Is it possible to finish screeding the floors in one day and begin laying the finishing coating the next day? Not so long ago, this seemed unrealistic, because a “wet” cement screed requires at least 28 days for final drying. But about 15 years ago, the revolutionary technology of Knauf loose floors appeared, which changed the understanding of this process. One of the names assigned to it for this reason is “superfloor Knauf”.
Today, there is probably no person, one way or another connected with the construction industry, who has not heard about this company, which produces a variety of finishing and building materials, as well as paint and varnish products, system components suspended ceilings, hydro, heat and sound insulating materials, fasteners, various tools.
But most of all, this company is known for its plasterboard technology, perfected to the smallest detail. facing materials, being its ancestor. Founded by the two Knauf brothers in 1932 as a manufacturer of gypsum building mixtures, already in the 50s the company began producing the first plasterboard materials, soon becoming the undisputed leader in this technology. And today we can confidently say that “Knauf” and drywall are two inextricably linked concepts.
The Knauf screed method is essentially a long-known technology of semi-dry or dry prefabricated screed, when sheet panels of the rough coating are installed on a substrate made of a thin layer of finely dispersed material. The soft and seemingly loose backfill pressed by them becomes strong and hard, capable of withstanding quite large loads.
In the Knauf company method, expanded clay sand of a very fine fraction with a granule size not exceeding the standard 4 mm is used for this. After leveling the backfill using the “beacon” rule, it is covered with sheets of gypsum fiber material. The backfill thickness should be in the range from 30 to 100 mm.
Gypsum fiber sheets (GVL) differ from plasterboard in the absence of a top paper coating and are a uniform mixture of gypsum and cellulose fibers reinforcing it. Possessing high strength and fire resistance, they are also quite environmentally friendly and chemically safe.
Issued structural elements Knauf superfloor in the form of panels glued together from two GVL sheets with dimensions of 1200 × 600 × 10 mm offset relative to each other to form folds along the perimeter 50 mm wide, along which they are fastened when laid together using adhesive mastic and self-tapping screws. The total thickness of the resulting superfloor coating is 20 mm.
Advantages
- The main advantage of this technology is the absence of “wet” materials and operations. This is especially valuable not so much during the construction of new buildings, but when performing repair work in existing ones, as it eliminates possible leaks and the penetration of moisture and dampness into adjacent rooms.
- High execution speed installation work. There is no need to use special mechanisms. Laying a Knauf superfloor in a 20 m² room by a team of two people during the working day, along with delivery and unloading work, is quite a common thing.
- Immediately after GVL installation panels, the floors are ready for laying the finishing coating and receiving work loads.
- In addition to the speed of installation, Knauf floors are distinguished by high speed and ease of dismantling work in case of disassembly. GVL sheets are removed using a regular jigsaw, then the backfill is collected with a shovel or scoop.
- The small total thickness of the entire “pie” of dry screed - from 50 mm with a backfill layer thickness of 30 mm - causes a very low loss of height and volume of the room.
- The total total weight of the floor structure is significantly less than with traditional ways screeds. This significantly reduces the load on load-bearing elements floors and the structure of the entire building.
- Low thermal conductivity makes it possible to avoid additional layers of thermal insulators for thin finishing coatings such as laminate, linoleum, cork, etc.
- The high sound insulation properties of Knauf floors are significantly superior to wooden and parquet flooring in this parameter.
- Excellent fire safety.
- Possibility of installation at any time of the year.
- Knauf floors are also highly environmentally friendly and chemically inert.
Main technical characteristics:
- dimensions of the panels together with folds 50 mm wide - 1250×650×20 mm;
- area covered by one element - 0.75 m²;
- weight of one panel - no more than 18 kg;
- Brinell hardness - 22 MPa (220 kgf/cm²);
- the compressive strength of expanded clay backfill is at least 10 MPa;
- thermal conductivity - 0.25~0.35 W/(m²×°K);
- sound insulation: 58 dB - from airborne noise and 55 dB - from impact noise;
- fire safety in terms of flammability, flammability, smoke generation and gas toxicity classes - G1, B1, D1, T1;
Flaws
Speaking of disadvantages Knauf technologies, then there are practically none, although many here call this material “hydrophobia”, but leaks and flooding can thoroughly ruin any type of flooring. Even if the consequences of such accidents do not appear immediately, after some time they will certainly make themselves felt in the form of fungus, mold and rot. But the ease of dismantling Knauf floors allows you to replace them with the least labor costs compared to other types of coatings.
Many homeowners and master installers, for reasons of economy, believe that on the upper floors of buildings and structures, laying a moisture-proof film under the base of a dry screed can be neglected. This is a serious mistake, since moisture can enter through the floor slabs from neighboring premises. In addition, such a film also serves as a vapor barrier, protecting materials from condensation.
Laying method
In the simplest method of constructive technology of dry screed discussed here, which has the designation “Alpha” in Knauf company terminology, a single-layer installation of gypsum fiber board is used, but there are other options that involve a more complex “pie” using additional layers of polystyrene foam or porous fiber acoustic and thermal insulation materials from this company.
Required materials:
Required tools:
- drill, screwdriver;
- jigsaw;
- drywall knife;
- measuring instruments: tape measure, meter, square, level;
- metal profile for installing “beacons”;
- Rule for leveling the backfill layer along the beacons.
Step by step guide
- The surface of the floor slabs under the floor base must be well cleared of debris. Protruding ends of reinforcement, wires, nails, and screws must be carefully cut off and removed. Large irregularities and pieces of crushed stone protruding from the concrete should be carefully knocked off with a chisel.
- On a prepared base vapor barrier film is spread with adjacent sheets overlapping each other by at least 200 mm. Its edges along the perimeter of the room should extend onto the walls above the level of the future floor.
- Then a vertical edge strip is installed along all walls, designed to compensate for thermal deformations of the Knauf superfloor panels. The compensation gap at the edges is a very important condition for this technology. It allows you to avoid swelling of the floor when the temperature in the room changes.
- Along the line of the proposed installation metal profiles The lighthouses are covered with a small mound of expanded clay along the length. Beacons are pressed into it from above, adjusted to the level, based on the total backfill thickness of no more than 10 cm. If flooring is replaced in only one room of the house, the level of the future flooring should “come” to the corresponding level in the remaining rooms.
- In the space between the beacons, an expanded clay layer is filled, which is then leveled with a rule. One of the advantages of Knauf flooring is the ability to backfill and lay the covering not completely in the entire room, but in parts.
- Then the beacons are removed, and the traces from them are sprinkled with a small amount of expanded clay. To the corner from which the installation of gypsum board sheets will begin, a “path” of several free panels is laid, along which you can move without spoiling the rest of the backfill.
- The folds of the gypsum fiber board panels adjacent to the walls and partitions must be cut so that their thickness in these places is double. The first row of panels is laid out along one of the walls. Work should begin from the wall of the room opposite the entrance, gradually moving towards front door. Before laying the next row, the folds of the previous one are lubricated with glue or mastic.
- The sheets of each next row are laid with an offset of at least 250 mm relative to the previous one. The formation of cross-shaped joints is not allowed. Then the glued joints are fastened with screws in increments not exceeding 300 mm.
- After the floor has been laid in the entire room, everything The joints between the sheets should be filled with gypsum putty. Knauf.
- Before applying the finishing coat, Knauf superfloor must be coated with a deep penetration primer.
To significantly increase the strength of the coating, you can lay a second layer of gypsum fiber board panels by changing the laying direction perpendicular to the sheets of the first layer.
Conclusions
Knauf superfloor technology is perfectly suited for underfloor heating systems that are so popular today. And the high thermal insulation properties of bulk floors significantly reduce the heat loss of the room through its base, which significantly increases the energy efficiency of any heating systems. We can confidently say that the cost of installing Knauf loose floors with good overall thermal insulation of the house will pay off within 2-3 years due to savings on heating.
Preface. Many people want to install a Knauf superfloor with their own hands in a room or on a balcony. Floors using this technology are lightweight, unlike concrete floors; in addition, they are warm and reliable. When installing a superfloor, less dirt is generated than when self-leveling floors. We will analyze the construction of Knauf floor elements on our own and show video instructions for installing dry floors at the end of the material from professionals.
4. Laying floor elements
The main rule when installing floor elements is not to move the sheet along the backfill. You just need to place the sheet on top of the expanded clay backfill and secure it. Although this is not so easy to do, since one sheet weighs about 17 kg. Doing the work together will make it much easier to lay the subfloor. On all sheets running along the walls, the fold is removed.
5. Fastening sheets with screws and glue
The sheets are laid on the floor with the seam offset, similar to brickwork or facade insulation with foam plastic. The floor element consists of two gypsum fiber sheets glued together, so there remains a field for attaching the sheet with self-tapping screws. Each sheet of Knauf flooring is secured around the entire perimeter with wood screws every 10-15 cm. For greater strength, the manufacturer recommends gluing the seams with PVA.
Features of Knauf superfloor technology
Dry screed Knauf superfloor is faster than concrete screed. This is a prefabricated system that significantly reduces the labor intensity of leveling and insulating the floor. Knauf floors significantly reduce the load on the floors, as they distribute the weight; in addition, the expanded clay layer significantly increases the thermal insulation of the premises. Typically, floor elements are laid on top of expanded clay filling with a fine fraction of up to 5 mm.
Laying floor elements is quite simple, but requires some skill. This technology has many subtleties; following the manufacturer’s instructions will give excellent results. To install a superfloor yourself, watch a video lesson from professional builders and study the process in detail. You should not rush into this matter in order to end up with perfectly smooth and warm floors in your house.
Traditionally, plank flooring or sand-cement screed serves as a subfloor. The appearance of Knauf floors was a real technological breakthrough. Since the advent of this flooring technology, no manufacturer in this construction sector has been able to create anything more economical.
Construction materials produced by Knauf have widest distribution on the territory of our country. They are distinguished by impeccable quality, in an assortment Knauf products There are several dozen varieties of dry mixes, primers, sheet materials(tongue-and-groove, plasterboard, gypsum-fiber sheets).
Loose floors produced by this company are environmentally friendly, fire-resistant safe material with excellent thermal and sound insulation properties. They are used as in capital construction, and during repair work. Floors from Knauf have the following positive qualities:
- fire resistance. GVL slabs are not subject to combustion;
- environmental friendliness;
- simple installation with minimal time costs;
- compliance with the highest construction standards;
- creating an optimal microclimate;
- Knauf floors can be used immediately after installation;
- you can use any material for the final coating: laminate, carpet, parquet, porcelain stoneware, or linoleum;
- for laying such a floor, no careful preparation of the surface is required; technological process installation there are no operations requiring the preparation of any solutions;
- During operation, the coating does not deform, does not creak, and there are no cracks or breaks on it. Total weight floors are small and do not create a significant load on the floors and load-bearing structures;
- Floor installation can be done in winter in an unheated building, the main thing is that there is no high humidity in it.
And another important advantage is that it is the most cost-effective floor covering.
| KNAUF-superfloor Floor element (EP). Characteristic | Description |
|---|---|
| Manufacturing method | KNAUF-superpol. A factory-ready product made from gypsum fiber moisture-resistant KNAUF supersheets (GVLV) for creating a “dry” screed - a prefabricated floor base. Floor elements are made by gluing two moisture-resistant gypsum fiber sheets(GVLV according to GOST R 51829-2001) with dimensions of 1200x600x20 mm with mutual displacement in two perpendicular directions and the formation of folds 50 mm wide along the perimeter of the products. The total thickness of the EP is 20 mm. |
| Scope of application | It is used for constructing a prefabricated floor base in buildings for various purposes. |
| Characteristics | Dimensions, mm: 1200x600x20. Element mass, kg: about 18. Rebate width, mm – bottom layer – top layer: 50. Useful area of the element, m2: 0.75. Thermal conductivity coefficient, W/m C: from 0.22 to 0.36. Heat absorption coefficient, W/m C: no more than 6.2. Hardness of the front surface, MPa: not less than 20. Surface water absorption, kg/m2: no more than 1.0. Vapor permeability coefficient, Mg/m h Pa: 0.12. Specific effective activity of natural radionuclides, Bq/kg: no more than 370. Packaging: Bag, 70 elements (50.4 m2). With shrink film. |
| Firefighter technical specifications | KNAUF-superfloor (floor element) is assigned to the class fire danger KM 1, which is confirmed by a certificate of compliance with the requirements Federal Law RF No. 123-FZ " Technical regulations on fire safety requirements." Flammability group according to GOST 30244-94: G1. Toxicity group according to GOST 12.1.044-89: T1. Flame propagation group according to GOST R 51032-97: RG 1. |
| Recommendations | Before use, floor elements must undergo acclimatization (adaptation) in the room. In the installation area, floor elements must be stored horizontally (flat) on a flat surface. The design of the prefabricated floor base (screed) should not have slopes. In cases of installation of a prefabricated floor base (screed) in wet areas(bathrooms) lay KNAUF-Flachendicht waterproofing tape at the joints of the floor and walls, and cover the floor surface with KNAUF-Flachendicht waterproofing. If the floor covering is a thin elastic material, it is recommended to cover the base of the floor with a layer of self-leveling putty KNAUF-Boden 15 (Nivelirspachtel 415) with a thickness of at least 2 mm. |
What's included
Knauf floors are made by gluing two moisture-resistant gypsum fiber sheets (gypsum fiber). The thickness of the resulting sheet is 2 cm, linear dimensions– 1200x600 mm, folds measuring 5 cm are arranged around the perimeter.
Also integral part Knauf flooring is fine-grained expanded clay, the quantity depends on the thickness of the layer that is required at a given construction site. If the layer exceeds 6 cm, laying a second layer of gypsum fiber boards is required. The kit usually includes plastic film and screws. After correct installation Knauf floors create a flat, durable surface that can withstand significant loads - up to 500 kg per sq. m.
Tools and material required for installation
- Construction vacuum cleaner.
- Paint brush.
- Construction gypsum.
- Level (regular building or water level).
- Deep penetration soil.
- Pencil or marker.
- Hacksaw for metal.
- Self-tapping screws the right size(from 2 cm).
- Metal guides (rack profile, 60 mm wide or metal beacons).
- Waterproofing.
- The rule is metal.
- Glue (PVA or liquid nails).
- Screwdriver.
- Spatula.
Preparing the base
In the case when the floor is laid during renovation work, it is necessary to completely dismantle the old covering down to the concrete (or wooden) base. For the installation of Knauf floors, the base may not be completely flat, but it must be taken into account that the backfill layer should not be more than 10-12 cm.
It is very important in the process of preparing for installation to thoroughly clean the entire area from dirt and construction debris and seal large potholes/cracks with concrete or gypsum mixture. It is advisable to vacuum the surface by a professional construction vacuum cleaner and treat with deep penetration primer. After the soil has dried, you can begin installing insulation.
Hydro- and vapor barrier device
This is an important technological stage and must be approached responsibly - a high-quality insulating layer will help you get rid of floor problems for many years. If moisture penetrates, then individual sections of the floor may sag and the slabs may swell, leading to deformation of the flooring. First of all, it is necessary to check the horizontalness of the surface using a level and make marks on the walls along the entire perimeter of the room that determine the level of backfill. For waterproofing, you can use rolled self-adhesive waterproofing materials, PVC film(thickness of at least 200 microns) or vapor barrier. The waterproofing film is laid with an overlap of about 20 cm, the joints are fixed with tape.
The waterproofing film is laid with an overlap
Waterproofing on walls should be installed up to the marks that limit the backfill layer.
For wooden floors, glassine can be used as insulation to protect against moisture. Paper impregnated with bitumen is also suitable.
After installing the waterproofing, you should proceed to creating sound insulation. A 10-centimeter layer of insulation (edge tape) is laid along the walls, which will prevent the floor from deforming and create sound insulation. Regular foam tape can also serve as an insulator. They can be self-adhesive or regular (attached with construction tape or a stapler). A good option There will also be the use of a special damper tape.
Bulk materials base
The base for GVL slabs can be made not only from expanded clay and silica sand, but also from other types of sand. You can also use screenings or slag (small fraction). These materials are characterized by flowability, almost no precipitation, and have high porosity. They have a low hygroscopicity rate, so they are optimally suited for Knauf flooring.
The volume required for backfilling depends on the size of the room and the size of the layer, which, in turn, is determined by the presence of communications and the existing slope of the surface. Before you start backfilling, you need to install beacons - guides, with the help of which the dry screed will be leveled. The two extreme profiles (or beacons) are placed at opposite walls strictly horizontally. They must be placed parallel to each other, the distance from the wall is about 15 cm.
You can put it under beacons wooden blocks or small pieces ceramic tiles, but it is better to make support poles from plaster. Then the cord is stretched and intermediate profiles are installed, parallel to the others, at a distance of 1.5 meters from each other. After installing the beacons, expanded clay is poured in and carefully leveled using a metal rule.
Leveling the backfill using a special rule
After leveling, the beacons must be removed very carefully (after arranging temporary sites made of thick plywood measuring approximately 60 by 60 cm for movement on them) and adding expanded clay, carefully level it with a metal spatula without disturbing the surface level. On large areas, installation should be carried out in stages: having completely covered a certain area of the floor, you should begin further leveling.
On an absolutely flat surface with no deviations from the horizontal, expanded clay backfill is not needed. Instead, you can tightly lay sheets of polystyrene foam (extruded), making precise cutting. Install Knauf floors on polystyrene foam, following conventional technology.
Having compacted the expanded clay, you can begin installing gypsum fiber board sheets. Prefabricated floor elements from the Knauf company are easy to install, you just need to take your time and carefully follow all installation technology. It is better to start laying sheets from the door; on the first sheets, you should remove the folds on one side (from the walls) so that they lie flat and do not sink into the expanded clay. The installation scheme is “bricked”, with the joints offset by half of the next sheet. The first sheets must be carefully leveled; the level of the assembled floor will depend on how level they lie. The folds are glued together and scrolled with self-tapping screws every 10-15 cm.
Fastening sheets with self-tapping screws
You can cut GVL sheets with a hacksaw or a regular hacksaw with a fine tooth. It is necessary to ensure that expanded clay or other bulk material does not get into the joints. Knauf floors can be assembled throughout the entire apartment at once, while maintaining one level. Installation should be done with a partner; in one working day you can lay the floor on an area of more than 100 square meters. m.
Knauf floors have stood the test of time, the manufacturer guarantees truly high quality, but superfloors also have their drawbacks:
- You almost always have to cut off the fold of the sheets adjacent to the wall. This ultimately leads to a slight subsidence of the floor during operation;
- By removing the beacons and adding a small amount of expanded clay, it is quite difficult to maintain a completely flat surface, which is necessary for installation. But beacons left under the floor can also lead to deformation of the coating.
Knauf floors are susceptible to moisture and require careful waterproofing.
During the installation process, you need to ensure that the bulk material is completely dry, otherwise the floor may “lead.” Knauf floors are not recommended for installation in basements and ground floors. When laying such a floor in bathrooms and kitchens, it is necessary to carry out high-quality waterproofing and install a finishing coating that does not allow moisture to pass through. Such a floor should not be installed in rooms with heavy loads - in office and municipal buildings, in production workshops. Floors Knauf – great option for an apartment or private house with good ventilation system. If the installation was carried out efficiently, this floor will serve you for a very long time.
An example of laying tiles on a KNAUF floor
Video - DIY Knauf floors
In most cases, the floor structure is a screed. The most common and popular is the “wet method” based on cement-sand mortar. But dry (prefabricated) technology, although used much less frequently, is a much more economically attractive method. Bulk flooring can be used both for construction and renovation work in residential and non-residential premises. The leading position in the dry screed floor market is rightfully occupied by German company Knauf.
Characteristics of Knauf loose floor
The Knauf company is widely known in construction market and has maintained the high quality of its materials for many years. She produces plasterboard sheets, tongue-and-groove slabs, hypo-fiber sheets and a variety of liquid construction mixtures, including primers, putties, adhesives, etc. But their hallmark in our country is Knauf loose floors, which will be discussed in this article.
Knauf superlist
This is an environmentally friendly material high quality. Excellent for premises that have increased fire safety requirements. It has good sound and heat insulating properties. It is used as a compensating layer if the thickness of the backfill does not exceed 15 cm. Sheet dimensions are 250x120x1 cm and 250x120x1.25 cm.
Peculiarities:
- high fire resistance;
- high laying speed;
- there is no need for “wet” stages of work;
- creates a good indoor microclimate;
- meets high international standards.
Moisture-resistant Knauf supersheet
Retains all the advantages of conventional Knauf sheets, but at the same time is highly moisture resistant. Sheet dimensions are 250x120x1 cm and 250x120x1.25 cm.
Floor elements Knauf-superfloor
They are produced at the factory from moisture-resistant gypsum fiber Knauf supersheets. When making them, two sheets with dimensions of 150x50x1 cm are glued together, resulting in a total thickness of 2 cm. There are folds 5 cm wide along their entire perimeter.
The Knauf bulk floor consists of a layer of PVC film, expanded clay for leveling and the floor elements themselves. The main advantages are short terms execution of work, absence of “dirty” work, creation of a perfectly level floor base and convenient location of all communications. This floor is suitable for laying not only on a flat surface, but also on uneven surfaces with cracks, depressions or bumps.
Advantages:
- an absolutely flat and durable floor base is created, capable of withstanding a load of 500 kg/m2;
- hypoallergenic material;
- throughout the entire operational life, no cracks appear and there are no squeaks;
- after installation, the floor is immediately ready for use;
- any plasterboard partitions can be installed on the Knauf loose floor;
- excellent sound insulation (especially important for residents of multi-storey buildings), which cannot be said about cement screed or self-leveling floors;
- there is no risk of flooding the neighbors below, because no water is used during operation;
- Knauf flooring is much warmer than concrete screed;
- All work is completed quickly and without loss of quality. To make a floor in a room of 18 meters, if all the materials and tools are available, professionals will need no more than 3 hours. And this is especially important for those who are making repairs in the apartment in which they live;
- You can fill the floor in rooms one at a time without losing the level.
Any floor covering can be installed on the resulting flat surface of the bulk floor: parquet, laminate, tiles or porcelain stoneware.
The only thing that is prohibited is the installation of warm water floors; they are replaced with electric ones warm floors. Thanks to the layer of expanded clay backfill, the floor has excellent thermal insulation.
- If repairs or reconstruction of the floor are carried out in old buildings or in houses with wooden floors. Because it can significantly reduce the load on the supporting structures of the house.
- In cases where the subfloor needs to be prepared as quickly as possible.
- In the cold season, when it is not possible to make a cement-sand screed.
- If necessary, install electric heated floors in wooden interfloor ceilings.
Do-it-yourself Knauf bulk floor
There is nothing difficult about making it yourself. The main thing is to purchase materials, prepare tools and follow step-by-step instructions.
Preparation of the base surface
If produced renovation work, then first the old floor covering is removed. IN perfect alignment surface is not necessary, but all construction waste, including from cracks.
Installation of a vapor and moisture insulation layer
This is an important stage of work on which the life of the floor depends. The fact is that moisture is destructive for loose floors; under its influence, the slabs swell and the surface covering deteriorates. A layer of PVC or vapor barrier film placed under the backfill will protect it from moisture, which will inevitably form on the interfloor floor.
Using a level (preferably a laser or water level), markings of the top level of backfill are applied to the walls.
Its height depends on the unevenness of the floor base, and varies from two to six centimeters. Another 2 cm of thickness of the prefabricated base will be added to the resulting height - this is exactly how much the floor level will eventually rise. Then the film is laid on the floor with an overlap of at least 20-25 cm and taped with construction tape. It must extend onto the walls up to the previously set marks and be secured with tape. Modern vapor barrier materials can be used as a film; 200 micron thick polyethylene film is also suitable for concrete floors, and bituminized paper or glassine is suitable for wooden floors.
Advice: before laying the moisture-resistant film, you should seal all holes and cracks in the surface of the base using quickly hardening alabaster. If there are wires, they are placed in the corrugation in advance and pressed to the floor. It is necessary to take into account that the minimum layer of expanded clay over a corrugated pipe is 2 cm.
Sound insulation installation
This stage allows you to completely eliminate sound bridges and protect the floor from deformation due to thermal expansion. To do this, a gap of 10 cm is left along the perimeter of the entire room along the walls, into which the heat-insulating material is placed.
You can limit yourself to foam rubber edge tape, which has a thickness of 1 cm and a width of 10 cm. They are available for sale in self-adhesive and simple ones, which are attached to regular tape.
Expanded clay backfill
Bulk material, which is expanded clay, is necessary to create a flat surface, as well as for heat and sound insulation. Expanded clay is poured onto the film and leveled according to the marked markings using the rule. Silica or quartz sand, expanded perlite sand, fine-grained slag or screenings from expanded clay production can be used as backfill material. All these materials have low hygroscopicity, practically do not settle, have high porosity and good flowability.
The thickness of the backfill layer directly depends on the degree of unevenness of the floor slab and on the need for installation in it engineering communications.
On average, a layer thickness of 3-5 cm is sufficient, but if it exceeds 6 cm, then the screed will need to be reinforced with an additional layer of slabs.
How to properly fill dry screed
- The first profile is installed near the wall, and all subsequent ones are installed at a distance of 1.5 m from each other (rule length). They should be located parallel to each other;
- then the height of the profile points is determined and the thread is pulled. To change the height of the profiles, remnants of slabs or planks are placed under them;
- After completing all work, you should check the guide profile again with a level. To avoid its deflection, the supports under it are located at least every 70 cm;
- Expanded clay is poured along the prepared guides and leveled with a rule or a wide spatula. These works are carried out in a respirator due to the large volume of dust;
- when the layer is leveled, the profile is taken out along with the supports, and the resulting holes are filled with expanded clay and leveled. After which everything is compacted;
- If in the future you will have to lay the prefabricated floor from the door opposite the entrance, then you should take care of the “islands”. They are made from squares of chipboard, gypsum fiber board or plywood and laid on a layer of expanded clay;
If the base surface is perfectly flat, there is no need for dry backfill; it is replaced with sheets of extruded polystyrene foam. Also thermal insulation materials(EPS, mineral wool, glass wool, etc.) is also used together with dry backfill when it is necessary to enhance the thermal insulation of the floor. The insulation boards must fit tightly to each other, excluding even small gaps. An edge strip is placed along the walls.
Laying gypsum fiber sheets
Laying sheets on a dry screed begins from the door so that there is no need to walk on it during work. For dry screeds, chipboard sheets, moisture-resistant plywood, OSB, moisture resistant drywall or asbestos sheets. But the most durable and long-lasting material is the Knauf prefabricated floor elements. It can be simply gypsum fiber sheets glued in two layers or with an additional polystyrene foam layer.
The assembly of the first row is very important, as it is decisive for the further progress of work.
It's better to do this work together. Since the weight of one sheet is 17 kg, it is very difficult to hold it with outstretched arms. The folds on the first sheets are immediately cut off; this is done so that the sheet lies flat on the surface and does not go deep when stepped on into the expanded clay backfill.
The sheets are stacked according to the principle brickwork, that is, with offset joints.
Thanks to this arrangement, a place is created for securing adjacent sheets. The screws should be screwed through the folds along the perimeter of each sheet at a distance of 15 cm from each other. For additional strength, all seams are glued with PVA glue.
Knauf loose floor video
Knauf loose floor technology. How to avoid installation mistakes
Despite the fact that Knauf superfloor is a high-quality technology for installing loose floors that has been proven over the years, it also has disadvantages.
The first drawback concerns not so much the technology as the lack of professional tools for its installation in Russia. Official representatives provide training videos of all stages of work, but there is simply no equipment for the work in their catalogs.
The fold at the sheets closest to the wall is permanently cut off, which is the worst mistake that will certainly lead to sagging of the floor in this place.
Beacons left in the backfill lead to deformation of the prefabricated flooring. Expanded clay will still shrink over time, and the beacons will remain in place, which will cause problems in the future.
Particular attention must be paid to the moisture content of expanded clay. If it is not sufficiently dried, deformation of the floor cannot be avoided.
At correct installation Knauf loose floor has only positive reviews. It is durable, strong and safe for human health. Excellent for use in residential premises and in places with high traffic.
Price for Knauf loose floors
The formation of the cost of a Knauf loose floor depends on several components. With a floor thickness of 5-8 cm including installation work, a square meter of floor will cost 1300-1500 rubles.
To hide utility lines, a total floor thickness of 7-8 cm will be required. The price will be about 1500 rubles, of which materials - 900-1000 rubles, and everything else for the work. Doing all the work yourself is much cheaper, but without sufficient experience it will take much longer. So, for professionals, it will take only 1-2 days to install a floor on 50 square meters, and if you do it yourself, it will take at least twice as long.
Approximate prices for materials for Knauf screed flooring:
- moisture-resistant sheets - 320r/m2;
- expanded clay - 1500r/m3;
- moisture-resistant film - 20 rubles/linear meter;
- edge tape - 180r/skein;
- self-tapping screws - from 200r/pack.
It's no secret that the floor base must meet all modern building regulations: strength, reliability, no differences in height. Factors such as installation speed, time before laying the finishing coating, and how soon it will be possible to walk on the new floor are also important.
Advantages and benefits of KNAUF-superfloor
No wet processes
Does not require drying. Laying of finishing coatings - 2U hours after installation of the system.
Easy to assemble
Quick and high-quality installation with your own hands.
Light weight
Does not overload load-bearing structures.
Soundproofing
It will protect against noise and save your neighbors’ nerves.
Thermal insulation
Warm material that allows you to feel the beauty of comfort.
Strength and durability Reliability, proven over more than 10 years of operation in various premises.
Environmental friendliness
Meets the highest requirements of eco-standards.
KNAUF superfloor design
To the question, is it possible to combine all this in one design, without using a great variety various materials, the KNAUF company answers yes. This is possible if you use lightweight floor structures consisting of KNAUF-superfloor floor elements (EP) and KNAUF dry backfill.
What makes KNAUF-superfloor unique?
The KNAUF-superfloor structure is a prefabricated system consisting of gypsum fiber sheets (floor elements) and KNAUF dry expanded clay backfill.
It is used on both wood and concrete foundations, allows you to level out large differences in height - up to 10 centimeters.
The lower part of the system is a special dry backfill made of fine expanded clay, which is laid on a vapor barrier film. Floor elements are laid on top, which have production dimensions of 1,200-600 * 20 mm.
In 8 hours, 1 person can install up to 30 square meters floor - perfectly flat, ready for any finishing coating, be it laminate, tile, parquet board, carpet or linoleum.
There are no wet processes in this technology, so no time is wasted waiting for the surface to dry.
Among the advantages of the KNAUF-superfloor system is also the low weight of the structure, which allows it to be used when renovating dilapidated premises.
KNAUF superfloor - do-it-yourself installation and installation
1. Using a laser level or other means, determine the level of the base and lay plastic film on it.
2. Install a special edge strip along the perimeter of the enclosing structures adjacent to the prefabricated floor base.
3. Level the dry backfill using a set of slats or other devices.
4. Before laying the sheets adjacent to the wall, use a special knife, hacksaw or jigsaw to remove the fold.
5. Evenly distribute special dry KNAUF backfill over the surface at the rate of 10 liters per m2 with a layer thickness of 1 cm.
6. Start laying floor elements from the wall with doorway from right to left. The cut side of the element should face the wall, and the protruding ridge should face to the side.
7. Apply one or two strips of adhesive mastic to the ridge of the laid floor element. Place the next element and secure it with special screws for GVLV.
8. The screed is ready! If necessary, seal joints and screw fastening points with putty.