The method of dry screed began to be used for a long time. It became very popular among professionals and amateur builders when special integrated material systems for various types of work appeared.
Knauf company gained wide popularity among builders. The floor elements of this manufacturer are an integral part of the complex for flooring. Their use makes the process of leveling and preparing the surface for coating very technological.
Gypsum board
The material GVL (gypsum fiber sheets) of which the floor element (KNAUF) consists is well distributed in the construction market. Cellulose fibers from waste wood or waste paper are specially fluffed and mixed with a gypsum binder. The resulting mass is wetted and pressed into sheets. After drying, grinding and cutting, boards with a thickness of 10-12 mm are obtained. So that the gypsum fiber does not stain hands and clothes, it is impregnated with a composition against chalking. The main advantages of GVL are environmental friendliness, fire resistance, the ability to absorb excess moisture, heat capacity and sound insulation. If you use water-repellent additives, GVL acquires moisture resistance.
The main disadvantage of GVL is severity, fragility during transportation and handling. Therefore, it is more convenient to use small-format GVL. Knauf makes floor elements from such sheets.
Description of floor elements
The panel for the prefabricated base - a floor element of KNAUF "Superpol" - consists of two GVL sheets 10 mm thick, 1200x600 in size. In the factory, they are glued together with a shift of 50 mm in two directions. As a result of the displacement, a fold is formed to assemble the panels into a single flooring. Through this fold, the elements are glued and screwed together with self-tapping screws.
The longitudinal edge of the sheets can be straight and inclined - seam, the end - straight.
Dry screed technology
The ceiling on which the prefabricated base is mounted can be concrete (monolithic or prefabricated from slabs) or wooden (with plank or sheet flooring). In any case, it is necessary to arrange hydro- and vapor barrier by installing a PVC film or any rolled material of the desired properties. The strips are laid with an overlap of 200-250 mm and a lap on the wall. This layer will prevent both the effects of leaks from above and the penetration of moisture from the ceiling.
Enclosing structures - external and internal walls - are separated from the future "pie" by a sound-absorbing pad: an edge tape made of foamed polymeric material is laid along the perimeter.
A layer of backfill is applied to the film, the minimum thickness is 20 mm. This layer forms a flat surface for laying panels and performs the functions of heat and sound insulation. For backfilling any material is used, consisting of granules of approximately the same size, a fraction of 3-5 mm, without dust and dirt. Expanded clay has the best quality . On the basis of it, specially prepared backfills for dry screed are prepared: Compavit, Keraflur, etc.
Leveling of the backfill is carried out according to the level of the floor, determined by a laser or hydraulic level. For this, it is convenient to use a special tool from Knauf: a set of temporary beacon guides and a rule. More often as beacons they use a profile for the installation of GVL.
Board of Professionals
Experts advise using beacons only to level the backfill and do not lay GVL floor elements (KNAUF) on them. A layer of bulk material will sag and compact over time, the panels will rely on metal, which will lead to noise and reduced thermal insulation of the precast floor structure. Therefore, beacons should be removed.
The fragility of the floor design without the usual lag seems. Carefully leveled backfill and correctly laid floor elements produced by Knauf have a very high load-bearing capacity.
They are laid on a flat surface with a break between the rows of at least 250 mm. To assemble the flooring, special glue is applied to the folds of the panels in accordance with the instructions. Then each floor element “Knauf” is connected with self-tapping screws 19 mm long, which are screwed strictly vertically, recessing the heads of self-tapping screws.
The last stage of the foundation device will be the putty of recessed self-tapping screws and seams between the GVL panels and the primer of the surface with a hardening compound. After that, the base of the floor is ready for facing with any finishing coating - both roll and piece.
Right choice
This method of preparing the floor has many advantages. This speed, convenience, independence from temperature conditions, increased sound and heat insulation. Dry screed is a very technological and intuitive construction process. It is not for nothing that it is believed that even a person who does not have experience can do such floors .
For the installation of prefabricated floors, other plate materials are also used: gypsum sheets, chipboard, ordinary and moisture-proof plywood. But only the floor elements produced by Knauf correspond most fully to this technology, greatly enhancing its positive qualities.