Screed floor with claydite own hands

One of the basic requirements for any housing, be it your own house or apartment - warm , comfortable microclimate in it .And it is impossible to solve this problem only by the heating system. Whatever the powerful stand-alone boiler or central heating radiators, without the reliable thermal insulation of the rooms the desired result is not achieved.

In order that housing become invulnerable to the vagaries of the weather and in winter and summer , , should be practically insulated by all its elements - walls and shelves, windows and doors. But the floor is always attached increased attention - especially it is important for owners own homes and tenants of lower floors, under the apartments which are unheated rooms. The cold floor in winter is a feeling of constant discomfort, a direct path to the illnesses of people living there, plus a permanent huge loss of thermal energy that invariably affects the family budget. How to solve this problem? There are many options, and one of the most effective is a floor screed with expanded clay with your own hands.

Why choose claydite, what types of screeds are applied to it, how complex they are in independent execution - these are the issues of this publication.

Basic properties of expanded clay

Even , while in building stores presents many modern insulating materials on mineral or synthetic basis, claydite remains extremely sought-after material due to its versatility, environmental cleanliness and excellent performance.

What is this material? It is obtained by the technology of special processing specially selected varieties of clay. Raw goes through drying, grinding, thorough cleaning of impurities and organic residues - this is very important for obtaining really high quality ceramsite.

Then the prepared clay is bred to the required consistency, and granules are formed from the obtained mass in special drums, which are subjected to high-temperature roasting( of the order of 1100 ÷ 1200 degrees).Such a sharp thermal shock contributes to the effect of the - pyroplasty explosive gas ( account for the water vapor and thermal decomposition products of some of the raw materials), followed by rapid solidification to obtain a strong porous structure.

At the exit from the processing line, granules of red-brown or yellowish-red color with an external fused crust are obtained, which to a certain extent protects the clay from penetrating into its porous structure of moisture.

As you can see, no chemical additives are used in the manufacture of expanded clay, and if the manufacturer uses the really high-quality natural raw material , without the addition of industrial waste( eg slag), the material is absolutely clean from the ecological point of view .

In addition, the expanded clay has still a number of positive qualities:

• Material, for account porous structure, has excellent insulating qualities. The coefficient of its thermal conductivity, depending on the grade, lies in the range from 0.07 to 0.16 W / m × ° C .
• However, the material has a sufficiently high mechanical strength - depending on the density, it lies in the range from 0.6 to 5.5 MPa .

Claydite grade by bulk density	Highest quality grade keramzit	First grade ceramic grade
Strength grade	Strength limit, MPa, min	Strength grade	Strength limit, MPa, min
M250	P35	0.8	P25	0.6
M300	P50	1	P35	0.8
M350	P75	1.5	P50	1
M400	P75	1.8	P50	1.2
M450	P100	2.1	P75	1.5
M500	P125	2.5	P75	1.8
M550	P150	3.3	P100	2.1
M600	P150	3.5	P125	2.5
M700	P200	4.5	P150	3.3
M800	P250	5.5	P200	4.5

M is a mark of bulk density. For example, the M450 corresponds to 450 kg / m³

• Claydite is absolutely non-combustible material. When exposed to a flame, it does not emit any toxic substances that can harm the human body.
• Material is not a nutrient medium for microbiological life forms. In addition, claydite becomes an insurmountable obstacle to rodents.
• In addition to the high insulation qualities, it should be noted the ability of expanded clay to noise absorption - it becomes an excellent soundproof material.
• Claydite, despite on , that still absorbs moisture, is absolutely not subject to rotting processes.
• The material is not afraid of temperature changes in a very wide range - its insulation qualities from this do not change.
• In addition to all of the above - the material significantly benefits in its cost from many modern - heaters, it is available almost to all average consumers.

In sale keramzit comes in various forms. As a rule, at enterprises the main type of products is a large gravel with granules from 20 to 40 mm. When sorting, smaller fractions are eliminated - so claydite rubble is obtained with grains from 5 to 10 mm. Smaller wastes and disintegrated granules are crushed to produce expanded clay sand( 0 ÷ 5 mm) or sand-gravel mixture( 0 ÷ 10 mm ) . All these types of material, nonetheless , find its wide application in construction in one or another quality. True, their physical and operational characteristics are already somewhat different.

Parameters	Expanded clay gravel 20 ÷ 40 mm	Expanded clay aggregate 5 ÷ 10 mm	Expanded clay sand or sand and gravel mix 0 ÷ 10 mm
Bulk density, kg / m³	240 ÷ 450	400 ÷ 500	500 ÷ 800
Thermal conductivity coefficient, W / m × ° C	0,07 ÷ 0,09	0,09 ÷ 0,11	0,12 ÷ 0,16
Water absorption,% of the volume	10 ÷ 15	15 ÷ 20	no more than 25
Loss of mass,%, with freezing cycles( with standard frost resistance F15)	no more than 8	no more than 8	not regulated

Obviously,the than qualitatively expanded clay, longer than his faction, the lower the bulk density and higher insulating ability. However, the use of large granules in some cases is simply impossible due to the peculiarities of technology, the device of the sexes - this will be described below.

Sometimes can meet the claims that the claydite creates certain radiation background. It can be answered that if the material is manufactured by enterprises with an accurate standstill of GOSTs, then it is absolutely safe, and its specific active efficiency( AEFff ) should be within 200 ÷ 240 Bq / kg, with an allowable sanitary norm of 370 Bq / kg. But if you purchase the material of absolutely unknown origin - caution does not interfere. In any case, it is always necessary to ask the seller what type of keramzite is produced, and whether there is a necessary quality certificate for it.

Why you need floor screeds with expanded clay

These physical qualities of claydite make it sometimes irreplaceable for floor screeds.

• In private construction, when the floors in the country house are settled directly on the ground, this material does not have any competitors at all - it will allow to raise the level to the required level and provide the appropriate thermal insulation from the cold coming from below.
• In the same way, if it is required to insulate the floor, the base of which is a reinforced concrete slab, under of which the does not have a heated room.
• The clay using claydite becomes a reliable sound barrier, if from below, for example, there is a constant source of noise.
• With large differences in the level of the base surface, the claydite allows to save very much on building materials - a thick screed with expanded clay is incomparably cheaper than pure concrete. In addition, the preparation and filling process takes much less time.
• Due to the fact that the material is light , the screed with expanded clay will not exert an excessively high load on the slab.
• Under this screed it is possible to place engineering and electrotechnical communications.
• claydite-concrete screeds are very widely used in the arrangement of "warm floors".They become not only a reliable base for laying out the contours of pipes or heating cables, but also an effective thermo-insulating cushion, without which most warm floors can not do without.

Would you like to build a " warm floor" in the room?

It will be effective only if all the requirements for thermal insulation of its base surface are met.

More information about the warming flooring technologies, water or electric , read in the special publications of our portal.

There are not many drawbacks to the screed with expanded clay.

• The first of these concerns mainly , those screeds that are built using the classic "wet" technology. Speech goes that when the arrangement of such coverage, the floor level rises substantially - usually at least 100 mm. It is clear that far from all rooms this is possible simply because of insufficient height of ceilings.

• The second drawback is inherent in the floors with the so-called "dry screed" with expanded clay. Unfortunately, such coatings do not differ in water resistance - spilled water, if it managed to penetrate the into the thickness of the expanded clay layer, will not come out of there, and to eliminate this "damp center", the will have to dismantle the .

And now we will pass to the consideration of the basic technological receptions of for creating floor screed with expanded clay with our own hands. As already mentioned, there are two basic approaches - pouring "wet method" with those or other variations in the sequence of work, and backfilling the "dry hoe" with the subsequent flooring on top of the sheet material.

Pouring of screed with expanded clay ""

This method is applicable, in addition to the high leveling of the surface, needs to be given a semi-additional sound - and thermal insulation qualities, while not allowing too much load on the slab. Well, it is suitable and for the device of the insulated floor on the ground( provided that the concrete base with the primary warming layer has been already filled in, which is also widely used the same expanded clay).

Schematically "wet" screed with expanded clay can depict with the following image .

1 - slab or roughing screed on the ground.

2 is the wall of the room.

3 - waterproofing layer. Claydite, as it was seen - a sufficiently hygroscopic material, and that it does not absorb moisture, capillary coming from the ground or in the form of steam - from the premises from below, the hydro - layer of vapor barrier is a prerequisite.

4 is an elastic damper belt, which is used in modern technologies with the majority of screeds. It compensates for the temperature expansion of the resulting concrete slab, preventing the from its deformation and fracture.

5 - a layer of expanded clay, a thickness of at least 50 mm, and if you want to insulate the floor of the first floor or in a private house, then the minimum thickness reaches 100 mm.

6 - a system of beacons, predetermining the level of the floor being created. On the diagram, is not clearly shown, but together with the beacon system and reinforcement of the upper screed are most often packed.

7 - cement-sand screed, which will become the basis for further laying of the finish coat or floor heating system.

Now - specifically to the technology of laying such a screed.

Preparation of the

floor surface. Any screed must be angled on a carefully prepared surface. No excuses about that all is equal to layers of expanded clay and concrete will hide all defects , absolutely unjustified .Ground defects left at the beginning of the work can then appear already on the finished finishing floor.

• First of all, the state of the surface is checked. If there is an old screed on the floor, then it must be ensured that it is stable, without detachment, of the areas of erosion of concrete, its crumbling and , the .And in general , since it is planned to insulate the floor with a thick layer of expanded clay, the wisest decision will be to from the old screed, dismantling its to the ground.

This work is certainly not the most pleasant and light , but armed with a puncher, the owner will solve several problems at once. Building garbage immediately endure, so that it does not interfere with further operations.

• After a thorough cleaning of the debris, it is worthwhile to carefully inspect the exposed surface. If there are slots with a width of more than 1 mm, then their should be partitioned for of the subsequent filling with a repair composition. If oiled areas are detected, they are cleaned up to pure cement.
• Then, all areas requiring repair, are dust-free and treated with a deep penetration primer to achieve the required adhesion with the repair composition.

In its quality, a conventional cement-sand mortar can be used, but it is better to purchase single-piece - or a two-component filler( or sealant) on epoxy or polyurethane base - and the repair will be better, and hardening will pass faster, and for waterproofing repaired by the site you will not have to worry.

. All the cut slots, potholes, are filled with a spatula under the basic level of the floor .

After the has been conditioned with the repair composition instruction for the complete polymerization, the entire floor surface after regular cleaning with with dusting is recommended to be twice primed with a deep penetration compound. After complete drying, the surface can be considered ready for further work.

"Zero" Level Spacing

The surface of the floor is prepared - it is repaired, cleaned, dust free. But before the proceed to further installation work, you should immediately decide on the height of the future screed. In a word, it is required to beat off the "zero" line, outlining the level at which the will have the top layer of the coating created.

The easiest way to do this is to use the laser level - it will very quickly and accurately map the necessary lines on the walls. However, it comes from the fact that the given article calculates for people who are doing this for the first time, and they do not have such tool , and it is hardly advisable to purchase it for one-time work. Easier to buy the simplest water level - the accuracy of the markup from this will not be affected at all.

In addition, you will need a building level, a long metal ruler( for example, a rule), a pencil or marker, a tape measure.

• To begin with, the highest point in the room is determined approximately visually. Further markup will go from here.
• Perform accurate marking of the hydraulic level directly at the surface of the floor - it is very difficult, and sometimes impossible, therefore the first baseline is best carried out at a convenient height - for example, you can take 1500 mm from the ground floor level. At this altitude, a mark is placed on the wall with a marker.
• Then, using the water level, this height is transferred across all walls around the perimeter of the room.

The property of communicating vessels, , are capable of performing this with the utmost precision.

• The marked ( shown by the wide red arrows) are connected by a straight line - so the reference line is obtained, which is strictly horizontal( the diagram is shown in blue).
• From this line approximately about every me m tr heights are measured from the floor surface level( black curve line).The values ​​are transferred to drawing or even simply written in pencil on the wall at the point of measurement.(on the diagram - green arrows with corresponding inscriptions).Such measurements will help to determine with accuracy the highest point in the room.
• Now it is necessary to put a "zero" level. Let's assume that the total height of the screed with claydite is planned to be 130 mm ) 100 mm - insulation layer and more 30 mm - cement-sand screed itself. At the highest point, a simple calculation is performed. For example, the height from the floor level to the base blue line is 1500 mm. Hence, the distance between the baseline and the "zero" level will be 1500 - 130 = 1370 mm. From the baseline strictly vertically makes a measurement at the calculated distance, is put at risk.(the height of the coupler is indicated by the blue arrow )
• The same marks with the computed height 1370 mm are made at all other points of the measurement. As a result, we get a chain of marks, after which the line on the wall will perfectly match the exact line of the "zero" level( in the diagram it is shown in red).
• After the line is applied, it is worthwhile to perform another one important check. It is necessary to stretch the cord over the made mark across the room in several places, and check the height from it to the floor in the center of the room. It is not often, but it happens that there is a "hump" in the center of the room, and the height of the screed on this site will be less than planned. If you had to deal with such a circumstance, then will have to raise the common zero level to the required height.

Now you can proceed to the next steps.

Laying of the insulation layer and filling couplers

The next step is the hydro - vapor barrier of the base floor surface. The main task, as already mentioned, is to prevent moisture from entering the claydite layer from below( capillary or in the form of water vapor passing through the floors).

• If the floor is equipped in a private house on the ground, then it is worthwhile to make good quality insulation from roll materials like ruberoid. It is best to lay it in a "hot" way for bitumen mastic, carefully gluing the on the whips of adjacent strips( at least 100 mm).The waterproofing layer must necessarily climb onto the walls on the level above the of the planned screed.

In the event that the screed with expanded clay will be poured on a concrete slab, this measure may be excessive - it will be quite dense polyethylene film with a thickness of at least 200 microns. Cloths are stacked overlapping each other in 150 ÷ ​​200 mm, and must be glued in these places with waterproof construction tape. The film should also go over the walls above the level of the future screed.

• If you plan to leave some communications under the coupler, then they should be immediately prepared for this. The cables must be hidden in the plastic corrugated tube , the pipes are hermetically wrapped with the polyethylene film .
• The next step is to strengthen the damper belt around the perimeter of the room, which will absorb the thermal linear vibrations of the screed.

Acquire damper tape with calculation so that its width was greater than the height of the planned screed - the projected surplus after the end of the work will be easy to cut.

Attach damper tape with so that the wall edge of the waterproof film is underneath it( see diagram above).The can be fixed in different ways - on an existing self-adhesive layer or with pieces of adhesive tape. The main thing that it was laid on all vertical surfaces - walls, openings , niches, columns and , .

The next step, it would seem, should be the installation of a lighthouse system. However, the further course of work may differ somewhat.

A. You can proceed as follows.

• For all waterproofed the floor surface is covered with expanded clay( is the best used , from 10 ÷ 20 to 20 ÷ 40 mm - it also has less dust and has warmer qualities).The backfill layer is selected with the calculation of the to leave space for the concrete screed from above, at least 30 mm. When filling, it is necessary to compact the expanded clay, for example, compacting it with a wide plastic or wooden plaster grater .

• This thermal insulation layer is then spilled with cement ( cement "molochkom") with a liquid solution of and left for a day so that the claydite granules communicate with each other and they can be moved for subsequent operations. Another option is to "redeem" the expanded clay in advance in cement milk in a concrete mixer, and then spread it on the floor.
• After layer of heat-resistant expanded clay filler finds certain strength, it is possible to lay the reinforcing mesh and expose guides - beacons for pouring screed. Here it is necessary to make some important observations:

- Serious error is made by those who lay the reinforcement belt close to the bottom layer. It turns out that the grid takes little part in, in fact, reinforcing the screed - it's like " is stuck from the bottom, and often some of the bars are not even completely immersed in the solution from all sides. It will be optimal to place on its so that it falls roughly in the center of the future concrete shoe. To do this, you can apply pads of pieces of concrete, ceramic tiles and t ., Or purchase special plastic racks that will raise the reinforcement to the desired height.

- Guide rails are most often made of plaster galvanized profiles . In our case, it is not possible to apply the technology of installing beacons with the help of self-cut screws, adjustable in height, simply .Hence, the best option would be fixing them on the slides of the mortar. And here some "masters" who are trying to speed up the process, admit another one mistake, using building mixtures based on gypsum. Yes, they of course freeze and fix the beacon in the given position very quickly, but that's only the quality of the screed from this seriously will suffer.

The fact is that the physical characteristics of cement and gypsum - very seriously differ - for water absorption, strength, linear expansion, shrinkage degree and , .Hence, the construction of the screed is not uniform, and then it will not be necessary to be surprised that along the lines of the lighthouses I will go t t of the river. Ideally, slides for fixing beacons should be made from the same solution as the screed will be poured. It's okay, one day you can wait and get a good result.

The beacons are set strictly according to the previously planned "zero" line, their horizontal and alignment in one plane is carefully controlled with the help of the building level. The distance between adjacent guides is selected with calculation of so that the on the with is free to rule, with a margin of at least 200 mm on each side of the - for lateral movements when leveling.

• After the system of lighthouses has received sufficient stability, go to the filling screed. To do this, you can prepare a conventional cement-sand mortar( 3: 1), which is desirable to "fertilize" a special plasticizer sold in the building store, and fiber-optic micro-reinforcement. If there is a financial opportunity, you can purchase a ready-made building compound for screed with an already balanced modified composition.

• The screed is poured in the usual way - the finished mortar is laid out between the guides with a slight excess. Take measures to ensure that there is no air void - is carried out distribution using a spatula or trowel, with piercing the mass to exit the air bubbles. Particular attention to areas along the lighthouses and reinforcement bars - the solution must fill all possible cavities. Then the final alignment of the screed is carried out with the rule for the beacons.

• After the screed is completely filled, its is left to set. Then, after 10 ÷ 12 hours, to avoid drying and cracking, it is advisable to moisten the with its water and completely cover with the polyethylene film .If necessary, moisturizing can be repeated periodically.
• After about a week, the screed can be safely moved. In the same period, the upper edges of the polyethylene film and the damper tape protruding above the are cut. But here further construction and finishing work is too early to begin - full maturation of concrete will come only after a month. However, if modified mortars for screeds are used, the term may be less - this must be indicated on the package of the composition.

B. The second method is somewhat different. By this method, the lighthouse and reinforcement system is installed immediately, on the waterproof surface.

• Two mortar posts are required:

- One( for example, a concrete mixer) prepares a thick mortar of cement, sand and expanded clay in a ratio of 1: 2: 3.In this case, at first keramzit is buried in the water, in order that it absorbs the necessary amount of moisture. Then, during the mixing , the required number of remaining components is added. The composition should be "tight" - plastic enough for leveling, but not spreading when laying out.

- on the second post ( for example, using a hand-held electric mixer) a mortar is prepared for the floor screed itself - cement-sandy or from a ready mix.

• With this technique, the of both layers is stacked stepwise. Initially, the concrete-expanded claydite solution is laid out for a section up to width 1 m - so that you can reach the rule.
• After leveling this layer and leaving approximately 30 - 40 mm from the level of the beacons, immediately lay out the screed composition and align it along the guides. At the same time, about 150 - do not reach 200 mm to the edge of the first layer.
• Next, the operation is repeated: claydite-concrete layer - and after itself the screed.

To be honest, this approach does not look optimal. First, there is no need to expect a large win over time, compared to the with the first method. Secondly, we need a very good coherence of workers who are simultaneously preparing two different solutions. And thirdly, the insulating qualities of the resulting "pie" will still seriously give way to the first option.

B. Finally, the third way to fill screed.

In this embodiment, the entire pouring layer, from the base and up to the upper level of the of the beacons , consists of a concrete-expanded clay mortar. It would seem that everything is simple and convenient, but this is not entirely true.

• Ceramsite is much lighter than water, so in the solution it will always tend to float to the surface. This means that to straighten the screed, as with conventional concrete, hardly will turn out - it all will remain bulky and rough.

• The second minus. Granules or particles crushed expanded clay , used as a filler, in their strength properties are much inferior to quartz sand. And this means that the surface will not be so strong - it will be characterized by looseness and increased dust formation.

To some extent, such a drawback can be minimized by grinding the top layer and impregnating it with special hardening compounds - and are extra material and labor costs. Another option is to pour a layer of self-leveling composition over this screed, which will also require additional costs.

But if such a floor is planned to be used as a basis for laying ceramic tiles, this will be a very good solution. In the given case, neither the roughness nor the reduced surface strength of the screed with expanded clay is of decisive importance.

In the rest, the screed is poured using the same technological techniques as described above.

"Dry" screed with expanded clay with its hands

This is a relatively new technology arrangement insulated floors with expanded clay, which rapidly conquers popularity in our time. Such coatings have a number of advantages compared to "classic" ties - this will be discussed below. And for starters - a basic circuit of their device:

1 - concrete floor base, 2 - wall of the room.

3 - a layer of waterproofing is required - a usual dense polyethylene film .

4- damper tape, laid on the entire perimeter of the room.

5 - compacted and leveled layer of dry fillings on expanded clay, at least 30 mm( optimally - up to 60 mm).

6 - finished floor elements made from gypsum-fiber plates( GVL).

7 - self-tapping screws that connect the floor elements to each other.

The resulting coating becomes the basis for laying almost any finish of the floor.

The scheme is uncomplicated, but it has already proved its effectiveness and convenience:

• No such equipment is required to lay this screed - everything is done manually.
• Completely no "wet" work cycles. The rooms are not diluted with dampness and dirt, which are the inevitable "satellites" of any other technologies for laying the screed. This gives the the opportunity not to move out of the apartment while the repair is being carried out - the screed can be stacked sequentially, only measures are taken to protect the rest of the premises from dust. And dust from expanded clay is not so is allergenic to , like from that of the same cement.
• The total weight of this screed is much lower than concrete, which is very important in multi-storey houses. In addition, it reduces the cost of transportation and delivery of material to the apartment.
• The screed does not require a long period of hardening and hardening - right after the its stacking can proceed to further operations. And is a very significant reduction of general repair terms.
• That that the backfill of the is not bound by the cement, does not at all say that the is fragile. Correctly mounted dry screed can withstand static loads( for example, from furniture) to 1 ton per square meter, plus dynamic - more not less than 400 kg. On such a cover it is quite possible to arrange light interior partitions, for example, from plasterboard or plywood.

Would you like to have a partition in a spacious room?

The floor, covered with a dry screed, will not become an obstacle to this if the correct design option is selected.

Read more about how partitions are built in room - in the corresponding article of our portal.

• This coupler gives the a very sensitive insulation and soundproofing effect.
• In a thick dry screed, it is very convenient to place hidden communications - cables or pipes.

There are, however, some limitations on the use of dry screed technology:

• Very hard it will be performed in too tight rooms.
• Do not apply a dry screed there, where assumes permanent dynamic loads ( intensive movement of people) or where can vibrate from installed equipment( washing machine, for example, is not recommended for such a floor).
• It has already been mentioned that it is inadmissible for rooms with high humidity or where a large amount of water can be spilled onto the floor.
• The dry mortar assumes an exceptionally horizontal level. If the room for any reason requires a slope, then such coverage is not applicable.

Accessories for dry screeds and necessary tools

So, the basic materials and components for arrangement of dry screeds are waterproofing film, damper tape, dry bulk claydite composition, GVL floor elements, self-tapping screws and glue for their installation.

On the film and the tape does not make sense - they are no different from those used for the usual screed, which is described above.

Composition for backfilling of dry screed

When searching for materials for dry screeds, it is best to orient to ready systems, represented, for example, by the company " Knauf ". Its kit "Vega" was created with the calculation for living quarters.

If not, then will have to purchase all the components separately, and with special attention to the selection of dry backfill.

• The unconditional leader in quality is the backfilling " Compavit ", the bulk of which is produced in in Belarus . her is very well matched granulometric composition - claydite fraction is sustained within 1 ÷ 4 mm, practically there is no dust component. The granules are neat, with rounded edges, which allows the t t to thoroughly compact the backfill with its alignment.
• The Belarusian filling "Kerafloor" , which differs little in quality, also renders quite worthy competition.
• Strange fact, but for some reason masters do not particularly praise the backfill, which is realized under the trademark " Knauf ".It is clear that this is a product of licensed production, but all is equal - and the uniformity of the pellets is not the same, and dust is much larger. In any case, experienced builders will take the same " Compavit ".
• Composition under the brand « RDS », alas, still worse. In , is likely to use claydite production waste after crushing, since the percentage of dust-like component is high, the granules are heterogeneous with sharp edges.
• There are on sale and completely incomprehensible backfills, in which in general is not specified by the manufacturer. These are obvious wastes, which are realized in this way. If you use such compounds, you can face a very heterogeneous shrinkage of the buried layer, strong dusting, difficulty in leveling and , .In short, for a little money you can get big problems.

The amount of backfill to be purchased is calculated from the area of ​​the room and the thickness of the screed . For convenience, packages with claydite composition are marked in liters( dm³).Do not make an independent calculation t t ore anyone familiar with the school course of mathematics.

Video: advice on choosing backfill for dry screed

GVL floor elements

Although is imposed on on a large , dry liners can be made from many sheet materials( plywood, gypsum board, OSS ), the most convenient are of course the finished two-layer elements made of gypsum-fiber board. They are ordinary( GWL) and waterproof( GVLV).

The main advantage of these is that they already have an optimal thickness of 20 mm and are equipped with special locking areas - with lamellae, which simplify the process of with GVL bunkers to a single design.

Standard dimensions of the floor elements " Knauf " - 1200 × 600 mm. On sale, you can also find panels 1500 × 500 mm.

GVL is very easy to cut, for example, with a jigsaw or manual circular, but with have high surface strength, easily withstand significant loads.

Usually, the floor elements are purchased with 15% with a stock of from the area covered by them.

Adhesive and screws

For bonding of laid floor elements, glue and self-tapping screws are used.

• With glue it's easy - it's the most common PVA .Its consumption is low, so that a kilogram should suffice, for example, for 20 m² of covered area.

• And for final fixing of sheets it is better to use special self-tapping screws " Knauf " for GVL.They are distinguished by two-way thread, very sharp piercing sting and self-heating countersink head.

It should be guided by the fact that will take about 12 self-tapping screws per square meter of covered area. They are usually sold in batches of 1000 pieces. Their cost is low, so it is better to buy with a margin - they are always useful in the household.

Tools for working

• One of the key moments is the installation of guides for leveling the loose component of a dry screed. And here it is necessary to make a very important observation.

If the reader gets an article about a dry screed, where the creation of a system of beacons according to the type of "classical" filling is painted - with stationary guides immured in slides of mortar or installed on self-tapping screws - let boldly close this page. Such an "author" has no idea about a dry screed, does not understand its device in , and simply rewrites it when the error is made before it. Never, under any circumstances, guides in a dry screed can not be stationary - they are used only for the leveling process and then, before the flooring of the sheets, they are necessarily cleaned.

The dry screed only in this case will show its advantages if the floor elements are laid tightly, with its entire surface on the leveled backfill. If you leave the guides, then when the mixture shrinks( and from this you can not escape), the sheets will lean on them, cave in, deform, there may be cracks, and the floor creak will be provided for 100% .

1. As temporary guides, it is most convenient to use ready-made kits, which include the aluminum profiles themselves plus the rule. The shape has been developed so that when moving along the guide its groove surface falls on their lower edge.

It is very convenient - once the backfill is leveled, the guides are removed - and a smooth, leveled surface ready for GVL flooring is immediately obtained.

2. It is clear that such kits are only for professionals. It's okay, you can do galvanized profiles of 60 × 27 mm. They can be used in two ways:

	The preparation of the floor surface differs little from that already described above. Minor repairs are carried out, cables and pipes, if any, it is desirable to fix the clamps to the floor. There is one subtlety - if the wall surface near the floor is too uneven - it makes sense also to repair it, at least to the level of the screed. Otherwise, subsidence is not excluded in these places.
	In this example, the bottom of the room is a warmed dry room, so the craftsmen did without polyethylene film. However, it is better not to neglect it - there is a film inexpensive, and it will not take much time for its flooring. The next step is to install the edge damper tape.
	It can be fixed in different ways - in this case it simply presses against the wall with long slides of a backfilling expanded-clay mixture.
	Next, along one of the walls is a shaft from the backfill on which the guide is laid.
	Adding a "compute" profile to the profile or, on the contrary, removing its excess, the guide is exposed to the required horizontal level. At the same time, it is taken into account that 20 mm more "will take over" the elements of the floor GVL. You can orient yourself either by laser level, or by marking the zero level made on the wall.
	At the distance of the existing rule in the middle of the room another shaft is poured - for the second guide.
	Installation of the second guide is carried out in a similar manner.
	When both "beacons" are installed, a dry compound is placed in the space between them in a somewhat excessive amount.
	The backfill is compacted with some available means, and then leveled with the rule, moving it along the established profiles.
	After leveling, the profiles are very carefully removed and moved further along the work progress. Minor flaws immediately smoothed. The result is a flat surface.
	You can fall asleep and align the entire area of ​​the room immediately. Some masters prefer to work by stretching, alternating filling and leveling with the installation of floor elements.
	You can proceed to install floor elements. Scheme of their laying master is free to choose himself - from the far corner to the exit, working "for yourself", or vice versa - from the entrance to the room to its far edge - from yourself. The main thing is that the floor elements lie down "in the dressing."
	If the installation is carried out from the far edge, then island bridges from sheets of GVL are suitable for moving around the floor. The laying starts more often with a corner, for which the first part is cut from one side with a lock part with lamellas. After laying the element, the lamellas from the two docking sides are abundantly coated with PVA glue. Then another sheet is laid, carefully combining the lock parts. In doing so, be sure to ensure that the slats do not hit the grains of backfilling - they need to be swept away immediately.
	as necessary, the sheets are cut to the correct size, always taking into account the correct location of the slats.
	Installation is carried out in the same order and further.
	Having laid two rows, it makes sense to immediately fix the floor elements together with self-tapping screws. The distance between adjacent fasteners is about 150 ÷ ​​200 mm. The heads of self-tapping screws should be lightly damped in GVL for 1 ÷ 1.5 mm.
	The work is carried out until the entire surface of the floor is completely covered. Do not leave the joints in the doorways - they need to be moved to the side of the corridor or room at least 250 ÷ 300 mm.
	After laying the last sheet the final fixation of the coating with self-tapping screws is carried out.
	It only remains to clean up - vacuum the surface of small debris, cut off the protruding damper tape, wait for the adhesive to dry completely - and the floor is ready for finishing works.
Illustration of	Brief description of operation

- By analogy with the professional kit. The profile is laid down by the transverse shelf downwards and is exposed horizontally so that its lower edge corresponds to the required level of the equalized backfill. To give the profile of gravity, it is possible to pour the expanded clay mixture inside it. For alignment, you need a rule with figured cutouts - for the "arm" master, do not represent t ore to cut it, for example, from a flat board or thick plywood.

- another option - the profile is placed with vertical shelves down and the is backed up in the backfill so that its horizontal level is at the desired level of alignment. In this case, further work can be carried out by the usual rule. However, after removing the guides, grooves can remain which will have to pour and gently level with the overall surface.

The rest of the tool, in principle, is for any home master. screws are needed rt for I screw the screws, shovel, scoop, spatula, trowel - for backfill distribution, some kind of improvised ramming, type hand plaster graters .You will need the SC for and the polyethylene , the construction knife, the level, the tool for , and the GVL cutting.

The process of installing a dry screed

It is worthwhile to briefly consider the step-by-step process of laying a dry screed :

It would seem that everything is simple, but at first, certain problems may arise when leveling the backfill surface. It does not matter - a dry screed is good and that is possible during work to eliminate flaws .Better, of course, to fix everything at once, so that after some time of operation it was not necessary to disassemble the construction to fix serious drawbacks.

Video: eliminating the consequences of incorrect mounting of floor with dry screed

AND still one issue concerning dry screed. Often asked questions - can it accommodate the pipes or cables warm floor? The answer is categorical - no, because the water or electric resistive warm floor necessarily provide for the presence of a monolithic concrete shoe that acts as a battery and heat exchanger. To heat a thermo-insulating layer of expanded clay is a completely useless occupation. True, there is a way out in this case too.

Is the dry screed compatible and warm floor?

With water and cable floor - definitely not. But with film infrared they have excellent compatibility.

About how calculate and independently lay film infrared floor - in a special publication of our portal.