Any modern floor covering requires pre-leveling of the surface-base. For this purpose, you can use either a traditional concrete screed( wet), or do without dirt, water and do not spend several weeks waiting for the full hardening of the surface.
The use of a dry screed, in addition, due to its low weight, allows to level the floor even in those houses where it is undesirable to increase the load on the bearing floors, and also in a dry screed it is easy to install parts of the heating system and lay the necessary communications. In addition to all the positive qualities, the screed is dry - it is a heat and sound insulating material of excellent quality, and its laying with your own hands is possible at any air temperature and time of year.
What is a dry screed
A dry screed is a bulk material of different fractions, which is covered with a thick layer on a previously prepared rough floor or on the lag of the dismantled floor. On top mount plates from gipsovolokna( GVL) or other material. The number of layers can vary from one to several. On the perimeter of the room, it is necessary to lay a damper belt.
How to start laying of dry screed
First of all, you should prepare for work surface overlap.
- - We dismantle the old floor covering.
- - Existing gaps and slots between the slabs and the walls are closed with a solution of cement and sand. Optimum use of cement grades above 150.
- - Remove debris and dirt from potholes and mounting depressions.
Mounting of the moisture-insulating material
The flooring on the prepared surface of the roughing floor of a polyethylene film, paper impregnated with bitumen or pergamina is a mandatory step. If neglected, the resulting condensate, vapors or the first leakage will lead to swelling of the dry backfill and the appearance of defects on the surface of the floor covering.
- - Prepare the moisture-proof material( thickness is chosen over 250 mk), cutting it into strips with the expectation that the protrusion of the film on the wall will be about 20-25 cm.
- - The edges of the film layers must overlap, fix them with adhesive tape.
Laying the noise insulation material
Most of the sound waves in the room penetrate the solid elements of the building( that is, the walls).Therefore, it is very important to lay a layer of tape zvkokoizoliruyuschey( foam polyethylene or glass wool or tape of mineral materials) about a centimeter thick around the perimeter of the walls adjacent to the screed.
In addition to sound insulation, this tape( damper tape for floor screeding) compensates for the increase in volume that occurs when the temperature rises.
Selection, backfilling and leveling of bulk material
For dry screeds, use granular, uniform granular materials. They should have the following properties:
- - incombustibility;
- - ability to retain heat well;
- - lightness;
- - very small shrinkage.
Suitable for dry screeds include: fine-grained slag, sand, and also waste that remains in the process of expanded clay production( it is unacceptable to use claydite in its pure form).
Open the bags and cover the selected material with a film. The thickness of the layer is not less than two centimeters. With large unevenness of the floor, the layer can be increased to 6 centimeters. If the layer needs to be made even thicker, it will be necessary to strengthen it with an additional layer of plates. The thickness of the screed is taken from the highest point on the rough surface. To do this, use the laser level and tape measure, making markings on the walls - a flat horizontal line for the convenience and accuracy of the work.
To this stage in the room, all work on testing and installation of heat systems and electrical wiring should already be completed.
To flatten the bulk material, it is necessary to apply U-shaped metal profiles. They need to be laid in parallel rows from wall to wall. It is important to check their horizontality by the construction level.
In order not to damage the screed and not to break its smooth surface, we put several wide boards on the backfill to move along them during the installation of the next layer.
Laying slabs GVL
Under the slabs or floor elements suitable for dry screed, understand: gypsum-fiber sheets moisture-proof( GVL), wood-particle boards( ordinary or sheet piling), moisture-proof plywood, sheets of asbestos-cement or expanded polystyreneplates. A distinctive feature - the presence of a special chamfer at the edges of the plates for installation.
The stowage is made from the door if the slabs are laid on a loose mixture, or from the opposite wall, if the base is heat-insulating slabs.
If the walls of the room have protrusions in the form of columns or outstanding angles, cut out exactly along the contour of the plate, pressing them firmly against the wall, completely eliminating all gaps.
Do not strongly press the plates into the backfill. Next, we apply a glue to the chamfer.
We lay the next floor element and in steps of five centimeters at a right angle screw the screws( screws), putting them 1 mm into the material of the plates. This will ensure sufficient strength of the connection and eliminate the appearance of cracks during the operation of the floor covering.
It is imperative to check the level of the floor horizontally during the entire assembly of the dry screed.
If the decorative coating requires increased strength of the base( for example, piece parquet), then 1-2 more layers of sheets of GVL should be laid. Installation is similar to the first layer, between each other, slabs should be smeared with building glue.
After completing all the work, we cut the protruding edge band around the perimeter of the room, produce the putty of the screw heads and proceed to laying the decorative coating.
Cost of materials
Knauf floor elements( in the package of 5 pieces 1200x600x10 mm): 280-300 rubles per packing.
Building glue( depending on the brand of the manufacturer and the volume of packaging): 50-550 rubles.
Dry backfilling for the floor of COMPEVIT( packing in bags of 40 liters): 180-205 rubles per 1 bag.
Ribbon edging in rolls: 300-350 rubles per roll.
Polyethylene film 100-150 mk: 10-48 rubles for sheets 1,5х2 meters.
Screws( packing 1000 pieces) Knauf: 300 rubles.
Guide profiles KNAUF( length 3 meters): 75-114 rubles.