In winter, the floor should be warm, in summer, on the contrary, in addition, it should not creak, or amplify percussion sounds and prevent the penetration of air sounds.
Of course, the surface should be straight without flaws, otherwise the finish - laminate, parquet, etc., will be almost impossible to put. The issue of longevity is just as relevant.
It is the bulk floor that can provide maximum comfort, taking into account all of the above parameters. Dry screed does not interfere with the main finishing cycle.
After the installation of the dry floor is completed, all other work is immediately resumed. The simple composition of the prefabricated base gives clarity and inspires confidence in the environmental friendliness of the materials used.
1. Expanded clay - (in Greek - burnt clay) which forms the basis of the bulk floor, has excellent technical characteristics. It became widespread just because of these factors.
Being an environmentally friendly building material expanded clay:
- environmentally friendly bulk insulation,
- does not contain harmful impurities,
- acid resistant, chemically inert,
2. Gypsum - GVL sheets
Another component of the prefabricated floor is gypsum plasterboard, (gypsum fiber) is made from gypsum (from the ancient Greek. Gypsos - "white clay") - a mineral substance of calcium sulfate - a natural, natural building material, which without exaggeration can be called one of the oldest on earth .
Gypsum is also considered environmentally friendly building material. Thus, bulk floors based on expanded clay, and GVL can be classified with confidence as environmentally friendly floors.
The advantages of the Bulk floor (or dry screed):
1. Lack of moisture. The absence of wet processes is one of the main advantages of this type of screed, which means that the drying process is excluded, which is important.
2. Light weight. A dry screed is lightweight, compared to a monolithic screed made of cement-sand mixture, the weight of the bulk floor can be neglected, it makes the floors too slightly.
3. The strength of the structure. With a detailed analysis of the installation process of bulk floors, there is a feeling that the structure will not be strong, in the future the floor will “fail”, that this technology is not durable. This feeling is deceptive. Expanded clay is afraid of a point load, and the distributed load in the form of GVLV sheets over the entire area gives the base evenness and strength. The interaction of expanded clay fractions of different sizes during leveling eliminates the formation of voids in the leveling layer and when creating a hard base, expanded clay simply has nowhere to go.
4. Short laying time. An additional advantage is the short time of laying the bulk floor, since it does not take time to grind and harden the surface. Flooring can be done immediately after laying gypsum boards.
5. Practicality. The bulk floor is very convenient if you need to "hide" power and low-voltage communications, electric and telephone cables, LAN and Internet lines, fiber-optic systems and even heating and water, which makes dry screed a convenient solution not only for residential premises, but also for office areas.
6. Noise isolation. According to the characteristics of sound insulation, a dry screed also surpasses the usual floors.
Features
Dry screed “Knauf” is quite common among consumers. Features, reviews, the layout of this system will be covered in the article. These floors are easy-to-install, non-vandalized dry-assembled structures that are most commonly used in residential and public buildings. The need for the arrangement of this system may arise when it is not possible to carry out wet finishing processes. These designs are relevant for a large rise in the floor level, as well as for increased requirements for sound insulation of the floor.
If the terms of work are limited, it is best to use a dry Knauf screed. It is possible to carry out work on wooden and concrete floors, but before that it is important to check that the room corresponds to the normal humidity regime, has no restrictions on fire resistance and number of storeys, as well as climatic and engineering-geological conditions. Aggressive substances are not allowed, and mechanical stresses should be characterized by weak intensity.
Dry screed “Knauf”, negative reviews about which may force you to abandon it, can be arranged in rooms with high humidity, such as bathrooms and showers. But at the same time, the correct waterproofing system must be present. At the junction of the floor with the walls, it is necessary to lay a waterproofing tape of the same manufacturer, while the entire surface is covered with waterproofing.
Styling technology
Reviews of the “Knauf” dry screed for the floor can help the consumer make the right choice. So, if we consider the prefabricated foundations of the floors, which are equipped using the Knauf technology, they can be divided into the following types: Alpha, Beta, Vega and Gamma. The first type is a structure laid on even floors. The second is a system on a substrate of porous-fibrous insulation materials, which should be laid on even floors. “Vega” is a substrate-based structure that is represented by a leveling layer of dry backfill. The last variety is the construction of a combined substrate of heat and sound insulating fibrous materials, which are laid on the leveling layer of the backfill.
Pros
The main distinguishing feature of the dry screed method is the lack of so-called “wet work”. The resulting base does not require time to dry, as in the case of a classic screed with concrete mortar. This fact can be attributed to obvious advantages, allowing to reduce the time required for repairs, and to maintain cleanliness in the room.
Due to the absence of "wet work", this method allows you to level the surface of old wooden floors, without requiring their dismantling.
Another advantage of the owners of the premises is the possibility of easy dismantling of the screed covering, if necessary, access to floors or built-in communications and elements of the underfloor heating system.
If with a concrete screed in these cases it would be necessary to break the coating, then in the case of using the dry screed method, the work is done by opening gypsum fiber sheets and removing expanded clay.
In parallel with the leveling of the floor there is an increase in its soundproofing qualities, since the fine-grained expanded clay used for dry screed is an excellent noise absorber.
When only a layer of expanded clay with a size of 6 cm is poured, noise is absorbed within 60 dB, the noise insulation efficiency is enhanced by sheets of gypsum fiber on the expanded clay surface.
The next plus - carrying out a dry screed allows you to insulate the floors even if they do not have a heating system. This effect is achieved due to the heat-insulating qualities of expanded clay and gypsum fiber sheets.
Since work on Knauf Superpol technology does not provide for the fixation of beacons inside the backfill, such floors settle more evenly without creating pressure zones around the perimeter of the beacons.
Another significant advantage is the not too heavy weight of materials required for leveling floors using the Knauf dry screed technology, which floor ceilings in old buildings can withstand. And using this method you can level out any differences in the height of the base of the floors.
Minuses
The main disadvantage of Knauf dry screed is its vulnerability to moisture. This point is associated with the use of gypsum sheets as the main structural element.
One of the characteristics of GVL is the swelling upon ingress of moisture. Therefore, it is believed that in the kitchen, for bathrooms and basements, using a dry floor screed is irrational.
However, to date, the manufacturer has developed a moisture-resistant GVL, which is called "Knauf-Superpol." A similar innovation is recommended for use in showers and unheated rooms, as well as in those where the air temperature drops below +10 degrees.
In all rooms without exception, for maximum system durability, it is required to strictly follow the manufacturer's instructions and apply steam and waterproofing. In those situations where leaks still could not be avoided, it is imperative to open the floor and thoroughly dry all the layers of the screed, if necessary, replace the GVL sheets.
One of the significant minuses, users consider the fact that the drywall laid as a rough floor cracks during operation, falls through under heavy furniture and women's heels.
To avoid this effect, the manufacturer recommends refusing to lay drywall sheets as the top layer of a dry screed. To do this, it is worth using exclusively gypsum fiber (GVL), which will be slightly more expensive, but will last longer and will not cause such complaints.
The disadvantages include the fact that the dry floor system is able to reduce the height of the room by a decent distance, from 5 cm to 12 cm.It should also be remembered that dry floors can only be effectively used in domestic type rooms and are not designed for objects with high traffic.
Cons “high floor” of Knauf consumers call a high price. Among the inconveniences of laying work, builders also mention the large dustiness of the room, which is associated with the expanded clay features, the need to cut GVL sheets, which requires the use of respirators.
"Alpha"
This is an option in which, without preliminary isolation, two layers of GVL sheets (superfloor element) are pointed out on even floor slabs.
With this option, first put on the floor:
- sound insulation layer
- on top are two layers of GVL sheets.
Leveling option, in which:
- expanded clay is poured, allowing to smooth out irregularities,
- on top of expanded clay lay two layers of GVL.
"Gamma"
Sound leveling option in which:
- expanded clay filling is done,
- expanded clay is covered with a layer of waterproofing,
- soundproofing material
- everything is closed by two layers of GVL.
Most often, the Vega option is used as the most economical and providing the least load on the ceiling.
Training
The installation of a dry screed requires the presence of specific equipment and the presence of experience among performers. This is especially true for leveling work.
One of the most important points is the determination of the maximum level of floor rise, since deviations from the horizontal can reach significant values in different corners of the room.
For the most accurate assessment, use the laser level. This equipment is very expensive, so in cases where the owner of the building has construction skills and wants to level the floors on his own, it would be wise to rent a laser level for a couple of days.
You will also have to rent such a specific tool as the special Knauf Alu-Abziehlatte profile and the expanded clay rule manufactured by Knauf, which consists of a metal strip resting on guides.
A feature of the Knauf Alu-Abziehlatte profile is that it allows you to level the surface without putting anything under it. Also, it can be quite simply removed from under the layer of aligned expanded clay, without disturbing the smooth surface.
The following tools are needed:
- a screwdriver - it will be needed to fix the GVL sheets to each other,
- jigsaw, or jigsaw - required for cutting gypsum fiber,
- shovel - will be needed to fill expanded clay,
- knife - will be needed to cut the waterproofing film.
A vacuum cleaner will also be useful, which will be convenient to collect the dust remaining after cutting the gypsum fiber.
Materials required for laying dry screed (Vega variety):
- vapor barrier film
- expanded clay small fraction (it is desirable to use original material from Knauf),
- damping tape
- GVL sheets (prefabricated superfloor element),
- self-tapping screws for GVL (length 19 mm),
- glue for gvl,
- putty.
An important point is the calculation of the consumption of expanded clay mixture, which will be required in each case. The minimum thickness that can be backfilled is 2 cm.
Backfill calculation is carried out using a laser level, a ruler and a calculator:
- we mark the room into 1sq squares. m / 1 sq. m
- set the level of the same floor height and mark it on the adjacent walls,
- measure the height of the backfill with a centimeter for each square,
- by the addition method we determine the volume of backfill required for the entire floor,
- since there are 40 liters of material in one expanded clay bag, we divide the resulting volume by 40 and get the required number of backfill bags.
The calculation of the number of GVL sheets, vapor insulating film and damper tape can be done directly in the store, informing the sales assistant about the size of the room.
Preliminary preparation of the base consists in sealing serious gaps and cracks.
Styling technology
It is best to entrust the Knauf process of laying dry floors to trusted professionals who give a guarantee for their work for at least 6 months. If it is not possible to find such masters, it makes sense to try to master this type of work yourself, carefully and responsibly approaching the process.
Stages of installation of dry screed team:
- We clean the base from dirt and dust.
- We mark the level of the upper screed with a laser level.
- We lay the plastic film for waterproofing, always overlapping the canvases, fixing them with tape and removing the edges 200 mm above the level of the screed mark.
- Along the perimeter to the walls we fix the edge (damper) tape.
- We scatter expanded clay on the surface of the base.
- We carry out the leveling of expanded clay from the wall opposite the exit from the room:
- set leveling profiles at a distance slightly shorter than the rule length,
- we set the lower planes of the guides to the calculated level (this moment is especially important in the work),
- leveling rail (rule) we carry out the alignment of expanded clay.
- On a flat surface, we carry out the cutting of GVL sheets, starting from cutting the seam that is extreme to the wall.
- On the surface of the aligned expanded clay, we lay out bridges from scraps of gypsum fiber with a size of at least 50 cm / 50 cm.
- We begin laying GVL from the wall with the doorway, we move from right to left, we fix the joints on adhesive mastic
- Each glued layer is fixed with screws, the step should not be more than 300 mm, the heads of the screws should be recessed to a depth of 1 mm.
- We start each new row by laying the element left over from trimming the previous row, thereby minimizing waste and ensuring the displacement of the end joints of the elements.
- Under linoleum, carpet, PVC laminate, we seal joints and screws with putty.
- Under porcelain stoneware, ceramic and natural stone tiles, we process the surface with a primer for glue.
Reviews
Among the reviews that the dry screed method receives, there are both positive and negative.
Of the pros mention:
- speed and dry work performance,
- the ability to level the floor in any building,
- folding design
- the presence of soundproofing and warming effects.
Discontent causes:
- the high cost of original Knauf materials,
- the fragility of the floors when they are trying to make them from a substitute material (drywall),
- the need to especially dry dry floors in case of flooding.
Good examples and options
Almost any floor covering can be laid on top of a dry floor. Parquet or laminate, carpet or porcelain tile - the choice is left to the owner of the premises and is limited only by his imagination and financial capabilities.
For example, exotic lovers can install Knauf soft and warm cork flooring, designed specifically for use with a dry screed system. Floor cork is characterized by warm and soft tones typical of natural wood, while having high performance.
Fans of vivid effects can pamper themselves by laying vinyl tiles or unusual linoleum on top of dry floors, creating an unusual and memorable design.
In the bedroom or children's room, the dry screed method will allow for quick repairs with laying carpet or evaplast, which will please you with comfort and warmth.
See how to lay a dry screed in the next video.
What is Knauf Tribon?
The universal self-leveling floor KNAUF-Tribon is a material that greatly simplifies the technology of the screed device. It is a dry mixture based on a mixed (complex) binder (gypsum and Portland cement), special modifying additives and quartz sand as a filler
Advantages of Knauf Tribon
- Crack resistant, non-shrink
- It has high compressive strength (more than 20 MPa)
- Has a high setting speed (the ability to walk on the floor after 6 hours)
- Increased solution pot life (up to 60 minutes)
- High mobility (spreadability) of the solution
- Product versatility (screed and leveler at the same time)
- A wide range of layer thickness - from 10 to 60 mm (in some cases and more)
- Contributes to improved indoor climate
- It is applied in the system of heated floors
Areas of use
Indoors with dry and normal humidity conditions on load-bearing substrates for creating self-leveling leveling screeds 10-60 mm thick for subsequent topcoats.
In new construction and repair on concrete and wooden substrates.
To increase the soundproofing properties of the floor and reduce the level of impact noise.
In heated floor systems
Leveling screed from 35 to 60 mm thick on an insulating layer of heat and sound insulating materials
It is used to increase the insulating properties of the floor, as well as to reduce the level of impact noise. In addition, it allows, if necessary, to raise the floor level to the design value. As an insulating layer, it is recommended to use insulating materials based on expanded polystyrene, such as KNAUF Therm® PolPRO and KNAUF Therm® Perimeter. With significant differences in the bearing base and the need for screed installation on laid communications (pipes, cables, etc.), it is recommended to use the KNAUF-Ubo screed as an insulating layer.
Leveling screed with underfloor heating systems
It is used to create a warm floor. The thickness of the screed is calculated from the condition of the minimum screed height above the heating element of at least 35 mm. At the same time, the recommended screed thickness should not exceed 60 mm. This will help to avoid an increase in the energy consumption for heating the screed and reduce heat loss.
1. Assessment of the strength of the bearing base
Base Strength Assessment
You can evaluate the strength of the base using any sharp object (for example, a nail, a self-tapping screw, etc.). It is necessary to draw four parallel lines. Then, at an angle of 45 ° to the first lines, draw parallel lines intersecting them (at least four). The distance between the lines should be from 1 to 1.5 cm.
Solid base - the absence of chips at the points of intersection of lines, a clear pattern of a rhombus, the edges of the lines without obvious notches and destruction.
Weak foundation - the presence of chips at the points of intersection of the lines, a blurred diamond pattern, the edges of the lines have frequent notches and destruction.
In the event that the bearing base is fragile, you should refuse to fill the floor with a contact method in favor of structures on a separation or insulating layer.
2. Priming the surface of the base
Prior to fastening the edge tape, it is necessary to prime the surface of the carrier base. For this, the primer KNAUF-Multigrund or KNAUF-Mittelgrund is used.
Primers must be applied in two stages:
KNAUF-Mittelgrund: dilute the primer with water in a ratio of 1: 2 and apply the first coat to the surface.
KNAUF-Multigrund: apply the first layer without dilution and after drying (at least 6 hours) apply the second layer.
3. Fastening the edge tape
Along the perimeter of the room and around the supporting elements of the building (supports, columns, etc.), it is necessary to install and fix the edge tape. It serves to reduce acoustic noise, provides free deformation of the screed and protects against leakage of the mixture into other rooms through possible gaps in the junction of the wall and floor.
1. On a layer of backing paper
After fastening the edge tape, the apron is unbent and a special KNAUF lining paper is laid. The overlap of adjacent paper sheets should be at least 80 mm. The edges of the paper are not displayed on the wall and are adjacent to the edge tape over the apron.
2. On an insulating layer of heat and sound insulating materials
First, polystyrene plates are laid on the base, after which an edge tape is attached to the upper level of the insulating layer and the apron is unbent. The lining paper is placed on top of the insulating layer and the apron. If the base is uneven and the height difference is more than 10 mm, then prior to laying the insulating material, it is recommended to pre-align with the same KNAUF-Tribon mixture. And only after the leveling screed has dried, an insulating layer and lining paper are laid.
Main advantages
Before you purchase the described system, you must read the reviews about the “Knauf” dry screed, opinions about it will help you make a decision. Thus, among the positive features, consumers highlight the excellent quality and speed of work at home, as well as the savings due to the fact that the building structure can be made more lightweight. Among other things, there can be no restrictions in architectural decisions. The installed system will meet international standards, it is environmentally friendly and creates a favorable microclimate. The design has the ability to breathe, give away or absorb moisture when it is lacking. Inconvenient wet processes do not have to produce. A dry Knauf screed, the pros and cons of which is recommended to consider before visiting the store, can withstand 360 kilograms of weight per square centimeter.
Range
Knauf products include cement and gypsum-cement floors.
Knauf-Ubo cement light screed consists of cement and polystyrene granules. The cost of this product is relatively low.
The Knauf Boden bulk floor is presented in 3 options:
- "Knauf Boden-15" (production of screed from 2 mm to 15 mm),
- "Knauf Boden-25" (production of screed from 10 mm to 25 mm),
- "Knauf Boden-30" (production of screed from 25 to 80 mm).
The type of mixture is selected depending on the thickness of the poured layer. It is based on gypsum, which allows the floor to dry quickly and gives it plasticity. This building material is used for insulation and sound insulation.
Part "Knauf Boden" Extra hard gypsum and quartz sand are included. To prepare the solution, 6.5 liters of water are added per 25 kg of dry matter. The mixture must be gradually poured into water, continuously mixing the solution with a mixer so that there are no dry lumps. Needle roller will help to cope with air bubbles.
It should be used within half an hour.
The finished liquid mixture is applied mechanically or manually. On average, it takes 3 hours to solidify the bulk floor. For the complete hardening of the material, it will take from 2 to 8 days. In each case, this indicator depends on the temperature in the room and the thickness of the poured layer.
Universal self-leveling waterproof floor "Knauf Tribon" It is used to create a particularly strong screed, the thickness of which varies from 1 cm to 6 cm. Any decorative materials can be laid on it without additional surface preparation. In addition to gypsum, Portland cement, quartz sand and special modifying additives are included.
Specifications
The technical characteristics of Knauf dry mixes provide simplicity and speed of installation and excellent performance properties of the coating. They are also distinguished by the following parameters:
- The plasticity of the mortar saves floor installation time.
- The composition of the mixture provides good sound and heat insulation.
- The multi-component composition is easy to prepare for work: you just need to dilute the mixture with water according to the instructions on the package.
Advantages and disadvantages
Product Strengths:
- Self-leveling significantly saves time and effort. The spilled mixture is self-leveling on the basis of the presence of polymer additives.
- The thickness of the layer varies at the request of the owner of the premises. In some cases, a few millimeters is enough, for example, when pouring the finish layer. For other options, you will need a few centimeters, for example, if you decide to use Knauf products also for screed. Layer thickness may depend on the need for additional sound and heat insulation.
- Speed of installation. The solution can be applied within an hour.
- Hardening speed. You can walk on the floor and continue repairs after 6 hours. Basic strength is achieved in two days.
- Paul Knauf does not shrink, does not crack when solidified.
- Durability of plaster bulk floor. This feature is provided by special modifiers.
- The versatility of mixtures. They are suitable for creating heated floors, absolutely any finishing materials (parquet, laminate, tiles, carpets) can be laid on the bulk layer.
- The composition of the mixture includes environmentally friendly components that do not harm human health.
The disadvantages include:
- Fairly high price. For example, the cost of one package of the Knauf Boden mixture is in the range of 450-550 rubles.
- A huge number of fakes due to the high demand for the products of this company. When you purchase such a product, you no longer have to talk about the quality of the bulk floor.
Pouring process
In order that the flooded floor does not exfoliate, it is necessary to use a high-quality primer. If you save on this material, the floor can be completely ruined.
Before pouring, beacons must be installed that control the thickness of the coating. In the corners of the room, at the junction of the floor slabs with the walls, an insulating edge tape must be laid to prevent leakage.
The primed surface should be thoroughly cleaned of dust.
In accordance with the proportions of water and mixture indicated on the package, a solution is kneaded, which is then poured onto the floor, reaching the desired layer thickness. Bulk mixes are plastic, easily spread, resemble a thick jelly in consistency.
If you prepare a self-leveling solution in large portions, you may not have time to fill it. When the assistant prepares the mixture, pouring speed and coating quality increase significantly.
The solution is poured at one point, a little rake is leveled and rolled with a needle roller. Immediately after filling the floor, direct sunlight should not fall on it.
Do not use fans or heaters to speed up solidification.
Negative points
Do not use this floor system in the garage, since heavily moving machinery will break and shift sheets. In addition, you should be prepared for a sufficiently low moisture resistance. If moisture gets in, the surface will need to be opened for long-term drying or complete replacement. Therefore, such structures are not recommended for use on basement floors, in unheated rooms, basements and during the installation of warm water floors.
Considering the subtleties and nuances of the “Knauf” dry screed, you will realize that you will not have to use wet processes during installation. However, this does not exclude some inconvenience, which is the high spread of dust when backfilling expanded clay. That is why craftsmen must work with respirators and goggles. When comparing the cost with other methods of laying floors, it can be noted that Knauf systems are much more expensive.
Negative reviews
Consumers sometimes refuse the “Knauf” dry screed for the reason that it requires the use of additional materials, which is accompanied by costs. This is due to the fear of moisture, while leaks have simply disastrous consequences. A vapor barrier layer will need to be laid on the floors, which will protect the backfill located on it from moisture that occurs when the floor is in contact. Moisture vapors can penetrate from lower rooms or concrete, as well as through walls. To ensure vapor and moisture protection, it is recommended to use a polyethylene film, the thickness of which can vary from 200 to 250 microns. This is true for reinforced concrete floors. If we are talking about wood, it is best to use bituminized paper or glassine. Do not give up on modern vapor barrier.
Dry screed “Knauf”, negative reviews about which also exist, according to users, requires the presence of a fairly impressive thickness of the backfill. This affects the reduction in ceiling height. The layer thickness can vary from 30 to 50 millimeters, however, the final layer will depend on the size of the bumps. That is why it is advisable to level the floor surface before carrying out the work. Engineering communications, as well as other equipment will affect the thickness of the backfill. Consumers argue that a dry screed system can become a place of fungus or mold formation under inappropriate conditions. At the same time, repeated repairs cannot be avoided, which will be accompanied by costs. This indicates significant application limitations. Buyers argue that during the operation of such a floor, it is necessary to constantly monitor the microclimate, and the room should not have sudden changes in temperature and humidity.
Preparatory work
Initially, a rough foundation will need to be prepared. Under the elements of dry backfill, plumbing communications can be laid, however, only before using expanded clay. Before installing the floor, it is necessary to prepare a concrete surface, while all the gaps and cracks between the plates are sealed with cement mortar of grade M 500. After that, the entire area is cleaned of debris and foreign objects. If there are slight irregularities of up to 5 millimeters on the base, then such floors can be leveled using corrugated cardboard. Then how to deal with local irregularities up to 20 millimeters is recommended with the help of repair mixtures. Well proven, for example, Vetonit 4000. If there are more impressive potholes, then it is recommended to fill them with small-fraction expanded clay.With it, the slope of the base is leveled, if any.
If it is necessary to warm the floors before laying a dry screed, it is necessary to first level out with putty, which can be replaced with a sand-cement mixture. Polystyrene plates for thermal insulation are laid on such a surface. After preparing the base, a waterproofing layer is laid, since expanded clay does not tolerate contact with moisture. Dry screed “Knauf”, the reviews, the pros and cons of which are discussed in detail in the article, should be laid on a plastic film, covered with an overlap of 20 centimeters. At the walls, the edges of the waterproofing should be 2 cm above the precast floor. This is necessary to ensure vapor barrier. Instead of a film, you can use waxed or corrugated paper, modern vapor barrier "Svetofol" or glassine.
Filling and leveling the dry screed
Expanded clay used in the arrangement of prefabricated screed is an excellent heat insulating material. It should have a small fraction from 2 to 4 millimeters, but the lining of large elements can not be taken, since the floors will sag. Before laying expanded clay sand, beacons must be installed using the laser level, and then it is recommended to apply the trapezoidal rule.
Which sheets are best used as the outer layer?
Dry screed “Knauf”, negative reviews about which often enough force users to opt for other materials, may include GVL or GKL sheets. These two materials are successfully used today in the arrangement of dry screeds. GKL, for example, is a plasterboard sheet, the edges of which are lined with cardboard, with the exception of the end part. In order for the material to be durable, binders are added to the gypsum. Cardboard adheres to gypsum with special adhesive additives. Sheets are well bent and cut, and in prefabricated floors they are used somewhat less often in comparison with other types.
GVL is a gypsum fiber sheet that is completely uniform in composition. It is stronger than drywall and is more suitable for prefabricated floors. Its manufacture is carried out not by pressing, but through cellulose reinforcement. This material is also characterized by higher fire resistance. In addition, GVL will cost less.
Sheet stacking
Dry screed “Knauf”, the process of use, the study of reviews of which will eliminate errors, is stacked from the door, while the gap in the joints should be one millimeter. The first layer is covered with adhesive, and then the second is laid. The sheets are arranged across with the same gap. Cloths in the second layer are fixed with screws for GVL.
