Knauf Rotband Plaster: Gypsum Plaster Mix In Packages Of 30 Kg, Technical Characteristics

2024 Author: Beatrice Philips | [email protected]. Last modified: 2024-01-18 12:09

Knauf Rotband plaster occupies a leading position in many ratings of building materials. The manufacturer's secret is simple: high-quality products, excellent technical characteristics, simple and understandable application even for beginners.

Peculiarities

Knauf plaster is purchased and praised for many reasons. The identity of the concepts "Knauf products" and "famous German quality" need not even be mentioned. This thesis has long been proven in practice. But it should be said that the founders of the company, the Knauf brothers, are mining engineers by profession.

Choosing gypsum as the basis for their building materials, they based on their professional knowledge. Gypsum allows you to make construction of higher quality, faster and more economical, therefore it is the main component in Knauf building mixtures.

All the manufacturer's products are thoughtful, harmonious in composition, effective and affordable building materials. They are produced taking into account the accumulated experience and the use of innovative technologies, pass quality control, are distinguished by their reliability and energy efficiency. A bonus for aesthetes is a laconic and beautiful design of containers and packaging.

Products of the Rothband brand stand out in a separate line. It is a multi-functional mixture of dry components on a gypsum base, which is complemented by three more products from the line: filler for applying the thinnest possible layer and decorative materials "Rothband Finish" and "Rothband Profi " … The latter is produced in the form of a ready-made pasty mass.

Features of Rothband plaster:

• Multitasking. In fact, this is a universal tool for preparing a rough surface for decorative finishing and the decoration itself. She can fill up cracks, irregularities and chips, level the surface of the walls, create decorative elements. It even increases adhesion between the work surface of a wall or ceiling and the finishing material. Therefore, if a beginner, who first took up repairs with his own hands, suddenly forgot to apply a primer to the wall, the Rotband plaster will replace it.
• Excellent quality.

• Suitable for professional decoration and private use;
• Compatibility with finishing materials from other manufacturers and within the line of the same name.
• The ability to use plaster on different types of surfaces: wood, concrete, brick, old walls, secondary housing (re-finishing), drywall, concrete, cement, block materials, cement plaster, expanded polystyrene, OSB and CBPB.
• Materials are adapted for the climatic conditions of our country;
• It can be used for rooms with dry microclimate, in conditions of moderate humidity and in rooms with high humidity with additional protection.

Experienced professionals know that quality plaster is the key to successful interior decoration and renovation.

The list of benefits of the Rothband blend is quite compelling:

• When using it, you will not need an additional layer of putty. This significantly saves time and money and simplifies repair work.
• The plaster layer can be applied in any desired thickness. It will not crack from uneven drying or its own weight.
• Due to the fact that the mixture is based on gypsum, universal for finishing works, the consumption of materials is reduced. In comparison with cement-sand mixtures, it is almost two times less.
• It is possible to apply up to 50 millimeters of the mixture in one go!
• Thickening of the plaster layer increases thermal insulation and sound insulation in the room.

• The versatility of the material in all respects: in terms of compatibility with different surfaces and functional use. Knauf "Rotband" plaster is suitable for rough, decorative and restoration work.
• The setting rate of gypsum is much higher than that of cement mixtures, so you can start finishing work earlier.
• The mixture is plastic, it is convenient to use it in hard-to-reach and embossed places.
• Knauf "Rotband" provides a fire resistant finish.
• Thanks to the unique components of the composition, the plaster mixture is able to retain moisture in itself, even when used on absorbent and porous surfaces. This allows it to remain intact, without cracks and irregularities during and after drying.

• The surface of the walls is breathable, condensation and greenhouse effect are not formed.
• Gypsum is a pure natural mineral that does not pose any threat to the human body. It is non-allergenic and contains no toxins. In addition to fine gypsum powder, the composition includes components that increase adhesion and prevent shrinkage, plasticizers necessary for the fluidity of the mass and its hardness after solidification, fine-crystalline silicon oxide. For breeding, ordinary water is used.
• The color of the plaster is basic, suitable for any kind of decorative work, and the texture has good adhesion. This allows the use of a minimum amount of primer before applying the decorative coat.

The mixture has some disadvantages noted by experts:

• when filling deep cracks, the material may shrink slightly;
• the second layer of plaster is poorly applied over the first; the use of primers is required;
• the material consumption in practice turns out to be slightly more than indicated by the manufacturer on the packaging;
• the mixture quickly hardens in air, so the finishing must be done promptly;
• the price for 10 kg of the mixture is two times higher than the price for the products of a domestic manufacturer, and one and a half for the products of other foreign manufacturers.

Specifications

Technical characteristics of Knauf "Rotband" plaster are a combination of material properties, features of its application on different surfaces and performance properties. They include a number of indicators such as composition, color, thickness, shelf life, drying time, and others.

Release form

Dry plaster mix is produced in a standard bag format from 5 to 30 kilograms. Five-kilogram bags are made of plastic and paper. Weights 10, 25 and 30 kg are available in paper bags only. The finished finish (paste) is produced in a plastic container with a volume of 5-25 liters.

The Knauf "Rotband" line has several anti-counterfeiting features that make it easy to distinguish quality products from clandestine material from unknown raw materials.

These include:

• stylized round stamp “German standard. Tested quality ";
• time and date marking of production accurate to seconds;
• embossing in the form of stripes on the top layer of the packaging made of special paper.

In cases of doubt about the authenticity of the material, you should apply for a quality certificate or directly to the company's employees, who will identify non-advertised ways of protecting against counterfeiting.

Terms and conditions of storage

The mixture is suitable for use within six months if stored in a dry ventilated room at a temperature of 5-25 degrees, away from sources of heat, humidity and direct sunlight.

Compound

The composition of the substance is universal and is not disclosed by the manufacturer in order to avoid counterfeiting. It is known that this is a finely dispersed gypsum mixture with the addition of components of mineral origin that increase the elasticity, strength, ability to retain moisture and adhesion of the substance and minimize its shrinkage and cracking.

Classic plaster is white both in dry form and after drying on the surface of walls or ceilings, but sometimes there is a coloring pigment in the composition.

Colour

The color of the plaster is chosen according to the type and shade of the decorative material. It is insignificant, but it still affects the performance of the material and its "behavior" during finishing work.

There are three tinting options available: white (can also be called colorless due to the lack of coloring pigment), gray and pink … According to the manufacturer, the color is not chosen specifically, but depends on some impurities in the mineral rock. It does not affect the quality of the coating in any way.

White plaster is considered "classics of the genre".

Produced both at factories in Germany and at branches of the Krasnodar Territory and the Astrakhan Region. The gray mixture is produced in Krasnogorsk. Pink is produced in the town of Kolpino, Chelyabinsk region. This division into regions is explained by the location of the quarries in which the raw materials for the production of mixtures are mined.

Fraction size

This parameter is also subject to standardization. The manufacturer does not set the minimum indicator, but the maximum is 1.2 mm.

Fine-grained plaster can give a "flow" effect on a vertical surface … As a result, streaks form on the wall, which must be removed. It is recommended to use it under dense finishing materials, for example, some wallpapers.

With a coarse-grained mixture, such problems do not arise. It is suitable for self-decoration.

Thickness

The minimum and maximum values of the layer thickness for different surfaces vary within different limits. For walls, the manufacturer recommends starting one layer with 5 millimeters and not exceeding 50, for the ceiling the lower indicator is the same - 5 mm, but the upper one is several times less - only 15 mm.

Surfaces that need to be processed with a layer of more than 50 mm in thickness are plastered in stages. First, a primer is applied (preferably from the same manufacturer), then a layer of Rotband putty, and after it dries, the surface is re-primed. When the primer is dry, you can apply a second layer of plaster up to 15-50 mm thick.

Drying time

The time frames for each state and process are different:

• "Maturation" of the solution after adding liquid to the mixture lasts 10 minutes;
• the solution retains the consistency of a liquid mass in an open container for half an hour;
• drying of a layer of minimum thickness is several hours, depending on the microclimate in the room;
• drying of a full layer is 7 days. Some sources mention shorter periods (24 hours, 3 days), but the manufacturer's official recommendation is to start finishing no earlier than a week later.

The dry mixture has a density of 730 kilograms per cubic meter, the hardened plaster is slightly more - 950 kg / m3

Strength

It is referred to as "compressive strength" and "flexural strength", which means the resistance of the plaster layer to pressure, so that the integrity is not damaged.

The maximum allowable pressure on a layer of Rotband plaster in compression is 2.5 MPa, at the bend - above 1 MPa. It is difficult to measure such indicators on your own, so it is important to just check the information on the package. The numbers for these items should not be lower than 2, 5 and 1.

Adhesion

Knauf Rotband is a versatile plaster that adheres best to even concrete and cement surfaces, but also copes with porous and uneven walls and ceilings.

Sustainability

This means resistance to temperature extremes, low temperatures, humidity, fire resistance. The manufacturer does not indicate such data in the information on the packaging, but it has been experimentally found that the material can be used in rooms with a humid microclimate (bathrooms, kitchens), it has vapor permeability, moisture resistance, and fire resistance.

Consumption

A rare manufacturer of building materials is not cunning, indicating on the packaging the approximate figures for the consumption of the substance per square meter of the treated surface. Even Knauf, with its impeccable reputation, does not give 100% correct information.

When calculating, you should always take into account that in practice it may take a little more mixture to treat problem areas ., a layer thicker than planned will turn out or part of the plaster will be damaged due to improper storage of the finished mixture.

There are two ways to determine the consumption per square meter:

• take the figure indicated by the manufacturer on the packaging (for Rotband it is 8.5 kg per square meter with a layer thickness of 1 cm), multiply by the entire area of the treated surface of the walls or ceiling and round the number of bags upwards for insurance;
• independently calculate the average layer thickness and the amount of material. Self-counting is time consuming, but more accurate. A 1 cm layer of plaster is not always enough. This is due to the fact that the surface of the walls or ceiling is not perfectly flat due to defects in building materials. Height differences are inevitable.

To level them and calculate the correct number of bags (kilograms) of plaster, you need to follow the sequence of actions:

"Hang" the wall at three points and determine the average layer thickness. For hanging walls, so-called vertical beacons are used. To install them, you need nails and plumb cords. Lighthouses are installed every 3 meters. With their help, deviations along the vertical and horizontal lines are calculated. For example, if on a wall with an area of 9 squares deviations are 3, 4 and 5 cm, their total number is divided by the number of beacons, the result is an arithmetic mean equal to the required thickness of the plaster layer. In this case, it would take 4 cm

• Review the manufacturer's recommendations. Knauf recommends sticking to a ratio of 8.5 kg per square.
• Calculate the required amount of plaster. To do this, the manufacturer's rate of 1 cm is multiplied by the thickness of the middle layer, and then the resulting figure kg / m2 is multiplied by the entire area of the working surface.
• Since the products are sold in packages from 5 to 30 kg, you need to divide the resulting figure by 5, 10, 25 or 30 in order to calculate the number of bags of this volume required to repair one room.
• Calculate a small stock. The weight of the plaster for the entire surface area is taken as 100%, you need to find how much in kilograms 5-15% of this weight will be. The resulting figure varies depending on the volume of the bag. For example, if 10% was 6 kg, it is wiser to purchase a 5 kg bag for insurance than 25, overpaying for it several times.

Application area

Plaster is used for interior and exterior decoration of buildings for various purposes.

First of all, it is necessary for leveling the walls of the premises, both from the inside and outside (the types of plaster are different in this case). The construction of houses in the 90s and massive modern buildings can hardly be called high quality. There are deep cracks, cracks, depressions and irregularities between the fragments of the walls, ceiling and at the joints of vertical and horizontal planes. All this greatly interferes with the decorative finish.

The use of plaster greatly simplifies and speeds up the repair … On the one hand, because the work surface becomes even, on the other, because the rough surface of plastered walls and ceilings becomes an ideal base for priming and adhesion of decorative materials to it.

Another problem with surfaces with defects is significant heat loss. Through all the gaps in the walls and ceiling, warm air leaves the room, so the temperature in the house is lower than we would like, and part of the financial costs for heating literally flows out into the street.

Together with an increase in thermal insulation in the house, plaster (especially in several layers of 50 mm) helps to improve sound insulation

In humid rooms, it performs a sanitary and protective function, reducing the negative impact of a humid microclimate on the surface of the walls and ceiling. It is also applied to the outside of the building for protection. This increases resistance to weathering and improves insulation performance.

Also, plaster is necessary for processing thin brickwork and drywall partitions when redeveloping indoors.

Finally, it has a decorative function. The potential of gypsum plaster in this regard is very great, because with its help, you can create smooth and textured coatings, imitation of stucco molding and volumetric elements on the wall and ceiling … The consistency of the plaster is convenient for artistic modeling, and the relief pattern is completely created by simply rolling it on wet plaster with a stencil roller.

A secret from professionals: if you add color to the plaster mix, and not only paint the top layer, chips on the surface of the walls, in the corners, on embossed areas will be almost invisible.

As a rule, each type of work requires its own type of plaster. The advantage of Knauf "Rotband" is that it is versatile and suitable both for leveling walls before wallpapering and for restoration work.

Recommendations for puttying

As professional painters joke: rely on the manufacturer, but do not make a mistake yourself. Good quality plaster does not guarantee a perfect result by itself. It is important to apply it correctly, only then the result will be optimal.

The work is carried out in stages, starting with preparation and ending with the application of protection to decorative plaster.

Preparatory work

The basis for applying plaster can be in different states. In the first case, these are walls in a new building that have never undergone cosmetic repairs, in the second, walls that are undergoing repairs again or old walls.

The processing of new surfaces is easier, the set of tools at hand is minimal.

It is necessary to remove construction debris from the premises, if any, dust the ceiling, walls and floor, protect all surfaces that will not be subject to painting, treat the base with a primer in two layers with a break of 24 hours

For maximum effectiveness of Knauf "Rotband" plaster, it is recommended to use a primer from the same manufacturer.

Slightly harder to prepare "secondary" surfaces … The list of necessary tools is already impressive: spatulas, scrapers and cord brushes, tools for removing an old layer of plaster and putty (hammer, chisel), a special solution for dissolving and removing enamel, lime, plaster or other finishing materials, brushes or rollers for applying a primer, cleaning wipes and containers with water, protective equipment (gloves, respirator, when working with the ceiling - glasses).

First, you need to remove the old coating from the wall or ceiling. Wallpaper can be wetted and removed with a spatula, paint remover B52 can handle enamels and different types of paint, bulk materials can be removed with metal cord brushes and sanded with coarse-grained sandpaper.

After cleaning the surfaces, the room is dedusted with a dry and wet method, Knauf primer is applied to the ceiling and / or walls. After a few hours, you can apply a second layer and wait a day, then start applying the plaster.

The preparatory stage also includes the organization of a suitable indoor climate. Work should be carried out at a temperature not lower than +5 and not higher than +25 in a room without drafts and dampness.

Mixing the solution

Since Knauf "Rotband" plaster is sold as a dry mix, you need to prepare it yourself before applying it. To do this, you will need: a container with water, a container for mixing the solution (bucket, basin, paint bath), scales and a measuring jug for batch mixing, a drill with a mixing attachment or a construction mixer to create a homogeneous mass.

Professional painters recommend pouring the dry mixture into a container with water, and not pouring it in, and use 9 tenths of that amount , which is indicated by the manufacturer in a liter / kilogram ratio. A mixture that is too thick can be diluted with water, but it is already more difficult to mix dry matter into the finished solution ..

The mixture is poured into water, mixed with a construction mixer for 2-3 minutes, then allowed to brew. The ripening time of the solution is up to 10 minutes. It hardens quickly in the open air, so you need to cook it in small quantities and cover the container with wet plastic.

With improper preparation of the surface and mortar, the following defects are possible:

• Cracking of the plaster layer … Cracks appear during the shrinkage process due to too rapid evaporation of moisture. Knauf "Rotband" contains special moisture-retaining components, but this does not negate the fact that the fresh plaster layer must be looked after, and the solution must be prepared according to the recommendation of professionals.
• The appearance of bumps … This is the fault of the lumps in the solution, which remain if it is not stirred thoroughly enough.
• Flaking … It occurs when plaster is applied to a dusty, greasy, unprepared surface.
• Bloating … This is a common occurrence in damp rooms. Therefore, when working, for example, in a bathroom, professional painters recommend that you first dry the room, and then proceed with finishing.
• Rough surface … This is the result of poor grouting and neglect of the pruning procedure.

Application

To carry out painting work, you will need a set of tools: a painting bath for pouring a small amount of solution to handle difficult areas, a stepladder for processing the upper edge of the surface, a trowel - a tool for mixing, applying and leveling the plaster mass. Also, for application, a half-trowel and an aluminum rule can be used. As a rule, plaster is applied to the corners and the uniformity of the layer distribution is checked.

According to the "classics" of painting skills, the application technology includes 3 stages, sometimes they are preceded by the repair of large cracks and defects.

For cracks, the solution is diluted separately, in a small amount. Then they need to be expanded, blown out, cleaned of debris and covered with plaster. If the crack is deep, a folded mesh is preliminarily inserted into it, and then sealed.

You can proceed to the main part:

The first stage is spraying . It involves applying a fresh plaster mortar in a thin layer of 5-6 millimeters to the primed surface. It is more convenient to apply the solution with a trowel, and then level it with a half-trowel or a rule, while eliminating irregularities. The layer should dry well.

The second stage is the soil . If the surface of the wall is relatively flat, this stage can be completed by applying a layer of the required thickness to the wall. For old crumbling walls that require reinforcement, use a paint net. It is placed directly into the wet soil layer and then covered with a third layer.

The third stage is “covering” . It should be as even as possible. It is used to smooth out defects in the primer and is not always applied to the entire surface of the wall. In some cases, only those areas where there are still differences in thickness are treated with it. Before the next step, the layer should set and dry a little.

On walls without any special defects, it is enough to apply plaster in one layer with a thickness of 5 to 50 mm.

Knauf "Rotband" plaster is often used on problem areas that are difficult to level with a centimeter layer. As a rule, these are walls with a large curvature or in an old house with obvious defects. In this case, the list of tools is replenished with aluminum profiles, from which beacons are prepared (guides for leveling the wall).

The procedure is as follows:

• Determine the curvature of the wall and the required thickness of the leveling layer using a level or rule.
• Make a plaster mortar and use it to "stick" the hillocks on the wall with a step of 30 cm vertically. Horizontally, beacons are placed every 1-3 meters.
• On the tubercles, aluminum beacons are fixed with plaster mortar. Do not be zealous, after applying the leveling layer, they will need to be removed, and the gaps from them should be repaired.
• The reference point for leveling the plane along the horizon line is a lace stretched between the lighthouses.
• Further, the plaster is applied over the beacons in one or two layers up to 50 mm thick.

Pruning

This step is often overlooked, and meanwhile, it simplifies the process of subsequent grouting. Pruning is carried out 30-40 minutes after application the last (or only) layer, when the plaster has already set, but has not yet completely hardened.

In order to remove excess and fill in irregularities, a trapezoidal aluminum rule with a sharp edge is used. It “cuts off” everything unnecessary and transfers it to other areas or completely removes it from the surface.

With neat work, trimming is not required, but for those who do the work with their own hands for the first time or do not have much experience, it will be useful.

Grout

It is made on the set, but not hardened, top layer of gypsum. To do this, the painter's float is pressed against the wall and the plaster begins to “rub” the plaster in a circular motion until it becomes even and smooth.

Gloss

This painting trick allows you to avoid using putty on top of the plaster. The polishing procedure consists in the fact that 3-4 hours after grouting, the plaster surface is abundantly wetted with water from a spray bottle and processed with a metal trowel. After this procedure, the wall is completely ready for applying a primer and decorative coating.

But not always paint, wallpaper or other materials are used on top of the plaster. Knauf "Rotband" plaster itself is already suitable for wall decoration.

Decoration

The use of a universal gypsum plaster from the Rotband series for finishing walls has several advantages:

• saving time, finances and effort for finishing, since one material solves several problems at once;
• spoil the surface, which should be embossed, is daunting. The technology is relevant for beginners who are afraid to do the decoration with their own hands;
• the decorative coating will be reliable, beautiful and durable;
• gypsum mass is malleable and easy to process, so with its help it will be possible to create an interesting design or unusual wall decoration.

Two common techniques for decorating walls (or ceilings) with plaster are to give it a relief or a bright shade.

They paint the plaster in different ways. The result is a washable, beautiful surface and a durable finish.

It can be monochromatic, with a stencil or freehand drawing, multi-colored (for example, it is important to use several different colors on opposite walls to visually change the parameters of a room), with imitation of wood, stone, aged materials, with a mother-of-pearl effect.

Working with texture is more varied. You can add relief to the plaster with the help of professional and improvised tools:

• Foam rollers and coarse nap rollers … The drawing is obtained in an elementary way - the rollers are rolled over wet plaster with slight pressure. The texture is peculiar, it easily masks application defects.
• Special stencil rollers … They are rigid with convex or, on the contrary, in-depth ornamentation. You need to roll them along the wall carefully so that the drawing does not move out, since usually it is a repeating and quite specific figures: a herringbone, stripes, flowers and other patterns.

• Stamps … This is a painting tool, on the surface of which there is a convex or in-depth pattern. It is applied and lightly pressed into the wet plaster to transfer the pattern to the wall surface. After each application of the stamp to the wall, it must be cleaned with water so that the drawing remains clear.
• Painting tools: spatulas, trowel, brushes, graters … They apply the drawing by hand according to certain schemes or chaotically. You can get the structure of the stone, imitation of decorative plaster "bark beetle" or "rain" without overpayment for finishing material. Using a hard-bristled brush, draw circles, semicircles, wavy lines and any other patterns.

• Brush or broom … The technology of their use resembles a child's trick in drawing lessons, when paint is scattered over a sheet of paper with a toothbrush. You need to dip the fleecy part of the brush or broom into the liquid gypsum solution "Rotband" and run your hand over the elastic pile towards yourself or knock the plaster from the broom onto the wall. It turns out the effect of "splashing" the wall and the embossed pattern.
• Protective polyethylene film … Its dimensions should be one and a half to two times larger than the wall area so that it is possible to form folds and a pattern, and its density should be average. Too thin film will not "capture" the plaster, and too dense will not give the desired effect of "shamming".

The film is applied to the wall from left to right, gluing it to the wet surface of the plaster and at the same time forming folds and creases. It is more convenient to do the work together so that the free edge does not adhere arbitrarily and the plaster does not have time to dry.

Another option for using the film is to “blot” wet plaster with it. A small piece of film should be crumpled in your hands and walked over the entire wall with "prints", pressing it for a few seconds to the surface of the wet plaster.

To complete the painting work, it is recommended to cover the plaster with Knauf protective topcoat or acrylic varnish. It will be easier to clean and less prone to scratches and damage.

Reviews

The overwhelming majority of reviews about Knauf "Rotband" plaster are positive or laudatory. Beginners and non-professionals note that it is easy to work with the material, it can be applied in a thick layer, and the gypsum mass itself does not flow down the wall in the process.

Professional opinion is more specific. Painters recognize that this is a quality product at an affordable price. Plasticity, good adhesion, consistency convenient for application are especially noted. An indisputable advantage is that the mixture dries quickly enough, forming a flat surface for subsequent decorative finishing.

Among the shortcomings, experts note a slight shrinkage of the material. This must be taken into account when calculating the consumption of Rotband plaster and dilution of the solution.