarse-grained coating on the walls is a plus if it is a finish.
If you need a perfectly smooth surface, for example, under a wallpaper, it is better to be angry over the application of a white or gray mixture. The addition of an additional portion of water to gypsum powder turns it into a plaster slurry.
It is plastic and sticky. The latter property provides the material with good adhesion, that is, the ability to penetrate into the treated surface. In order to fill every click in them, gypsum plaster contains polymer additives. These include latexes, a number of resins.
The adhesion of the rotband allows him to firmly grasp with drywall, concrete, wooden and brick bases. Knauf plaster does not shrink on them, does not crack.
Rothband refers to frost-resistant plasters, surviving 75 cycles and serving excellently on ceilings, in corridors, porches. The only problem is the hygroscopicity of the plaster. Gypsum absorbs moisture not only when mixing the powder, but also during operation.
On the one hand, this allows you to control the indoor climate. Small and temporary excess vapors are absorbed by the coating of walls and ceilings, giving back when the air dries. However, if the humidity is high and constant, the plaster swells, loses its aesthetics, and is affected by fungi.
The hygroscopicity of the rotband affects its shelf life. It is 6 months from the date of packaging. During it, atmospheric air enters the bag with plaster, and with it moisture.
Even an unpacked rotband when used after six months begins to crack on the walls. Finishers are not always to blame, sometimes, you need to check the date of packing of the plaster. By the way, it should be stored packed and in a dry room.
It remains to mention the thermal conductivity of the hero of the article. Finishing material equally poorly conveys both cold and heat. Thermal conductivity is 0.25 watts per meter. In proportion to the index of mineral wool - a classic insulation.
Given that the maximum thickness of applying a rotband is 5 centimeters, plaster can be helpful in warming the room. However, with a minimum layer thickness of 5 millimeters, you don’t have to expect much from the coating.
Rotband application
In a bag of gypsum mixture 30 kg Rothband plaster, as we recall, it is diluted before application with water. The solution is usually mixed with a construction mixer. As a result, about 40 liters of the mixture are obtained from the bag.
To 30 kilograms of powder add 18 liters of cold water. First, 5-7 masters of a rotband are stirred. The rest is poured out with a second walker. Mix to a uniform consistency of cottage cheese with sour cream. After the ripening period, you can mix again.
If you put the plaster in a layer a centimeter thick, about 8.5 kilograms will take per square meter. Rotband Consumption can “swim” at the same floating level of walls and ceilings. Therefore, before applying the mixture, it is customary to level them out as much as possible. It’s on hand and when finishing the room.
Stucco Walls with Rottband requires a 10-minute aging solution after kneading. Time is spent on the so-called maturation of the mixture. After, the solution remains suitable for application in an open container for about half an hour. Accordingly, it is worth kneading the volume that you apply to the treated surfaces during this time.
After application, the centimeter layer dries in about 50 minutes. A full set of strength takes 7 days. The first of them should not be ventilated. During plastering, direct sunlight should be avoided.
Apply rotband band plaster falcon from bottom to top. After, the layer is aligned with the rule, working it in a zigzag. A metal spatula is taken at the initial stage of the solidification of the solution after 45-60 minutes. This is the step of cutting off the excess and filling the recesses in the coating.
Then, they give him another 15 minutes and sprinkle out of water. After, you can grind the surface with a felt grater. Then, bumps are again removed and the matte effect of the coating is expected. This is a signal for grinding with a metal grater.
The rotband is structured, that is, it can play the role of textured plaster. The texture of the coating is given with a stiff brush or embossed roller at the solidification stage.
The pros and cons of a rotband
So, why did the rundband appeal to consumers? Without gypsum plaster repairs can not do. Finishers repeat the word “rotband” so often that consumers who are far from construction remember from dozens of specific concepts of it.
German plaster suits everyone with easy application and lack of tendency to delamination. The ecological compatibility of the mixture also attracts, because gypsum is a natural mineral, devoid of harmful impurities, radiation.
The rotband is low in comparison with competitive mixtures and has excellent crack resistance. An exception, as mentioned, are expired plaster samples. With quality, a perfectly flat and dense surface is achieved.
A dried rotband has 950 kilograms per cubic meter. Such a density indicator is worthy of gypsum stone in its original form. That is, hardening, the mineral crumb is close in properties to the source.
Appreciate the hero of the article for quick drying. Most plasters set and mature longer. However, on a rainbow background there are a couple of minuses. Firstly, gypsum coating has low strength. For cement plasters, it is an order of magnitude higher.
In addition, the rotband is capable of corroding fasteners. Moisture from gypsum is transferred to screws and nails. Without anti-corrosion coating, the fasteners rust. This leads to the formation of yellow spots and smudges on the surface of the plaster.
A disadvantage of the rotband is its low resistance to excessive moisture. The indicator forces you to abandon the hero of the article in saunas, pools, baths, outdoor facilities. Otherwise, Knauf plaster is a popular product. Find out its price. By the way, it also refers to the relative disadvantages of the material.
Rothband price and reviews
The price of stucco rotband starts at 370 rubles per 30 kg bag. There are smaller packings. For a 10-pound package, for example, they ask about 200 rubles.
Most domestic gypsum mixtures, and some foreign ones, are 20-30% cheaper. However, the sales leader is the Knauf mixture. The reason is consumer confidence. Rothband justifies the price with consistent quality.
In support of the above, we give reviews about the hero of the article. Let's start with a comment by Yulia Balashina published on IRecomend.ru: - “We changed the kitchen door. We have a Soviet five-story building.
The door burst out with the root. The jamb was badly damaged. The master suggested restoration with plaster, advising the rotband. I am satisfied with the result. The jamb is smooth, without cracks. The new door sat perfectly. ”
In the reviews, consumers note not only the quality of the rotband, but also attractive promotions from the manufacturer of the plaster. So, on the same IRecomend.ru, a certain Soho Rich writes: - “We bought bags with New Year’s promotion.
There were codes in the packages. Registered them on the Knauf website. After 10 working days we were returned 40 rubles from each bag of plaster purchased. Given its high cost, very nice.
However, and without discounts, we will choose only rotband. My mother also took him for repair, aligned both walls and ceilings. Then the satisfaction from the selected product was no less than the present, albeit without a discount. ”
Finally, we note that the first batch of rotband was released in 1962. Over the 55-year history of the brand, the finishing mixture has never gone into the “shadow”. Perhaps it is a matter of initially verified formula and technology, because the brothers Karl and Alfons Knauf are mining engineers with professional education.
The enterprise remains in the hands of the family that founded it. In Russia, she opened production in 1993. Accordingly, the brand has been present on the domestic market for 24 years. The first in the capital of the brand was TIGI. This is a plant of thermal insulation and gypsum products.
Benefits
- Gypsum plaster KNAUF-Rotband provides a smooth surface that does not need additional puttying.
- Does not crack even with a thick layer.
- KNAUF-Rotband gypsum plaster consumption is 2 times less than traditional cement-sand stucco mixtures.
- Application of plaster coat up to 50 mm thick in one coat without preliminary spraying. If necessary, the application of thicker layers in two.
- The versatility of the material - simultaneous plastering and puttying, the manufacture of decorative elements, repair and restoration work.
- High water retention capacity - the mortar mixture does not exfoliate and does not dehydrate even on porous, moisture-absorbing substrates and at elevated temperatures.
- Regulates the humidity level in the room - the surface “breathes”, creating a favorable microclimate in the room.
- The material is made of environmentally friendly natural mineral (gypsum) and does not contain substances harmful to human health.
Material Features
In order to gain popularity, the material must have positive qualities for the buyer, distinguishing him from goods from other manufacturers. If you look at the technical characteristics of Rothband plaster, it immediately becomes clear what it is most often chosen from. First of all, it is suitable for all rooms in the house with both normal and high humidity.
It can be applied not only to vertical, but also to horizontal surfaces. After plastering Knauf with stucco, the bandages do not need to be puttied, and can immediately cover the working area with finishing finishing material.
Due to its high ductility, Rotband plaster can be applied with a layer of up to five centimeters in thickness, which, as a rule, is sufficient for leveling the surface. Due to this, layering of the material is not required and the time spent at this stage is reduced.
The temperature range for working with this dry mixture is large enough and starts with plus five degrees, and ends with plus thirty degrees Celsius. Given this, you can work with it without difficulty in rooms with varying degrees of heating.
Also attractive is the low consumption of rotband plaster per 1 m2, which is eight and a half kilograms with a layer thickness of one centimeter. The complete drying time of the composition is a week.
Gypsum stucco is sold in 30 kg bags, which are compact enough and convenient for transportation in a personal car.
Plastering
In order to align the walls correctly, you need to know the features of this work and follow the instructions for plastering the rotband.
Before proceeding to the direct plastering of the surface, it is preliminarily prepared. To do this, it must be cleaned and primed. It is good to use a primer from the same manufacturer as the plaster. In this case, they will be perfect for each other.
After the working area is ready, you can proceed to the cultivation of stucco rotband according to the instructions on the pack. In order for the mass to turn out to be homogeneous, it needs to be mixed very carefully with a construction mixer. The presence of lumps is unacceptable.
The application of plaster on the wall surface starts from the bottom up. The minimum layer thickness is half a centimeter. If one layer is not enough to give the surface perfect evenness, you will have to apply the second layer, for which, after drying, the first one is primed and only then the second layer is applied. In this case, the price of repairs using rotband plasters, packaged in 30 kg, will increase.
At the end, the surface must be smoothed. This is done after about an hour after applying the plaster. This part of the work can be completely missed only if the surface was prepared for laying tiles for which roughness of the plaster is not dangerous.
The high price of gypsum plaster Rotband fully pays off with excellent quality, which is already visible in the process.
Specifications
- Consumption when applying a layer of 10 mm:
8.5 kg / m 2
7 days
950 kg / m 3,
Dry plaster mixes can have shades from white to gray and even to pink. This is due to the presence of natural impurities in gypsum.
The color of the mixture does not affect its characteristics.
Basic characteristics of plaster
Knauf specialists keep the exact composition and production technology of the Rotband mixture a secret. Only the components providing the high quality of this building material are well known:
- gypsum powder with additives that improve the absorption of water and prevent shrinkage after application,
- ductility enhancing plasticizers
- fine-crystalline dusty filler, which ensures the resistance of the finished coating to external influences.
For work, it is enough to dilute the mixture with water in the proportions recommended by the instruction and begin applying to the desired surface.
There are many imitations of Rotband plaster in the building materials market. They consist of gypsum, ground sand and acrylic resin, but in quality they are significantly inferior to the original.
Types of plaster
One of the components of the Rotband mixture is natural impurities. They do not affect the quality, but give the material a certain color.
On sale you can find 3 types of plaster:
- gray - production of Krasnogorsk,
- white - “Knauf Gypsum Kuban”,
- pink - “Knauf Gyps Chelyabinsk” and “Knauf Gyps Kolpino”.
White and gray mixtures, when misused, drain and form waves. This is due to the presence of small (0.5 mm) particles in the composition. Pink contains large (up to 1.2 mm) grains, therefore this lack is lacking.
How to calculate the quantity
Plaster consumption per 1 square meter with a layer thickness of 10 mm - 8.5 - 9 kg. Recommended coating thickness for high-quality surface leveling - 15 mm. It follows that for finishing 1 sq / m, 12.7 kg will be needed. An additional 10% should be added to this amount. Total recommended amount is 14 kg. Multiply this figure by the total area of the processed surface.
On the Internet you can find special calculators of the flow rate of the Rotband mixture. They give accurate numbers of material when you enter the room area and the planned layer thickness.
Step-by-step application guide
To work on the plastering of surfaces went quickly and efficiently, it is necessary to prepare the following set of materials and tools:
- cement-sand mixture
- primer,
- primer roller,
- container for mixing plaster,
- drill with a nozzle,
- putty knife,
- the rule
- building level,
- beacon profiles
- trowel,
- scraper and grater.
- reinforcing mesh (for applying a layer of more than 2 cm.).
The plastering process consists of several stages. Each of them must be carried out, following the recommendations of specialists.
Preparatory Activities
For reliable adhesion of the solution to the surface, it must be pre-treated:
- Clean old coating. Wash oil stains with a degreasing solution.
- Remove the tubercles with a puncher or spatula. Seal deep cavities with cement mortar, shallow cavities with putty.
- If the base is smooth, make notches for better adhesion to the mortar.
- Primer the surface in 2 layers and dry for at least 24 hours.
- If necessary, fix the reinforcing mesh.
- Install metal beacon profiles. They are mounted on the wall with a plaster mixture and leveled. The distance between the beacons is 3⁄4 of the length of the rule.
Solution preparation
For 30 kg of the mixture, 18 liters of liquid will be needed.
When mixing, it is worth observing a certain sequence:
- A third of the volume of water is poured into the container.
- Throw 6 to 7 powder trowels and mix.
- Then the remainder of the water is poured and the remaining amount of the dry mixture is poured.
- Drill or manually mix the solution to a thick sour cream. The process is not stopped until all lumps disappear.
- After reaching the desired density leave a solution for "ripening".
The amount of the finished solution is calculated so that it is applied to the surface within 30 minutes. The next batch is prepared after the first one is fully consumed. It is impossible to dilute the finished mixture with water when it partially hardens. This will degrade the performance of the solution.
The plaster dries quickly on the tool, so after using each portion it needs to be washed.
How to apply plaster
The quality of the material allows you to get a great result, even for a beginner. The layman will spend more time, but if you follow the instructions and accuracy, he will completely cope with the work.
Sequencing:
- Spread the finished solution with a thickness of 5 to 10 cm onto the surface. Place it in rows, from bottom to top.
- As a rule, stretch the solution from the bottom up, while aligning it with beacons. The tool is pressed to the surface of the lighthouses and moved in zigzag movements. They make several passes, each time clearing the excess solution from the rule and filling in the resulting gaps.
- Rothband plaster is very plastic, so the coated surface must be corrected during the setting process.
- Approximately 10 to 15 minutes after the initial application, the solution ceases to float, and it begins to be leveled with a wide trowel or finishing rule.
- After 30 - 40 minutes, the main layer of plaster sets completely and the surface is finally treated with a grater or fine-grained sandpaper.
- If work is carried out on a surface with large differences, application in 2 layers will be required. The first is combed with a building comb and waiting to dry. Then primed and applied a second layer.
Professional Tips
To get the perfect result when organizing work with Rothband plaster it is worth using the recommendations of experienced craftsmen-finishers:
The dry mixture must not be filled with water. This cooking method will lead to the formation of insoluble lumps, and a portion of the material will be spoiled.
- For additional polishing of the surface, you can apply the method of wet grout. To do this, the wall is slightly sprayed with water from the spray gun and treated with a rigid sponge in circular motions. This will give the surface a spectacular gloss and will immediately apply paint.
- If it is planned to glue light wallpaper on the wall later, it is necessary to additionally cover the plaster with white putty.
- The surface of the plastered Rothband can be given a relief structure. To do this, after the passage, as a rule, the solution is allowed to dry slightly for 10-15 minutes, and then pass with a relief roller or brush with hard bristles.
How to store plaster
The manufacturer sets a period of 6 months for the material in unopened packaging. But if unopened bags are placed in a dry, warm room, the period increases to 1 year. Storage of the mixture at high humidity is not permissible, since the gypsum included in its composition is extremely hygroscopic. If the bag is already open, the remainder of the mixture must be poured into a tightly closed, moisture-proof container.
Universal Rotband plaster is an excellent material for interior decoration of residential and office premises. An important factor in favor of her choice is the high quality of the coating and the possibility of independent work.
