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Floorboard or plywood which is better. View Full Version : Boards or plywood for floors over wooden beams? Advantages and disadvantages

Dry prefabricated floor screed is most often made from plywood sheets. It is believed that this is an ideal base for any type of floor covering, including linoleum, laminate, carpet and even ceramic tiles. A high-quality and durable plywood floor on logs requires attention to the nuances and compliance with the basic rules specified in SNiP.

Plywood is a multilayer wood- sheet material, which is made by cross-gluing an odd number of layers of peeled veneer. For production, birch raw materials or coniferous species of technical grades are most often used, less often - oak, beech, linden and others.

Advantages of plywood:

• high mechanical strength to any load;
• relatively small weight;
• low coefficient of thermal conductivity;
• an acceptable level of humidity (8–12%), which allows the use of some types of plywood in damp and unheated rooms: kitchens, bathrooms, balconies, loggias, etc.;
• application in combination with systems "warm floors" of water and infrared type.

The downside of sheet material is that adhesive compositions that are unsafe for human health are used for production. As a rule, products are assigned an emission class of at least E1.

Plywood products are classified according to the following criteria:

Scope of application.

The fields of application of sheet material are endless - from construction to electrical engineering. But for the formation of a prefabricated screed or a finished floor, it is recommended to use structural and building varieties.

Mark.

This setting is determined by the type of adhesive composition. Consider three basic types:

• FSF (plywood glued with resin phenol-formaldehyde glue). The product is considered moisture resistant, it is used for finishing rooms with normal and high levels of humidity.
• FC (plywood glued using urea-formaldehyde glue). Refers to products of medium moisture resistance, recommended for use in dry rooms.
• FBA (plate on albumin - casein glue). Positioned as a material of limited moisture resistance.

Sort.

According to GOST 3916.1–96, the products differ in the number of permissible defects and flaws in wood, as well as the marriage made during processing. There are five levels of quality:

• E - extra or elite. The product is made of oak, alder, birch and other species, has a perfectly smooth, smooth surface, there are no slightest defects. A slight deviation in the structure of wood of a random type is allowed.
• I - pin and healthy light or dark knots are possible - no more than 3-5 pcs. per square meter of surface. Slots (except for closed cracks) and other types of marriage are excluded.
• II - healthy, partially intergrown, non-united and falling knots with a diameter of up to 6 mm, wood inserts and open cracks up to 200 mm long and not more than 2 mm wide are allowed.
• III - there are: a) wormholes and holes from fallen knots with a diameter of up to 6 mm in an amount of not more than 10 pcs. per 1 m² area; b) open cracks 300–600 mm long and up to 5 mm wide (provided they are sealed with fillers or sealants); c) dents and scallops.
• IV - a surface with all sorts of defects: from intergrown and fallen knots without limiting the number to defects along the edges up to 5 mm deep.

For a subfloor on logs, as a rule, sheet material of 1–4 quality grades is used. Please note: plywood is usually double marked, such as 1/2 or 2/2. Corresponds to the grade of each side. That is, a class 1/3 product is characterized by the fact that one surface is assigned category 1, and the second - 3.

The nature of the processing.

Sanded and unsanded plywood.

Plywood boards are either sanded or unsanded. Marked:

• Ш1 - processed only on one side.
• Ш2 - polished on both sides.
• NS - unpolished.

Laying the floor along the logs is carried out using plates of any kind. But common sense dictates that it is better to use products that have been sanded on at least one side. This will create the most even and smooth floor for the installation of linoleum, laminate, etc.

Dimensions.

The length of plywood sheets can reach 6 m, the width is 3 m, and the thickness starts from 3 mm. For rough and finish work horizontal bases applied material:

• 1525x1525 - the most commonly used size for the floor by joists. The amount of waste is small, easy to transport.
• 1210x2440 - for leveling bases in multi-storey buildings standard series having elongated rooms.
• 500x3000 - convenient in multi-storey or commercial new buildings, where the principle of studios or free planning is implemented.

The optimal thickness of plywood for the floor along the logs depends on the type of prefabricated screed and the level of load. If it is planned to install in two layers, then it is better to choose products with a cross section of 8–12 mm, and for single-layer installation - 8–22 mm.

Lags and fasteners

According to SNiP 3.04.01-87 (SP 71.13330.2017) "Insulating and finishing coatings" for the formation of the floor along the logs is used wooden beam chamber drying, humidity 12–18%, without cracks, bark and traces of rot. In this case, the length of the joined supports should be at least 2 m, the thickness - from 40 mm, and the width - 80-100 mm.

Although many experts recommend purchasing slats with an aspect ratio of 1:1.5 and 1:2, in practice, logs of 50x40, 50x50, 50x70 and more are most often used. Moreover, the height of the supporting elements depends on various parameters: the load level, the section of the insulation used, the maximum floor height and even the personal preferences of the customer. universal recommendations No, components are selected in each case separately.

For arrangement load-bearing frame in apartments and private houses, the most even, durable timber from inexpensive species is required: pine, spruce. If finances allow, then you can purchase products from larch, aspen, and alder that are resistant to moisture changes.

Don't forget that wooden elements structures do not have high biostability. Therefore, they must be treated with fungicidal and hydrophobic agents. This will significantly increase the life of the entire floor structure.

It would be useful to mention the lining elements under the logs. Building codes do not recommend the use of wooden wedges and bosses due to the fact that the material easily changes shape with changes in humidity. When mounting on a concrete or plank floor, mineral screed or point supports under a beam, it is better to lay hardboard strips.

In practice, many craftsmen prefer to lay pieces of OSB, chipboard, MDF or moisture-resistant plywood on the floor. The minimum size of the lining should be 10x10 cm or 10x15 cm, the interval between them should be at least 30 cm.

Laying the lag on glued plywood linings.

As an alternative, insensitive to moisture, you can use special anti-corrosion-coated support and fasteners designed for the installation of adjustable floors.

Consider another important component of the floor structure - hardware. In addition to the lag, you will need fasteners for fixing them to the base, as well as for attaching plywood sheets to the frame. These can be anchors, nails, universal or self-tapping screws, metal corners, etc.

The range of fasteners is huge. For fixing pads or directly to the lag concrete base dowels are most often used - nails with a thread with a diameter of at least 6 mm or metal anchors of a mechanical type. The former are cheaper, but the latter provide a more reliable and durable fixation of the rails to the base.

An example of fixing a lag to the floor with corners.

Anchor fasteners for concrete and brick are made of high-quality alloys - brass, stainless steel. It consists of a spacer or working sleeve (changes dimensions when a connection is formed) and a non-spacer part - a rod. To mount the frame to the base, a hole is drilled in concrete with a diameter equal to the section of the sleeve or 0.5 mm less than it. When hammering or screwing in, the mounting post expands the sleeve inserted into the channel. And due to this, it is firmly fixed in concrete.

The dimensions of the hardware product depend on the dimensions of the supports. For the installation of lining elements made of chipboard, plywood, OSB, as well as wooden logs, products of category M 6 are most often used. – M 12, that is, with a rod or wedge diameter of 6 to 12 mm. The length is selected based on the thickness of the lag and / or backings, taking into account the depth of penetration into concrete from 5 cm or more. The approximate interval between fasteners is 30–60 cm.

To rigidly attach linings or logs to a wooden subfloor, you can use wood screws with rare carvings or universal galvanized ones with a diameter of 4 mm or more. The distance between the hardware is at least 30 cm, the screwing depth is from 30 mm.
For attaching plywood to the logs, it is most convenient to use special self-tapping screws for GVL and chipboard or universal galvanized ones. The former differ from the standard ones in mixed screw threads and notches on the cone-shaped cap, which provide countersinking. The length of the hardware should be 2–2.5 times the thickness of the coating, the diameter should be from 3.5 mm or more.

For plywood on logs, it is not recommended to use black hardened wood screws. Practice shows that when seasonal changes geometric dimensions this type of hardware breaks under load, and the structure “loses” rigidity.

Ordinary nails with a cylindrical shaft and a sharp end can also be used. The efficiency and speed of work will increase several times if you use fasteners not in bulk, but in a cassette designed for nailer. The product is aimed at the base or the supporting frame often - at a distance of 15–25 cm.

Step-by-step instruction

For do-it-yourself installation of a prefabricated screed, you will need:

1. Plywood sheets of suitable thickness.
2. Legs are wooden.
3. Lining material for leveling the base.
4. Antiseptic primer.
5. Hardware.
6. Noise and / or thermal insulation with accessories.
7. Repair compositions for partial restoration of a damaged base.
8. Waterproofing.
9. Damper tape.
10. Silicone sealant or flexible wood putty.
11. Roulette, marking pencil, metal ruler or rail.
12. Drill / screwdriver or hammer / nail gun (nailer) with accessories.
13. Level laser or water.
14. Spatulas, brushes, rollers.
15. Cutting tool with accessories for wood and plywood (circular saw, jigsaw, etc.).
16. Grinder machine.

The technology of work on the installation of a prefabricated screed is partially presented in SNiP 3.04.01–87 (SP 71.13330.2017) “Insulating and finishing coatings”. In accordance with the recommendations of these standards, laying is carried out in 4 stages.

Preparation

Any repair begins with cleaning the base from debris, dirt and dust. It is advisable to remove oil, bituminous and similar stains, traces of soot and soot from the surface.

No professional will start work without partial renovation damaged areas. Rotting, damaged elements of the wooden flooring must be replaced, and cracks and loose areas of the mineral base must be restored. To do this, you need to embroider the cracks, remove dust and fill with repair compounds. If possible, it is better to clean off fragile sections, and smooth out the formed pits with the help of cement-sand, bulk and other quick-drying mixtures.

If necessary, the floor is waterproofed. It is needed if:

• it is required to protect the structure from the residual moisture of the concrete base;
• under the ceiling there is a cold basement;
• the floor on the logs is arranged in the bathroom and the room located on the floor below should be protected from possible leaks.

To create a waterproofing, the entire available range of materials is used: films, membranes, rolled glued products, coating compositions, paints and the like.

In some cases soundproofing of the base is required. According to the rules, the acoustic layer is placed between the base floor and the screed. Therefore, noise-absorbing mats are laid under the logs. If soundproofing mineral wool (stone or glass) is used, then it must be laid in the openings between the joists, and the support rails themselves should be fixed using point acoustic spacers.

Laying lag on acoustic pads.

It is desirable at this stage to treat the timber, bosses and other wooden structural elements with antiseptic impregnations.

Formation of a power frame

The log frame can be formed in the form of longitudinal beams or as a single or double crate. Of course, the second option creates a more reliable support for plywood.

SNiP 3.04.01–87 (SP 71.13330.2017) recommends laying slats across the light flux, and in corridors and other premises with a certain direction of foot traffic - perpendicular to the movement. Of course, in the future, the frame will not be visible under the coating, but the essence of the advice is different. The developers of the building code determined that if the frame is formed across the most intensive movement of people, then the loads will be distributed over most of the supports of the load-bearing frame, and not over 2–3 elements. Or worse, between them.

First of all, a zero mark is revealed, relative to which the supports are aligned. Further, beacons are mounted under the lag beam, or the required level is beaten off on the wall with a dye thread. But the most convenient way building a reference line - a laser level with a plane builder.

If sound insulation is required, before installing the supporting frame, it is necessary to lay acoustic material on the base: plates, membranes, rolled products.

Now you can proceed with the installation of the log in compliance with all the necessary clearances:

• Between the extreme rail and the wall - at least 20 mm.
• Between adjacent supports - from 30 cm, but not more than 50 cm. We remind you: the higher the load on the floor, the more often the logs should be.
• Between the ends of one row - 0–0.5 cm.

For alignment, under the frame elements, gaskets made of chipboard, OSB, MDF, etc. are installed. After checking with a level, bosses or lining boards are attached to the base dowel - nails, self-tapping screws or anchors.

Plywood lining.

Logs on wooden lugs.

To drill holes for hardware in backing components, logs and plywood, you should purchase feather or special wood drills with a countersink.

On firmly fixed supports, many craftsmen recommend laying damper layers. Such a preventive measure will not allow the structure to start creaking in the future.

The penultimate step is fixing the log over the entire area of ​​\u200b\u200bthe room using suitable hardware. Please note that in doorways a widened rail should be laid, which will protrude beyond the partition by 50–100 mm on each side.

For maximum leveling accuracy, you can use fasteners and support hardware designed for adjustable floors. In fact, these are powerful anchors that are installed in the floor slab. Adjusting nuts are screwed onto the main bolts, then a beam is placed and fixed with a lock nut. The excess anchor rod is cut off with a grinder or a metal saw.

If you plan to insulate the floor, then under the frame, in accordance with the manufacturer's recommendations, you need to lay a vapor barrier. But after installing the lag, a suitable thermal insulation material: mineral wool, expanded clay, ecowool, linen or synthetic mats.

Laying plywood boards

The most controversial issue is the thickness and number of layers of plywood. There is no single correct opinion. It is clear that the higher the expected load on the floor (weight of furniture, intensity of foot traffic, etc.), the greater should be the thickness of the slabs and the smaller the distance between the lags. This will avoid the deflection of the structure and its damage.

What type of floor is best - single or multi-layer? There is no definite answer to this question. Each type has its own advantages and disadvantages. But the total thickness of the plywood flooring should remain constant - at least 18 mm.

Installation of plates begins with their preparation. They should be cut into the right dimensions, make cuts for communications or enclosing structures of complex shapes. Then a preliminary arrangement is carried out. The first row is laid out from the far corner along a solid wall.

Plywood sheets are adjusted if necessary, drilling points are marked for hardware with an indent from the edge - 2–3 cm and an interval between fasteners of 15–30 cm. Between the plates, as well as between the plates and walls, an expansion joint should be maintained - 0.4–1 cm.

After one row of plywood is drilled and the sawdust removed with a vacuum cleaner, the sheets are fixed with suitable fasteners. Start screwing the hardware experienced craftsmen recommend from the center of the plate, with a gradual advance diagonally to the edges, and then along the perimeter. This approach will straighten the plywood and avoid waves. Do not forget that the hardware must be "drowned" into the plywood by at least 0.2 centimeters.

The second and subsequent rows are laid in compliance with the rule of offset seams by at least 1/3 of the length. If the plywood is mounted in two layers, then the joints of the first layer should not coincide with the seams of the second.

Floor finishing

After laying, professional craftsmen recommend "walking" on the surface grinder with an abrasive nozzle from 80 to 120 units to eliminate the slightest difference between the sheets. After that, the flooring is cleaned of dust and sawdust, and the seams are filled with sealant or elastic putty for wood.

Not suitable for seams mounting foam, as it begins to sag and crumble over time.

A plywood floor can be mounted even without vast work experience, complex equipment or building education. For clarity, we recommend that you familiarize yourself with the video from professionals.

Advice! If you need repairmen, there is a very convenient service for their selection. Just send in the form below a detailed description of the work to be done and you will receive offers with prices from construction teams and firms by mail. You can see reviews of each of them and photos with examples of work. It's FREE and there's no obligation.

03.11.2009, 19:27

08.11.2009, 08:33

The golden floor will turn out with plywood 30-40.
I'm thinking of stuffing 25 boards with a gap, and on top for leveling plywood mm 3-6. Between lags and boards, as well as between boards and plywood, I'm going to lay soft material like jute or linen for soundproofing and avoiding creaking.

08.11.2009, 12:41

08.11.2009, 13:01

2andre777
what decision was made?

Plywood or board? otherwise I can’t decide myself, csp or floorboard?

08.11.2009, 15:40

After painful thoughts and accounts (by the way, I’ll post an estimate here for the sake of inters FULL on my box (maybe someone will scold you) in a month or two ...
So (including insulation, a bottom seam with 4 mm plywood instead of an inch board):
The top layer will be if, then...
Plywood 10 mm 3 layers - 38 tyr
OSB 10 * 3 layers - 37 tyr
edged board 40 mm + plywood 10 mm - 25 tyr
Batten 40 mm grooved - 28 tyr

I chose a board, throwing away the cheap version of the forty + plywood, since it will be merciless and doubtful in terms of strength to deflection with a point load.
The DSP somehow didn’t think that the all-woven material is fragile and heavy and it’s more difficult to work with it, its current was thought under the bathroom tile on the 2nd floor after the board .... or GVL ..

08.11.2009, 18:26

That's what forums are for!

Thank you, helped to lean towards the same option, i.e. board 40mm (beam pitch 600), and csp for underfloor heating and for tiles in the bathroom ...

11.11.2009, 14:26

boards 25 on the floor??? not enough?
What is the distance between the lags?
"if the ratio of the width of the board to the height is less than 2, then the span is up to 15 heights, if more, then up to 20 heights"
I have a distance between the lags planned - half a meter. 25 mm boards just fit here. But if the topikstarter, with its 40 mm, takes a distance between the lags of 1 meter, then this will be a surprise.

11.11.2009, 18:43

But if the topikstarter, with its 40 mm, takes a distance between the lags of 1 meter, then this will be a surprise.
And I have 400 mm between the axes of the beams: D

12.11.2009, 08:50

And I have 400 mm between the axes of the beams: D
Then 40 is superfluous, 25 will be enough. Take 30 as a last resort.

12.11.2009, 09:19

I chose a board, throwing away the cheap version of the forty + plywood, since it will be merciless and doubtful in terms of strength to deflection with a point load.
Flexural strength? The board provides strength. Plywood is just for the smoothness of the floor.

The question of price is also strange for you. Normal floor board 12 thousand per cubic meter. A simple rough board for flooring on top of plywood - 4 thousand per cubic meter.

At the same time, I don’t understand why all this will creak more than the board. There are no more connections-sources of creaking. Moreover, I am going to lay boards with a gap, i.e. they will not touch and will not be able to creak. And in any case, it is desirable to lay with a soft material. When someone walks in heels, the sound will spread throughout the house. So in order for it to be muffled, it is necessary to lay horizontal joints with soundproofing. And with such a gasket, a creak is generally impossible.

And further. You floor board for 12 thousand. still tormented to lay. There, first you need to lay flat, then wedged. A year later, when the boards are dry, wedged again. This does not guarantee that after the heat is supplied, this entire household will not dry out again with the appearance of cracks and creaks.
My version in this respect is much less time-consuming.

12.11.2009, 10:17

The floorboard itself after the varnish is already a floor covering, unlike plywood. Plus aesthetics. Wedging the board when laying the floor is not such a difficult task.
Boards should be bought immediately dry and laid in the summer at maximum humidity so that they do not stand up like a hump, what kind of drying out is there

12.11.2009, 10:31

Your version looks more technical)))
and how much will m2 cost in your case, excluding soft padding and flooring? And what gasket do you suggest to use? I only remembered polyethylene foam. with a thickness of 4-5 mm, these are pennies ...

At a cost of 12 tons per cube of 40 mm floorboards, m2, it turns out to be about 500 rubles. but of course there is no soundproofing ...

12.11.2009, 11:08

The floorboard itself after the varnish is already a floor covering, unlike plywood. Plus aesthetics.
Am I against it? Who likes what. It's just my budget option. But everyone chooses for himself based on his needs.

12.11.2009, 11:15

and how much will m2 cost in your case, excluding soft padding and flooring?
Consider. We have a cube of shaved lumber costs 4 tr. If you take a board of 30, then you get 120 rubles per sq. per board. Plywood 6mm FC birch costs about 230 rubles per sheet, i.e. 100 rubles per sq.

And what pad do you suggest to use?
After assembling the log house, I have a lot of jute ribbons left. I will put him into action. Plus, I like it better than foam plastic.

What does horizontal clearance mean? between what and what?
Between the joists and the board, and then (optionally) between the board and plywood.

12.11.2009, 11:38

And for some reason you do not take into account the final floor covering in the price. This I mean that making the floor right away is no more expensive than blocking the subfloor, and laying the topcoat on top.
I am laying laminate on plywood in my apartment out of desperation, if there were options, I would lay a normal floor

12.11.2009, 11:58

What is the finish coat?
Similarly, you can varnish and plywood. The texture will remain just as good, there will be fewer seams, it will be smoother, stronger, etc.

12.11.2009, 12:25

Flexural strength? The board provides strength. Plywood is just for the smoothness of the floor.
I'm talking about strength under load, for example, a sofa leg, it will put pressure on plywood and one (!) Board under it, i.e. near standing boards do not participate in the work of distributing the load.

12.11.2009, 12:48

Don't you think that the same sofa leg will put pressure on more than two boards, even if they are fastened with a spike? The spike does not distribute the load very well at all. It is more for stitching gaps.

Press on plywood and one (!) board under it

12.11.2009, 13:08

The floor is made of painted plywood ... it happens, it would be interesting to see. How do you do it plz post pics

12.11.2009, 13:44

It seems to me that you are confusing plywood with paper. :lol:
In this regard, the two-dimensional surface of the plywood distributes the load much more efficiently than the one-dimensional tenon. Despite the fact that the thickness of the spike and plywood are comparable.
but the spike is shorter. and plywood - to the nearest board ... with what clearance is the board then?

12.11.2009, 14:27

I was talking about varnished plywood. But with painted it is even easier. Just perfect one color Smooth surface it turns out, on which even the seams can hardly be guessed with good putty.

12.11.2009, 14:42

but the spike is shorter. and plywood - to the nearest board ... with what clearance is the board then?
Gap 2-5 mm.

Do an experiment. Stretch the sheet and place a ball in its center. Now evaluate the fabric pre-fungus in relation to the attachment angles. This picture characterizes the distribution of loads when using plywood.

Now another experiment. Stretch the ribbon and place a ball in its center. Have you seen how the load is distributed now? This characterizes the load on the board.

Another explanation on the fingers. Along the fibers, the tensile strength of the board is about 100 MPa. Across - about 20 MPa. Now we cut the board and fasten it with a spike. I don’t know what the tensile strength will be, but it is unlikely to exceed several Pa (NOT MPa). For plywood in all directions, this parameter is approximately 100 MPa.

And in general, you clearly underestimate the strength of plywood. Floor beams are made of plywood so long that the length of the board is simply unattainable (the full name is glued box-section beams with plywood walls). I have already calculated for myself a run of 7.5 meters from plywood 45 cm high. When it is warm, I will glue it.

Therefore, if we compare the floorboard 30-ku with a spike and a simple board 30-ku with 6mm plywood on it, then the second option will be definitely stronger.

12.11.2009, 14:55

This is if you put 30 close. and if without a spike and a gap ....
And you count like this. You have a weaving floor board. on both sides, a spike and a groove of 5 mm each, which do not work like a board of 30. Those. In any case, 10% of the width of the board will not work for you, but play a purely technological role of redistributing the load. But plywood performs this role more efficiently (see the post above).

12.11.2009, 15:12

It seems to me that you are confusing plywood with paper. :lol:

Well, what confuses me is that the edged board is mostly raw and not quite the same thickness, it is necessary to select it, but if you buy a finished flooring (450-500 r / m2), then here I will accept each upon purchase and lay (I hope) without problems. The problem is different, after the floor there will be partition walls on the 2nd floor, so it will be impossible to knock down the boards in the future, so apparently you need to look for either a very well-dried board or choose another option.

12.11.2009, 16:18

Puttying wood floors is the last resort. Tumbles nafig, the wooden floor walks and vibrates. Changes geometry depending on humidity and temperature.

12.11.2009, 16:19

Well, what confuses me is that the edged board is mostly raw and not quite the same thickness, it is necessary to select
It depends on the office. One of us has set herself some kind of sawmill, so their board comes out even, almost like a planed one. The price is the same as others. They are simply located in the village 20 km away. from the city, so they are spinning to compete with the inner-city ones.

The problem is different, after the floor there will be partition walls on the 2nd floor, so it will be impossible to knock down the boards in the future, so apparently you need to look for either a very well-dried board or choose another option.
I will have the same. This is also the reason why I want a simple board with gaps.
Well, if you really really want a floorboard, then you first need to make partitions, and then lay the floors in order to weddle in each room separately. I understand so.

12.11.2009, 16:29

The board can be flat - the same thickness, but you still have to equalize the height difference at the beams ...

Every idea has its advantages.

Edged board + plywood or chipboard:
- better sound insulation (two damping layers, maybe three)
- versatility (laminate, tiles, etc.)
- no creaky, rubbing structures
- does not require wedging when drying out
- you can lay a film warm floor
- the price depends on your frills, either laminate on sale, or elite parquet

Batten:
- 100% natural, not counting varnishes, etc.
- no need to worry about the choice of laminate, choose the color of the varnish and that's it ...
- cheaper, cheapest option

Everything seems to be the floorboard has one serious plus - this is the price with a decent, albeit country-village look

13.11.2009, 06:39

Well, if you really really want a floorboard, then you first need to make partitions, and then lay the floors in order to weddle in each room separately. I understand so.
Oh, well, such a torment in the bath: D there will be too much waste of the floorboard, if you want - set it and forget it: D
I think it might be another option to calculate, spread 4 mm plywood and shackle a 30 mm screed on top of the wire mesh (as a reduction in price), pull it crosswise over the carnations and pour it .. :shock:

20.11.2009, 20:19

I did this for myself:
Beam 10x10 beam, distance between beams 60 cm. I bought an unedged board 30, sanded it and laid it on the floor on self-tapping screws.
Then he put 3 mm isolon. and put 20mm chipboard on top. (pre-priming it). Chipboard also planted on self-tapping screws.
I threw linoleum on top, as a result, nothing creaks or bends anywhere.
Here is a photo

20.11.2009, 21:49

Then he put 3 mm isolon. ..
What is his purpose in this pie?

21.11.2009, 12:59

Then he put 3 mm isolon. ..
What is his purpose in this pie?

Warming and so as not to "creak" (when the chipboard is deflected so that it does not come into contact with the board). This is the first floor, I will do the second floor in the same way, only instead of chipboard I will put plywood 15-20 mm. Let it be more expensive but more environmentally friendly.
By the way, a friend put 5 mm isolon. and from above OSB board 9 mm. when he walks, dips are noticeable due to the thick isolon.

21.11.2009, 13:17

How can you not be afraid to put chipboard at home, and even not laminated?! Maybe all the same look at the DSP (if available on the market), the same chipboard only without phenol and other cement-based chemicals. With plywood, you also need to be careful, most manufacturers save on our health.

Leveling floors before rough and fine finishing directly depends on the height and area of ​​​​the room. But this process is also influenced by several other factors. What will be the floor covering, in what range of temperatures and humidity will the floor be, how much is planned to be spent on Finishing work, what are the attitudes of tenants in aggressive adhesives and solutions, etc. All of the above questions make the choice of floor leveling material not so simple. To date, homegrown builders and recognized masters of repair have not tried anything! Here we will talk about plywood, which is an excellent material for flooring in residential and non-residential premises. Plywood sheets of different thicknesses and formats are used both for rough finishing before laying laminate, linoleum or parquet, and for fine finish floors in cottages, in the country and at home.

How to use plywood

Initially, it may seem that plywood sheets are fragile and cheap. But practice shows that this material is many times superior to MDF, chipboard, OSB, fiberboard and other recycled materials. And there is no need to ask a difficult question,. The main advantage of plywood lies in the specifics of its production. There is no gluing of the residual mass of wood and a liquid binding substance here. Each plywood sheet consists of several layers of working wood. And due to the fact that these layers have multidirectional fibers, the floor is durable and reliable. You can read about what it is in the article.

You can find out how much 1 sheet of moisture-resistant plywood costs from this

The purpose of plywood flooring is to achieve three main tasks.

1. "Smoothing" of irregularities and preparation for a final coating.
2. Ensuring the required level of thermal insulation.
3. Protection of the parquet board from moisture.

Of course, there is also plywood for finishing the floor. But we will not consider this option because of its specificity and low prevalence. They lay plywood either directly on the floor, or raise it above it with the help of logs - special lighthouse bars.

What are specifications moisture resistant plywood can be found in this

On the video - the thickness of plywood on the floor:

Methods for laying sheets on the floor

Put on logs

If the differences in height on the floor are quite significant (from 5-10), then plywood can be laid and fastened to special logs. They not only allow you to achieve a perfectly flat floor, but also provide air cushion for thermal insulation and waterproofing, and then it is easier to select or other finishing material.

Lags are used almost everywhere. The only obstacle on this path is the low height of the room, since laying plywood on logs “eats” up to 10 cm of room height.

Manufacturers and prices

When choosing a finish coating, it is useful to know.

The prices for their products are about the same. Therefore, experts recommend, first of all, to determine the type of plywood sheets that will be used for flooring.

Leveling the floor with a plywood "substrate" is a common method of dealing with unevenness, cold and operational features of the room. Depending on the tasks used different types plywood and their thickness. If you are just looking at the material, it is useful to know and.

You can see a photo of OSB plywood in this particular

In each specific case, a professional needs to do an assessment of the needs in one type or another.

What are the pros/cons of these materials?

Currently, you can choose any material in hardware stores, including for floors. We are so carried away by new technologies that sometimes we forget about the environment, and this is an important factor: after all, we will live in this house. And here the price problem comes to the fore. And if financial question it’s not a problem for you, it’s better to choose from the proposed two options: first of all, of course, the floorboard, and then you can lay plywood on it, but laminate is better. The OSB option can be discarded immediately: OSB does not stand the test of time and begins to crumble over time. So, we choose the floorboard.

In terms of strength and durability, it is unlikely that any of the materials proposed above will be able to compete with the floorboard. Therefore, there can’t even be options here, only a floorboard. And later you can put on it whatever your heart desires, from carpet and linoleum, to the same OSB or plywood, although you can just paint the floorboard or even grind it, that's how much))). Yes, and mounting it on the logs is quite simple. OSB and plywood simply do not withstand the mechanical load that the floors are constantly experiencing and within a short period of time they begin to collapse, and the OSB simply crumbles, and the plywood begins to peel.

First of all, you need to decide on the so-called environmental friendliness of these materials. This, in my opinion, is one of the most important issues in the approach to the choice of these materials. The fact is that plywood and OSB boards contain formaldehyde resins, with the help of which all the components of these materials are fastened and pressed. The floorboard can also be glued together from pieces, but in the latter version, the resin content there is many times less. It is also necessary to take into account the coefficient of linear expansion of these materials at different humidity and temperature. Well, and accordingly moisture resistance.

For flooring, such material as plywood is increasingly used. However, if we are talking O wood flooring, then putting plywood on a wooden floor is not so easy, there are certain nuances that must be considered.

First of all, you need to understand what plywood is. This is a material consisting of 3 layers of wood, but it often happens that there are more such layers. There are several types of such material, so if the question arises of which plywood to lay on the floor, it is recommended to opt for a waterproof version, which is impregnated with a special adhesive solution.

Plywood is great for subflooring as it is durable and won't warp.

Covering a wooden floor with such material is very good decision since it has whole line benefits.

First of all, it should be noted that it is plywood that is the most practical subfloor for a living space. When such a floor is in use, it cannot be deformed, since there is no doubt about the strength and reliability of such a coating. This material can be used not only as rough coating, but also as the main one.

But you should know that before laying plywood on a wooden floor, there must be a certain gap between its sheets, which does not affect the appearance of the floor in the best way. To avoid this, the plywood laid on the floor must be sanded (for this it is recommended to use fine-grained sandpaper), then everything is varnished and it turns out to be very attractive and prestigious. appearance. For all this, you need to use the following tools:

Hammer.Nails.Secrets.Screwdriver.Level.Hacksaw.

Plywood comes in 1-4 grades.

Using moisture-resistant plywood will allow you not to be afraid of the consequences of a flood, which neighbors from above can always organize. If we talk about the advantages of such a material, then it should be noted excellent thermal insulation qualities, which allow you to save heat 20% more than other materials.

Laying plywood on a wooden floor is especially recommended in cases where it has completely become unusable (either dried out or loosened).

Using such material, you can put everything in order very quickly and inexpensively, and it will be very reliable. But if there are significant temperature differences in the room, then it is best to refuse to use plywood, the same applies to apartments where there is high humidity. That is, it is not necessary to lay plywood in the bathroom or in the room where there is no heating.

Scheme of laying plywood floor parquet.

When the question arises of how to lay plywood on the floor, the most difficult thing is laying it on the logs. They must be installed so that the upper ends are in the same horizontal plane. Plywood should be attached to the logs so that they have a docking of sheets.

If necessary, a heat and sound insulating layer can be installed between the lags, and communication networks can be installed. It is recommended to use plywood sheets that are approximately 1.5 cm thick.

If moisture-resistant plywood is used, the thickness of which is 1.2 cm, then you need to drill 6-8 holes with a diameter of 1 sq. mm.

Then, in such holes, you need to insert plastic bushings that have internal thread. These holes are needed in order to screw the bolts into them (they are also plastic). Such bolts are used as racks.

Now the sheets are installed on the wooden floor, the surface of the plywood should be horizontal.

Plywood is laid on logs and nailed or self-tapping screws every 15-20 cm.

Before you start laying plywood sheets, you need to check for deflections in the wooden base along the logs. If there are such deflections, then the flooring will need to be removed, and the floor needs to be repaired. If this is not the case, then plywood can be laid directly on the base.

Before starting work, it is necessary to check the level of humidity of the surface of the base. This is done quite simply: a piece spreads polyethylene film, the size of which is 1 by 1 m for a period of 72 hours, the film should be pressed to the surface as tightly as possible. If after the specified time inner side polyethylene is not covered with condensate, then work can begin.

Plywood is laid with an offset so that the seams do not converge in one place.

Plywood sheets should be laid with a small offset, in one place more than 3 seams should not converge. Sheets in the process of laying should not be tangled, they should be numbered. As for the gaps between the sheets, there should not be more than 3 mm, and between the plywood sheet and the wall there should be a distance not exceeding 1.5 cm.

Squares are carefully cut out of plywood sheets, the size of which is 60 by 60 cm. In this way, a large number of damper joints are obtained, which makes it possible to very effectively identify existing plywood delaminations, since they can simply be unnoticed on solid sheets.

It is very important to clean the plywood with a construction vacuum cleaner before installation, dust and dirt are unacceptable.

Plywood can be laid different ways but it is best to use glue. However, you can safely do without it. The sheets must be laid taking into account the numbering, diagonally they must be fixed with self-tapping screws, the distance between which should be from 15 to 20 cm.

You can make an indent from the edge of the sheets, but it should not exceed 2 cm. It must be remembered that the self-tapping caps must be completely recessed into the plywood sheets, the holes in the fasteners must be countersunk. After the plywood sheets are laid, they must be carefully sanded.

Thus, it becomes clear that this type of flooring really has many advantages. And, first of all, it should be noted that the cost of such work is relatively cheap, and the workflow itself is not difficult. So we lay plywood on a wooden floor on our own, without fear for the quality of the final result.

All photos from the article

Plywood is strong enough to withstand the stress of furniture, so plywood sheets are often used to level any type of floor. In addition, this allows it to be insulated, which is especially important for the first floor with an unheated basement. The work of laying plywood on a wooden floor cannot be called too difficult; even a beginner in the construction business can cope with this task.

Benefits of plywood flooring

Using plywood for flooring has a number of advantages:

easy to level the wooden floor. Moreover, it is possible to eliminate both local defects, such as slight irregularities, and more serious shortcomings, for example, the curvature of the floor;

warm it up. If the flooring is carried out on logs, then insulation (bulk or rolled) can be laid between them, heat loss through the floor will decrease significantly;

laying can be done with your own hands, even assistants are not needed. All that needs to be done is to mark up the room and fix the sheets on the floor in accordance with the layout plan, attaching them to the base with screws.

Materials such as fibreboard cannot be considered as replacements due to bad work bending and lower durability in general. If plywood sheets can bend without problems, relying on ribbed floor, then fiberboard simply cannot withstand such a load.

Pay attention! Fiberboard should not be used even to eliminate small defects on the surface of the floor. Any irregularities will eventually be reflected on their surface.

Another advantage of plywood sheets can be considered their low cost. Especially when you compare their cost with the price of floorboards in a room of the same size. So the relatively low price of plywood for the floor can also be considered a significant factor when choosing a material for the floor.

Which plywood to choose

When choosing, you will have to take into account factors such as:

plywood dimensions, attention should be paid to the thickness, the deflection under load depends on this, this is especially important when laying on logs;

Pay attention! It is also worth considering the width and length, these parameters are important simply based on the convenience of transportation. If the work is carried out in a city apartment, then it will be inconvenient to transport sheets a couple of meters high, to put it mildly.

plywood type. For residential premises, the FK type (based on urea adhesives) is suitable.

On sale, you can also find options using adhesives on phenolic compounds, but they are more dangerous to human health, although they are highly resistant to moisture. Bakelite and even more so laminated plywood sheets for the floor are definitely not suitable; as for surface treatment, if linoleum, laminate or any other type of floor covering is laid on top of it, then you can take the simplest - unpolished type; depending on the presence of defects in the outer layers of veneer plywood can be divided into grades. For flooring, grades 3 and 4 can be recommended, since the floor covering will still be located on top of it, the number of defects does not matter at all.

As for the thickness of plywood to lay on a wooden floor, it can be recommended not to use sheets less than 18-20 mm thick for single-layer flooring. Also, to increase the rigidity and strength of the plywood layer, you can lay it in 2 layers.

Methods for laying plywood sheets on a wooden floor

In this matter, a lot depends on the condition of the wooden floor, as well as on whether it is planned to be insulated. There are several ways to get the job done.

Flooring directly on boards

This method is used when the old plank floor is still strong enough, but the gaps between the floorboards, and the unsightly appearance does not allow leaving it as it is. It is too expensive to completely re-lay it, and it is impossible to lay a laminate or linoleum directly on such a base. In such situations, the question arises, how to lay plywood on an old wooden floor?

If the flooring is also carried out to level the base, then a two-layer coating would be ideal, sheets with a thickness of 9-10 mm can be used for each layer. In this case, the seams of the upper layer should fall in the middle of the underlying sheet, this will smooth out the unevenness of the base caused by different thickness floorboards.

The laying of sheets is carried out in the following sequence:

First you need to check the boards for strength and deflection. It may well turn out that the lags are rotten, in which case they will have to be replaced.

You should not try to save money at this stage, the stronger the wooden base, the longer the floor will last. Before laying plywood, the floor is thoroughly cleaned; further instructions involve laying plywood sheets on the floor. It is forbidden to lay them close to each other, the thickness of the seam should be about 3-5 mm, and the distance between the wall and the sheet is 15-20 mm (then it will be closed with a plinth);

Pay attention! Humidity in the room plays a special role. To check, you can lay polyethylene on the floor and after a couple of days see if there is any condensation on it. If not, then the plywood is guaranteed not to become damp.

when laying, each next row must be shifted by about 1/3 of the width from the previous one (approximately the same as ligation of seams is performed when brickwork). At one point, more than 3 seams should not converge;

plywood sheets can be attached to the base with glue, self-tapping screws, or with the help of both. As practice shows, self-tapping screws are quite enough, the sheet must be fixed around the perimeter and diagonally with an equal pitch between the screws. In order for the heads not to protrude above the surface of the sheet, countersinking of all holes for self-tapping screws is mandatory;

after that, the question of how to lay plywood on a wooden floor can be considered closed, it remains only to check if the sheets bend due to the unevenness of the plank floor, and you can proceed to laying linoleum, laminate or other flooring.

Leveling the curvature of the base

Laying plywood on logs can be used if it is necessary to insulate the floor, as well as in cases where the old floor has a significant curvature.

for log use ordinary square bars, if the floor has a slope, then using bars different section For different rows curvature can be eliminated. Instead, it is allowed to put trimmings of wooden boards under a row of bars;

in the question of how to properly lay plywood on a wooden floor on logs, it is important to ensure the rigidity of the coating. To do this, it is necessary to take a small step between the lags (about 40-50 cm), and for greater rigidity, lay the bars also in the transverse direction. Due to this, the sheets will be supported along the entire perimeter and the deflections will be less than when supported only along the edges;

with such fastening of plywood, the clarity of the markup is especially important. The edge of the sheet should fall clearly in the middle of the bar, it is fastened to the logs with the same self-tapping screws, you can additionally apply a layer of glue to the logs.

Instead of a log, it is possible to install point supports under plywood flooring. The whole difference lies in the fact that instead of a log, point supports of the desired height are installed on the old base. They should create a dense grid on the old wooden floor, the step between the supports is 35-50 cm.

Please note! With this method of flooring, the edges of the sheets should in no case sag.

As for which plywood to lay on the wooden floor on the logs, the same sheets are used as for flooring directly on the floor. The degree of surface treatment of the sheet is selected depending on whether the flooring will be laid on top of the plywood.

In conclusion

Laying plywood sheets on a wooden floor is the easiest way to not only eliminate defects wooden base, but also a good increase in the heat and sound insulation characteristics of the floor. This work is not difficult, and the proposed recommendations will allow you to do it yourself, without outside help.

The video in this article describes a number of nuances of laying plywood on a wooden floor.

You can always ask questions related to the technology of laying plywood sheets on the floor in the comments to the article.

Both in new buildings and in houses commissioned several decades ago, residents are faced with the task of leveling the floor to change the floor covering, whether it be linoleum, parquet or parquet board, laminate or something else. But the modern market offers such a wide range that it is sometimes difficult to give preference to one or another building material. The purpose of this article is to dispel all doubts and help make a balanced, reasonable choice before starting repairs in own house or apartment. Of the variety of materials suitable for these purposes, the choice comes down to four of them: When choosing a flooring for leveling the floor, you need to take into account the characteristics of each. Fiberboard is a material made from compressed wood fibers pre-treated with steam. Synthetic resins or paraffin are used as a binder. The production technology does not allow making thick fiberboard, and the raw materials used (most often wood processing waste) achieve satisfactory strength.

Of the entire list, plates of this kind are the most fragile. Moreover, if the draft surface has significant, and even more so local solid protrusions, for example, an influx of concrete or a piece of reinforcement sticking out of the screed, this species material can be damaged even at the marking stage. DSP - slabs of chips of small and medium fractions bound by cement. In addition, a number of chemical additives are added to the composition to reduce negative impact chips for cement. At the same time, DSPs have a higher density, and hence more weight with the same area.

They are quite fragile to fracture, although they are somewhat stronger than fiberboard, while being more resistant to moisture, heat, and much less susceptible to mold fungus. with incomplete quality control, the production technology may be violated, then the release of phenols may exceed the permissible limits. Plywood is the most environmentally friendly from this list. Technically, it consists of several layers of birch (rarely coniferous) veneer glued together. Has a relatively low specific gravity, and surpasses all other materials from this list in strength. For a number of reasons, it is plywood that is much more convenient to use for repairs: Time saving. In addition to the usual formats of 1.5x1.5 meters, sizes of 2.5x1. meters - in one time you can cover a large area.Effort saving.

Even a large sheet can be carried by one person. Resilience. Adjacent veneer layers are oriented perpendicularly, which ensures strength in all directions. This quality will provide higher wear resistance both during installation and during the operation of the floor. Elasticity. If there are some local irregularities of the subfloor in this place, the sheet will be washed without much loss, and this area will remain flush with the rest. Due to the elasticity, the material will not crumble or crack either during installation or during operation. Environmental friendliness. In most cases, natural resins or natural-based adhesives are used, which increases environmental and consumer safety. Porosity.

Due to its natural origin, this provides ventilation, which will prevent decay of the lower surface of the finished floor. brief characteristics it is quite enough to make an unambiguous conclusion: in a number of properties, a plywood floor is better than a floor made of OSB-plate, DSP or fiberboard. There is no need to choose the highest grades for rough work. Moreover, the third grade is also suitable for repairs (according to current standards, there is also a fourth grade, but it is almost never found on the market) - for the set goals given choice optimal. Small irregularities, roughness needs to be cleaned sandpaper or cut with a knife. Of course, if there are obvious geometric irregularities, “rolled up with a screw” or, as the builders say, “behaved”, as well as sheets with obviously not right angles, such options are not applicable. When buying, it is also important to check that whether there was damage during storage - for the absence of chips, kinks, damp areas, traces of the vital activity of rodents, insects or mold fungus. Many repairmen literally determine the quality of the sheet by smell - undamaged material has a noble woody smell with barely noticeable notes of glue. You can often hear from sellers classification designation according to international standard ISO (and sometimes, according to their own quality system, up to “TBS class F-1 brand”), so you need to clarify the grade according to Russian GOST, or, looking at the packaging, the product grade must be noted. Perhaps some of the material will go away as a waste, therefore, it is better to purchase with a small margin, about 5-10%. As for the thickness, builders are guided by a simple rule - the thicker the better. Indeed, a thicker substrate can hide larger defects.

In this case, you should not overdo it, the minimum is 8 mm, the recommended one is from 14 to 22 mm. In any case, the underlay should not be thinner than the final floor covering. It is preferable to use sheets large sizes, but if their transportation or laying is difficult, smaller dimensions can also be used. Some stores may offer cutting into more convenient ones for transportation. In order not to reduce the quality in the future, it is enough to carry out a simple preliminary processing. This stage consists of several simple operations. Drying. Before starting repairs, plywood must be brought into a dry, warm room and kept for at least a week (ideally, two to three weeks). This will save her from excess moisture, which she could absorb during transportation and storage.

Such a long drying time is due to its structure - moisture that has penetrated into the deeper layers evaporates much more slowly than from the surface layers. Biosecurity. To avoid the reproduction of destructive microflora, you can soak at least the outer layers with antiseptic solutions. water will seep from above or condensation will accumulate from the concrete. Ventilation. After antiseptic treatment, withstand at least a day. Of course, while maintaining minimal gaps. You can add moisture resistance by applying one or two layers of acrylic-based varnish.

At least two days before the start of work, plywood must be brought into the room where the repair will be carried out. The workpieces must be laid horizontally, allowed to “rest”, relieve excess stress in the structure caused by storage in a vertical position.

The floor must be prepared: remove the old plinth, remove all debris, dust, knock down the irregularities of the concrete and cut off the protruding parts of the reinforcement, soak with an antiseptic solution.

If flooring is performed without a log, the concrete surface must be leveled, if possible, with a cement-sand mortar, then apply a primer and allow to dry. Cement-sand mortar seizes for several days, allocating all this time in environment excess moisture, so it is better to start preparation in advance.

If the height differences during the level check turned out to be large, it is necessary to perform a screed or lay logs to compensate for irregularities.

If laying is carried out on top of old boards, inspect their condition. Rotten or crumbling areas must be replaced, creaking or staggering - fixing. On a wooden base, you also need to apply a primer, an antiseptic and dry it.

At the next stage, you need to lay out the sheets as they will subsequently be fixed. Compensation gaps should be provided: between the elements 3-4 mm, from the wall 8-10 mm, this will avoid swelling if the temperature or humidity conditions change.

In the process of cutting, it is necessary to coat the ends of the sheets with glue in order to avoid their cracking in the future.

Mark the workpieces, while indicating the orientation of the workpieces in one direction, either with the inscription itself or with an arrow.

For example, indicate the row with a letter, the number with a number, that is, A1 is the first element in the first row. This will help avoid confusion in the future. For convenience, you can sketch a laying scheme on paper.

It is worth avoiding cases when the corners of four neighboring fragments converge at one point. In other words, lay out the workpieces "in a row", as in brickwork.

For installation, you will need the following tool:

Electric jigsaw. It is unlikely that it will be possible to cover the floor with solid sheets, and perhaps when the angle formed by the floor and wall is not perfectly even, it may be necessary curly cutting. In addition, it will be necessary to bypass the riser pipes at their exit points.

For these purposes, a circular saw is much less suitable, as it allows you to make only a straight cut. Building level. A level at least 2 meters long is preferred, as a shorter tool will not allow you to notice unevenness at long distances. Tape measure and pencil. After preliminary unfolding, carry out the necessary marking and marking before cutting.

Construction knife. Screwdriver with a bit corresponding to the fasteners used. Vacuum cleaner or broom. Means personal protection: durable gloves, glasses, knee pads, if necessary - headphones (ear plugs).

From additional materials:

Self-tapping screws (self-tapping screws) - if laying on logs or an old wooden floor.

Fasteners are selected according to a simple formula - the thickness of the fixed element is multiplied by three. For example, if the sheet is 20 mm, then the length of the self-tapping screw is at least 60 mm. In this case, the screw should not be longer than the total thickness of the flooring and the wooden base. Dowels corresponding to self-tapping screws - if mounted on concrete or screed. Wood glue (most often used ordinary PVA) or “liquid nails”. Sealant (polyizol).

Depending on the condition of the repaired premises, different methods of installation of the rough base are used:

over a concrete floor (or screed); over an old wooden floor; on logs.

Based on this, one or another mounting technology is used.

The technology of laying plywood on old floor boards is quite simple. In your own house or apartment, it is quite feasible to do these works with your own hands.

After all preparatory activities you need to spread and cut the substrate. It is important to avoid laying "overlap", preferring "butt" so as not to add bumps. Fasten the joints of the seal with a wide adhesive tape, cut off the excess.

Then proceed to the layout according to a pre-drawn plan, observing the markings. Start from the corner, gradually expanding the "spot" in both directions.

The elements are screwed with self-tapping screws, retreating from the edge of at least 2 cm, and with a step between the attachment points of not more than 20 cm, sinking the hat.

For the log, a beam of coniferous wood is selected, with a section of at least 50x50 mm. Preference should be given to dried timber without visible violations of geometry (not twisted “into a screw” and without bends along the longitudinal axis), without chips and other mechanical damage.

In order to isolate wooden elements from dampness from below, before laying them, it is advisable to lay a pre-insulation (polyizol), fastening the seams with adhesive tape.

It will be correct to start laying logs from the highest point selected using the level. It is important to keep the beam laying step uniform, 50 - 60 cm, no more.

The laying rules require that you observe the maximum possible horizontality, if necessary, placing pieces of the same timber or any rigid inserts that are resistant to moisture and fungus from below, it is also permissible to mount them on glue or, if dimensions allow, screw logs to them with self-tapping screws.

Mounting on concrete is sufficient to perform glue or "liquid nails". To improve heat and sound insulation, foam or mineral wool can be laid between the lags.

It is important to choose the right plywood thickness, the golden rule: the base should not be thinner than the top, “front” coating. allowed values lag layout step to avoid sagging and damage to the finished floor. If used thin sheets in two layers, it is worth avoiding the coincidence of the seams in the upper and lower layers.

In order for the self-tapping screws to be securely recessed, you can pre-drill the attachment points with a drill, and then make a shallow 3-5 mm drilling of a slightly larger diameter.

In this case, the flooring is made according to the old wooden floor in compliance with horizontality, threaded stud segments are used, closed with PVC corrugated tube.

The floor is covered with plywood evenly, the seams between the sheets are treated with sealant and putty.

Mounting along the joists is made with solid sheets with a minimum of cuts, compensation gaps between the sheets are taken into account. Mineral wool is laid between the lags as a heater and sound insulator.

Preparations are underway for flooring along the logs, the concrete floor has been leveled, and a polyethylene film has been laid for waterproofing.

For speakers at the edges metal elements cuts are made with minimal loss of load-bearing capacity. Self-tapping fastening. Mineral wool in the space between the lags.

For information on how to level the floor with plywood, see the following video.