Dry screed “Knauf”, negative reviews of which are interspersed with positive, is a system stacked according to technology that eliminates wet processes. If you still cannot decide which technique to equip the floor with, then you can compare the screed described with that made of concrete. In the latter case, the operation of the room will be possible only after 28 days, but if we are talking about a dry type screed, then you can move on such a surface in two days.
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 often 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 soundproofing floors.
If the deadlines are limited, it is best to use a “Knauf” dry 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. Exposure to aggressive substances is not allowed, and mechanical stresses should be characterized by low 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, which 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 along the leveling layer of the backfill.
For reference
Super floor “Knauf” (dry screed) should be used in rooms where the temperature does not fall below +10 degrees. Whereas humidity can vary from 60 to 70%.
Main advantages
Before you will be able to 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 distinguish excellent quality and speed of work at home, as well as 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. The 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.
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 understand that during installation you will not have to use wet processes. However, this does not exclude some inconvenience, which is a 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 it comes in contact with the floor. 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 plastic film whose thickness can vary from 200 to 250 microns. This is true for reinforced concrete floors. If it comes to 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 there should not be sudden changes in temperature and humidity in the room.
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 minor 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 the dry screed, it is first necessary to level the 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.
Features of laying the Knauf system
The “Knauf” dry screed, for and against which there were an approximately equal number of users, as described in detail above, should not come in contact with the walls, since an insulating contour tape 10 centimeters wide is laid around the perimeter. Its thickness should be 10 millimeters. As the material, you can use polymer wool. With the help of an edge tape, it will be possible to compensate for the deformed expansion. The filling insulation will need to be poured onto the floor and leveled using a rail. You should start from the wall, which is located opposite the entrance. Material ramming is done manually.
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, stacks from the doors, 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. The canvases in the second layer are fixed with screws for GVL.