Plumbing

Do-it-yourself mansard roof. We build a mansard roof with our own hands

plywood like construction material currently enjoys special demand. It is suitable not only for household use, but also as a base necessary for the construction of furniture, ships, and air transport.

This type of material is used as a source for laminate, linoleum, carpet, parquet. The plywood floor in the apartment looks very good. It is important to know all the advantages of this material:

plywood bends quite easily, cracks do not appear on it;
equal strength on the entire base;
convenience during transportation;
significant dimensions of the layers.

This material is characterized by such indicators as good water resistance, high grinding limits, strong surface, no smell, ease of installation, light weight, special strength.

Material Features

Plywood is a special material with a layered texture. It is produced by pressing and gluing wood layers of a given thickness. High layers of this material will tell about its strength and special reliability. The number of layers in plywood must be odd.

The following classifications of this material are distinguished:

varietal affiliation, consisting of external indicators of the base;
the degree of surface cleaning (choose polished and unpolished bases);
moisture resistance indicator, depending on the adhesive composition;
belonging to an ecological class.

Plywood grades differ in the degree of processing and in the raw materials used.

There are 4 groups of plywood, divided in accordance with the requirements of state standards. They are characterized by a different number of flaws and the quality of the veneer. It:

1 grade has the most high rates quality: does not contain flaws in the external plan, slight warping of the veneer within 20 cm is possible;
Grade 2 has wood inserts, small traces of glue, dents;
Grade 3 characterizes the presence of knots, cracked foci;
Grade 4 is distinguished by poor quality material; a large number of lesions can be found on it.

As an impeccable option for flooring, there will be grade 2 matter. The named material is made from species of deciduous and coniferous trees: birch, pine, spruce, fir, cedar. Pine needles contain a large number of useful components, phytoncides, which have a beneficial effect on human health. They destroy pathogens.

However, the adhesive composition with formaldehyde-based resins nullifies all beneficial features plywood. For this reason, these varieties are used when installing the roof. Birch is suitable as a floor base. It has a fairly strong coating, completely harmless to the human body and retains heat well in the room.

Despite the wide variety of plywood, flooring material can be found infrequently. So, as such a base, grade 2 birch plywood would be an acceptable option, a convenient thickness would be 12-16 mm. It is distinguished by a democratic price and a smooth surface; it does not contain formaldehyde in the composition.

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Set of tools

In order for the flooring to please the eye with its impeccability, it is important to use the following devices:

roulette;
level;
a hammer;
drill;
screwdriver;
electric jigsaw.

How to make a floor from the material in question? The plywood base should be perfectly flat, original and should not make creaking sounds. You can give preference to any installation method. Here one should take into account the taste and material capabilities of each person.

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Concrete floor covering

You can also make a plywood floor in an apartment on a concrete floor. Such work can be done without much difficulty if the coating itself has an even base. The main stages of coverage will be:

Initial installation of a waterproofing layer based on polyethylene film on concrete. Preliminarily, the base for concrete must be leveled, thoroughly dried.
After that, plywood in the form of whole pieces is placed on the floor. Installation work should start at the threshold. This place was not chosen by chance, because it is subject to increased wear and increased exploitation.
Plywood layers are laid apart. The allowable distance between the sheets of material will be 2-3 mm, the distance from the wall is equal to 10-15 mm.
In order for the plywood to be securely fixed to the floor, plastic dowels or screws are taken. They are screwed in at the central points of the plywood and along the perimeter of the base.
An excessively large piece of this material is subjected to easy sawing. Pieces are fixed in place in the same way.
After all the work done, you can do the flooring.

Tip: fastener caps should not stick out of the base of the material, but be on the same plane with it.

The method under consideration can be used as a floor covering made of natural rocks that do not have large distortions. The sheet of the tile in question should be strengthened with nails.

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Laying on the logs

To build a plywood floor and give it maximum comfort, you should use a coating on the logs.

This structural element is represented by bars with a raw base having a section of 50x100 mm. You should take care of their acquisition in advance, because this material must adapt to the surrounding climatic conditions.

Logs are placed at intervals of 40 cm. To do this, you need to use the level. Such elements are placed throughout the area of \u200b\u200bthe room. You should also make a crate, the allowable distance between the crossbars is 50 cm.

Equal pieces of parchment are placed on the logs, which helps prevent condensation. This base has the appearance of a rolled web with a soft coating treated with butyne. In order for the base to acquire a special strength, the plywood floor must be laid in 2 layers, which are glued with PVA glue.

Such a device looks like:

layer for waterproofing;
wooden logs and crossbars;
waterproofing layer on the logs;
2 sample layers;
custom floor covering.

Fulfilling repair work it is important to know the following facts:

the edges of matter must be located on the surface of the log;
do not concentrate 4 corners at the same time at 1 point;
plywood sheets suggest leaving a gap.

Reading time ≈ 3 minutes

Leveling the floor for subsequent coating requires accuracy and obtaining the same level of the entire surface. Filling a new screed in a room is not always convenient and quite expensive. An alternative option is a plywood floor, which will be installed on the bars attached to the old screed. The thickness and width of the lag should be about 5 cm, and the length should be at least 2 m.

lag mount

In order for the do-it-yourself plywood floor on the logs to be really even, it is necessary to carry out the installation of the first beam, which is set according to the level. Work should be carried out after finishing the finishing work of the walls and ceiling.

The installation of the log is carried out not on the screed, but on the enclosed scraps of the board or timber. Such a system allows you to level even a very uneven surface with sharp drops or the presence of recesses or protrusions.

Subsequent lags are aligned relative to the previous element. This will maintain the desired level throughout the room. Roofing material should be used together with the boards to be laid. Wooden support elements can change shape with increasing humidity or temperature changes, so additional layers will help maintain the resulting surface level and protect it from curvature.

In order to correctly level the floor with plywood, it is necessary to place the logs at a distance of about 50 cm. The distance from the walls should be small and be about 3 cm.

Therefore, it is necessary to use dowels, at least 3-4 cm more than the sum of these indicators. And for the installation of plywood sheets, it is worth purchasing self-tapping screws 2-3 cm more than the thickness of the top coating being purchased.

plywood laying

Plywood is laid on the floor only after it has been prepared. With an electric jigsaw, sections for pipes, corner protrusions of the walls are cut. The thickness of the purchased sheets should be at least 3 cm, since the resulting coating should not sag under the weight of a person and furniture installed in the room.

Plywood should be positioned in such a way that the joints of the sheets fall approximately in the middle of the lag. This will allow the work to be carried out correctly and ensure the reliability of the entire structure.

A ruberoid is placed between the lags and plywood sheets. This will avoid the "movement" of the coating and its deformation during subsequent operation.

The location of plywood relative to the log should be transverse. Each sheet is attached not only along the edges, but also along the entire length of the support. It is advisable to avoid fixing in areas where people will walk.

Precaution will help to avoid damage to the floor and guarantee its long-term safety. detailed photos on the installation of the structure will allow you to see the process of assembling the plywood floor and the correct fixation of the sheets.

To understand how to make a plywood floor not only smooth, but also durable, will allow clarifying the layout of the sheets. The most correct is the displacement of pieces: it is not necessary to carry out installation with a single connection line for all adjacent pairs of plywood. This can lead to structural distortion. A video describing the entire process of creating a high-quality and durable plywood floor will help you get acquainted with the intricacies of the work. And after executing correct installation you can start finishing the leveled surface with any floor covering.

DIY plywood floor installation video

Plywood is one of the most versatile materials invented by mankind. Plywood is also widely used in construction: in terms of ease of working with it, strength, low cost and environmental friendliness, plywood is perhaps unmatched. Plywood is especially widely used in laying and repairing floors. But the high functionality of plywood also determines the variety of methods of working with it, so laying plywood on the floor with your own hands requires explanation for different cases of practice.

Chipboard or plywood?

Plywood is not the cheapest material for flooring and wall cladding. Chipboard is even cheaper. But let's leave alone for now phenol-formaldehyde resins - volatile carcinogens, on the basis of which chipboard is made.

Let's do the following experiment: put two pipe cuts on the floor and lay a sheet of plywood 12 mm thick on them. Let's get on it, let's go. What happened? Nothing. Bent over and straightened up. What about chipboard? Most likely, it cracked at a greater thickness. And it will definitely crack if you jump on it.

You can do two more experiments: hold plywood and chipboard trimmings in water and see how soon they swell and become limp. It is not necessary to knock on the edge with a hammer: everyone knows that chipboard is fragile. Therefore, the question: “chipboard or plywood?” definitely decided in favor of plywood.

What is plywood

There are many varieties of plywood. In construction, plywood of the following grades is most often used:

FC - moisture resistant plywood on urea resin, non-volatile and non-toxic. It has strength and elasticity comparable to BS aviation plywood.
NSh - unpolished on casein glue. The cheapest, about 170 rubles / sq.m with a thickness of 12 mm. Before gluing parquet or other hard flooring onto it, it requires sanding.
Ш1 - the main material going to the subfloor. Sanded on one side. The glue base is also casein.
Ш2 - polished on both sides, on casein. For lightly loaded parts in dry rooms and with comfortable temperature can be used as a substitute for FC.

What is contraindicated for plywood

Nothing is perfect, and plywood is made from a hygroscopic material - wood. Therefore, plywood cannot be used in damp rooms: long-term air humidity should not exceed 68%; short-term within 12 hours - 78%. When laying raw plywood, air humidity up to 60% is permissible.

The specified values are valid in a comfortable temperature range of 18-27 degrees Celsius. Outside these limits, the sensitivity of plywood, except for FC, to humidity increases: at 16 and 35 degrees and humidity of 85%, plywood begins to delaminate after two months. Therefore, ordinary plywood for floors and walls should not be used in the kitchen, balcony, closet, hallway and bathroom.

How to improve plywood

Moisture resistance of plywood can be increased by impregnation with putty based on polyvinyl acetate (PVA); it looks like very liquid PVA glue and is cheap. Impregnate first on one side until spots appear on the opposite side, then on the other twice. Dry in a horizontal position. It will take a long time to dry - at least 3 days at room temperature. After drying, the sheets are treated with any antiseptic fungicide for wood.

The strength of the surface layer can be increased with acrylic varnish. It is applied in two layers; the second - after the complete drying of the first. If plywood for decorative purposes needs to be stained, paint before varnishing.

Acclimatization of plywood

Before describing how to lay plywood on the floor, it should be said about its acclimatization in the room. Plywood, like any wood-based material, requires acclimatization at the place of use. The term of acclimatization depends on the difference in temperature and humidity: if the conditions in the warehouse or in the store are the same as in the apartment, a day is enough; with a temperature difference of 2 to 8 degrees - three days; with more - a week. During acclimatization, the plywood is kept stacked in a horizontal position.

Subfloor Moisture Check

Before laying plywood on the floor, the base surface, and not only concrete, you need to check for moisture evaporation. To do this, 1 sq.m of the base surface is covered with a single square piece of polyethylene film, pressing it along the edges with slats with weights and raising the center a little. The further depends on the time of appearance of condensate under the film:

The bubble fogged up from the inside during the day - the room is unsuitable for covering the floor with plywood.
Small drops appeared within 3 days - the base concrete floor must be covered with glassine or plastic film, put a construction mounting grid on it and make a screed. Wooden floor - disassemble; with such evaporation of moisture, the boards from the underside and the old logs are probably touched by rot. An option for 7-10 years is to lay plywood with an improved home method (see above) moisture resistance.
Condensation did not fall out on the 5th day: you can lay plywood in any way.

plywood base

Leveling the floor with plywood is a widespread building technique. It is used both for laying new floors and for express repairs to existing ones. For various combinations base floors and top decorative coating different plywood laying technologies are used.

Concrete

Laying plywood on a concrete floor is possible both directly on the screed and on logs. The first method is used if the base floor is sufficiently even, and the finish coating is somewhat plastic; for example - under linoleum or cork floor. Marmoleum can be laid directly on the screed without a subfloor.

Important: remember that after the concrete has set, it must be dried for at least 40 days at room temperature.

On a flat dry screed

The room is thoroughly swept and vacuumed. The floor is treated with bituminous varnish or parquet mastic, diluted five times with solvent or kerosene (primerization). When working, windows are wide open, they work in a respirator-petal, and in the apartment completely, having unscrewed the plugs or turned off the machine on the floor panel, they remove the power supply: there is no need to explain what a spark is in air saturated with vapors of an organic solvent.

Plywood 8-18 mm is pre-cut into squares a quarter of a standard sheet (1250x1250 mm) or stripes. Lay apart, i.e. with a shift: there should not be four seams converging at one point. Sheets are cut with a jigsaw or a manual circular saw - this can be done in the next room an hour after priming. When cutting, it must be borne in mind that a gap of 20-30 mm should remain along the perimeter of the room.

Then the sheets of plywood are laid out on the floor, “dry”, adjusted and numbered without fastening. How to fix plywood to the base floor in this case? Under linoleum or cork, you can simply use glue such as bustilat or parquet mastic, without mounting slots - you get a floating subfloor. The ends of the sheets must also be glued.

Under ordinary oak or parquet similar in properties, plywood, along with gluing, is fixed with self-tapping screws 4-5x60 mm in dowels. In this case, sheets / strips must be laid out with mounting slots of 2-3 mm; For this, it is convenient to use halves of toothpicks:

Note: as a screwdriver insert for a drill, it is convenient to use the insert of a combination screwdriver (see figure above).

On concrete on logs

Under a laminate, inlaid parquet or parquet made of fine wood, plywood is laid on a concrete base on. The same is done if the stability of the temperature and humidity conditions in the room is in doubt. The device of the draft plywood floor on the logs is clear from the figure, we will give only the necessary explanations:

Boards for lags take unplaned 100 mm ("weaving").
Boards for lags can withstand at least a week in the room where they will be used, after which they are culled: those that are warped by an arc are put on the bosses, and those that have been driven by a screw are completely rejected.
Plywood is taken by FK or improved independently, with a thickness of at least 12 mm; better - 18-20.
The preparation of the base floor is done in the same way as in the previous case.
Lathing of logs is made in increments of 300-600 mm so that all edges of the plywood sheets fall on the logs.
Sections of the crate are filled with polyurethane foam or other hydro- and heat-insulating material, but not mineral wool- from it, microscopic needles will inevitably appear in the air, irritating the respiratory organs.
Plywood sheets are laid with a mounting gap of 2-3 mm and with a gap around the perimeter of the room of 20-30 mm.
Attach plywood to the joists with liquid nails glue and fix with nails; fastening with self-tapping screws in this case does not noticeably improve the quality of the subfloor, but it is more expensive.

Note: recently, tongue-and-groove plywood 12-20 mm thick has appeared on sale especially for subfloors. It is produced in the form of sheets from 300x300 mm and strips from 300x600 mm. For a floor made of valuable parquet, this is the preferred option: the cost of a subfloor in this case will still be an insignificant fraction of the total cost of materials, and the likelihood of moisture vapor leaking from under the bottom is reduced by an order of magnitude.

Repair of wooden floors with plywood

Plywood is an excellent material for repairing cracked wood floors that are cracked and creaky. In this case, plywood is laid on a wooden floor in whole sheets from the door so that the most walked surface is solid. Scraps are allowed along the edge and into places under furniture. The plinth is removed as carefully as possible and then it is put back.

Plywood is taken from 12 mm thick. Installation is done with the usual gap of 20-30 mm around the perimeter, but without mounting gaps between the sheets. Sheets are laid on bustilate, liquid nails or any other mounting adhesive; the ends are also glued.

Such a floor made of “self-improved” plywood, painted with any floor enamel, lasts 20 years or more in the bedroom. But it is impossible to repair damp, swollen floors with plywood, with traces of rot and mold, and in rooms with biting biting on the walls is impossible. It is necessary to remove the old floor, look for and eliminate the source of moisture, and only then lay a new one.

Warm floor on plywood

Under plywood, they are laid on a concrete screed on a mounting grid with waterproofing on the base floor. There is one caveat here: the edges of the waterproofing film must be brought under the plinth. If they are muffled with a screed, then the evaporation from heating can concentrate in one place and cause delamination from moisture.

When installing a subfloor under a warm one on the logs, such a problem does not arise, but it makes no sense to complicate and increase the cost of work: a warm floor dries the room well. So it's easier to leave a kind of vent around the perimeter for water vapor.

Plywood innovations

Plywood flooring is a branch of construction engineering that seems to be far from over. In the age of composites and nanotechnology, the good old plywood does not retreat and finds new uses for itself.

Adjustable floors

These floors are used as a base for wood inlays and other fine, exclusive work. Plywood flooring - double, made of high quality plywood. In the sheets of the lower layer there are threaded sockets for bolts. The bolts are shaped: above the thread there is a flat flare in the form of a press washer, and above it is a neck 3/4 of the thickness of the sheet for a hexagon or with a cross slot.

The top sheet with holes for the necks of the bolts is placed on the bolts screwed into the bottom sheet, and adjusted with an open-end wrench or a screwdriver. When using bakelized plywood, the accuracy of the overall surface is quite machine-building.

Plywood parquet

But plywood parquet is an invention of craftsmen. In it, the forgotten art of plywood sawing was revived at a new level. The technology of plywood parquet is simple and accessible to anyone.

Plywood is a durable, multi-layer material made from natural wood. Physical and mechanical properties and specifications plywood is conditioned by the process of its production. Namely, an odd number of sheets of thin wood veneer are glued together with glue.

Veneer sheets are arranged in such a way that the direction of the wood fibers is perpendicular to each other. This makes the plywood very resistant to breaking, stretching and chipping (see table below).

Due to such parameters and affordable cost, plywood flooring is often used in construction.

Bending strength of plywood

Specification for plywood - table

Birch, coniferous, laminated and combined
(TU 5512-001-44769167-02 and TU 5512-002-44769167-98).

It should be noted that due to the fact that plywood for a long time remained almost the only material available to our compatriots, it was used everywhere. This, in turn, gave rise to various kinds and types of plywood.

Varieties of plywood

Types of plywood are determined by the scope of its purpose:

construction;
furniture;
structural;
industrial;
packaging.

Types of plywood depend on the glue used in the production:

FC- waterproof plywood. In its manufacture, kabamide glue is used;

FSF- plywood of the increased moisture resistance. Here, veneer sheets are glued together using phenol-formaldehyde glue;

FBA- plywood is waterproof. In this case, albumin-casein glue was used to glue the veneer. FBA plywood has a slight moisture resistance, but is very much appreciated by those who bring the environmental friendliness of the material to the fore;

FB- plywood, which, thanks to the use of bakelite varnish, can be used in especially humid conditions and in water.

And these are just the main types of plywood. There are many more levels of classification, depending on the thickness of the sheet, the number of layers, the type of wood, the grade, the degree of finish and the type of additional processing.

1. Using plywood for flooring "+" and "-"

Advantages of plywood:

plywood, unlike OSB and fiberboard, refers to natural materials, and not recycled production waste. Therefore, it is more environmentally friendly;

plywood moisture indicators are in the range of 12-15%;

plywood takes the brunt of variable loads. Thus, the screed retains its integrity, and the wood gets microcracks. However, they do not affect the quality of the floor;

due to the fact that plywood is made from wood, it is in better contact with floor coverings. As a result, the service life of the latter increases;

plywood makes it possible to obtain a floor that will meet the specified characteristics (flatness, surface quality) with less time and resource;

laying plywood on the floor does not require special preparation and can be done in several stages;

plywood plays the role of a kind of insulation, allowing you to reduce heat loss through a concrete screed and floor slabs;

with a significant difference in height across the floor, the use of a screed is not recommended due to heavy weight and cost. But plywood, on the contrary, would be ideal;

depending on the grade and quality of polishing, plywood can be used for sub-flooring and finishing.

But:

plywood is not suitable for rooms with a significant temperature difference (for example, for cottages or houses not permanent residence), as well as high level humidity (in the bathroom, bath, sauna, pool).

2. What kind of plywood to lay on the floor

To begin with, it is worth clarifying two important factors.

First moment - What type of floor is plywood for?. After all, the floor, in fact, is a two-layer structure, which consists of a draft (lining) and a finishing (front) coating layers.

Second moment - in which room to lay plywood. So, for example, in a residential area, and even more so in a bedroom or a children's room, it is permissible to use only FK brand plywood. It does not contain formaldehyde. Therefore, its use is absolutely safe, with satisfactory indicators of moisture resistance. AT industrial premises with good ventilation, it is permissible to use FSF plywood. But only 1 emission class. The class means that the formaldehyde content does not exceed 100 mg. per 1 kg. plywood sheet.

Depending on the above points, the question of which plywood is better for the floor (which one to use for the floor) will be decided.

3. What kind of plywood to choose for the floor

When choosing plywood for the floor, you should pay attention to the following parameters:

brand of plywood. As already noted, for residential premises it is better to purchase plywood of the FC brand. Its moisture resistance indicators fully meet the operating conditions in residential premises;

plywood class(emission class). Only class E-1 is suitable for the floor;

type of plywood for the floor. Plywood is divided into 4 grades. In this case, the sides of the sheet may have a different grade. It is marked like this 1/1, 1/2, 2/2, etc. Plywood of 3 and 4 grades is suitable for the subfloor. For finishing - 1 or 2 grade;

plywood moisture. A sheet with a moisture index of 12-15% is of high quality;

number of layers of plywood. The thickness of the veneer in a plywood sheet is from 1.7 to 1.9 mm. Therefore, their number determines the thickness of the sheet. The more layers a sheet has, the more durable it is. However, the thickness of plywood is selected taking into account its purpose. So for the subfloor you need plywood 12-18 mm thick, for finishing 10-12 mm. When using plywood in production - at least 25 mm. Please note that if the plywood is to be laid in two layers, then the thickness of the sheet must be divided by two;

plywood manufacturer. European or domestic manufacturers offer material good quality. But Chinese-made plywood causes criticism from users and often does not meet the stated characteristics.

4. Laying plywood on the floor

4.1 Subfloor plywood

Laying a plywood subfloor is the fastest, most affordable and easiest way, which also has several varieties.

.
Sheet thickness 10-12 mm. glued to the base. It is used when there is an even concrete screed normal quality. The main thing is not to forget about expansion joints when laying. The gap is 3-4 mm. between the sheets, as well as between the sheet and the wall, will allow the plywood to play and adapt to the surrounding conditions.

This method of installation can be applied with a height difference. It is enough to use special fasteners.

Adjustable floors from plywood do not require the installation of a log, and the height difference is leveled by fasteners located under the plywood.

The material was prepared for the site www.site

Laying plywood on logs or floor beams.

Plywood, thickness over 12 mm. attached to the prepared base. The method is laborious, usually used when it is necessary to insulate the floor or raise it to a certain height.

allow you to install a sheet of plywood so that it can compensate for the difference in height across the floor.

Quite common is the situation when partially lost appearance, but nevertheless do not cause complaints. Then the floor covering is laid on top of them.

But, so that the finish coating does not become unusable, an intermediate floor (in this case, plywood) should be laid on the boards, which will level the surface.

Laying plywood on a wooden floor is carried out using hardware and is characterized by simplicity and high speed of work.

In order for plywood laid under laminate, under linoleum or to perform its functions for a long period, you must adhere to the following installation rules:

securely fasten all sheets, taking into account deformation gaps;

caps of hardware "drown" in the sheet;

remove irregularities with a grinder;

to putty grooves and cracks;

lay the underlay.

But laying plywood under a wooden floor is absolutely not required. Due to the massiveness of the floorboard, it can be laid on logs or on a flat concrete screed.

4.3 Finished plywood floor

Craftsmen can create a real palace parquet from plywood. In this case, special requirements are put forward for the quality of plywood. It is allowed to use only the first grade, the surface of the front side of the sheet must be polished. To create a beautiful pattern, plywood is stained, and the laid plywood parquet is sanded and opened with several layers of parquet varnish.

5. Floor plywood - protection, operation and storage

In order for the plywood floor to serve you faithfully for a long time, you need to provide protection for the sheets even at the installation stage. When working with plywood, you need to consider:

plywood needs acclimatization. Only purchased material should not be used immediately. He needs to be given time to lie down in the conditions in which he will be operated.
The exposure period depends on where, how, in what position, at what temperature regime and moisture level plywood was stored. The acclimatization period can be:

day. If the difference in temperature and humidity between the place of sale and installation is minimal, and the sheets have been stored in a dry room, flat surface in a horizontal position;

3-5 days. If the difference exceeds 5-8°C and 10% (temperature and humidity, respectively);

over a week. If the deviations are significant or the sheets are slightly deformed. The latter is eliminated by pressing down the stack with weights and using more hardware per 1 sq.m. sheet.

dampness destroys plywood. Humidity fluctuations can cause serious damage to the wood from which plywood is made. At the same time, constant humidity in the room cannot be higher than 70%, and short-term - 80%. Laying plywood on a wet base is unacceptable. To check the moisture level of a wooden base, use a special device. And the concrete is covered with a film for a day. The presence of condensate under the film indicates that it is worth delaying the installation of plywood;

plywood sheets are laid at a temperature of 20-30 ° C. In this case, the sheet is in optimal conditions for itself;

additional processing improves the performance of plywood. So, for example, an antibacterial primer will protect the sheet from the effects of fungi and microorganisms. Impregnation with PVA-based putty will increase its moisture resistance. And the application of acrylic varnish will increase the strength of the surface layer.

Conclusion

Having familiarized yourself with the types and types of plywood for the floor, as well as with the nuances of its selection, storage and laying rules, you can say with confidence which plywood is best suited for flooring.

The floor from the boards is durable, environmentally friendly, resistant to abrasion. However, after several decades, the boards begin to creak, dry out or rot from the high humidity in the room. If you lay linoleum or carpet on an unprepared plank floor, lay a laminate or parquet, then the surface will not be perfectly flat. All defects in the rough base will be visible through the final fine coating, and in the case of locking systems, installation will not be possible if uneven.

To make the floor high-quality and durable, under flooring underlay needs to be installed. For this, sheets of plywood are suitable, which will hide all the bumps and imperfections of the wooden floor.

Peculiarities

To choose plywood for leveling the floor, you need to understand the features and classification of the material on the market. Plywood differs in grade, thickness, moisture resistance and material of manufacture.

The main characteristics will help you choose the right sheets.

There are 4 grades of plywood that can be distinguished visually:

The fourth grade has defects on the surface, rough, there are holes from knots, since the lowest quality raw materials are used for manufacturing.
The third grade is better than the previous one and there is less marriage on the surface.
The second grade has minor cracks, smooth.
The highest quality and most expensive first grade is well polished, all sides are free of defects.

When choosing a variety, they are guided by price and quality. For the construction of the subfloor, plywood of the second and third grades is suitable. According to the processing method, there are:

Unsanded plywood.
Sanded (one or both sides).

For installation on the floor, one-sidedly ground material is taken, laying smooth side upstairs.

Plywood is made from hardwood and coniferous wood (most often from pine and birch). Wood veneer is bonded together with natural and synthetic resins. The top layer can be treated with a lacquered water-repellent compound.

According to resistance to moisture in residential premises, brands are distinguished:

In bedrooms and other living rooms with low humidity, FC and FBA brands are laid, made on the basis of carbamide and albumin-casein glue. They differ in environmental friendliness and average resistance to moisture.

The FSF brand is placed in the corridor and in the kitchen, where greater moisture resistance is needed.

The thickness of the canvas determines the number of layers of veneer. Their odd number is laid perpendicular to the previous one, creating a durable building material. For subfloor flooring, plywood with a thickness of 10 mm or more is taken.

Plywood lends itself well to fastening with self-tapping screws, does not crumble or crack.

The analogue of plywood in the construction market is OSB - oriented strand board. Such materials have similar properties, but differ only in production. For plywood, wood veneer is the raw material, and for OSB, wood chips are processed with natural resins.

OSB is divided into different categories:

The first is suitable for minimal stress and dryness.
The second - is made for impenetrable residential premises.
The third one is characterized by high moisture resistance and durability.
Fourth - used in the construction of walls.
Lacquered or laminated - coated protective layer varnish or laminate.
Grooved - at the joints has a connecting groove.

The best solution for the subfloor will be OSB 3, grooved and easy to install. Such sheets are produced with a thickness of 0.5 cm to 4 cm.

Pros and cons

When it is difficult to decide which substrate is better: plywood or chipboard, you need to consider the advantages and disadvantages of each material. plywood cover has the following advantages:

Withstands heavy loads.
Light weight.
It is flexible, has high bending strength and deformation.
There is no foreign chemical smell.
High leveling ability.
Easy to handle, saw.
Easy to operate.
Smooth beautiful outer surface.
Keeps the heat in the room.

Advantages of using oriented strand boards:

Affordable.
They don't flake off.
Surface without defects.
Various sizes.
The panels are lightweight.
Resistant to harmful insects.

But all wood materials have a common drawback - moisture has a great influence on them. Humidity will quickly destroy wood raw materials, so it is better to lay moisture-resistant brands of coatings. The reverse negative side of moisture-resistant panels is environmental friendliness. They emit formaldehyde, which is harmful to health, but it is he who helps fight moisture.

Both leveling materials have a high degree of ignition from open flames, therefore, before laying the material, care must be taken to increase the fire retardant properties.

If you lay the flooring on the logs, then up to 10 cm in the height of the room disappears. This is not always acceptable in certain situations. To lay the sheets, it is necessary to make a clear calculation so that there is no waste and unnecessary work on alteration. It is recommended to fasten these materials with self-tapping screws with an average pitch of 20 cm.

Such sheets tolerate fasteners well and are tightly attracted.

The differences in price between plywood and OSB of the same brand are not the most significant, but OSB is cheaper. In suitable and unpretentious conditions, you can lay OSB boards, but plywood is suitable for a durable wear-resistant coating.

Materials and tools

Plywood and OSB are similar in laying technology. To cover the floor with wood sheets, use the same installation tools. Mounting materials are the same. In order to quickly and efficiently lay plywood sheets on a rough plank floor, you need to stock up on basic construction tools. The work will require:

Level for measuring the evenness of the floor.
Screwdriver or screwdriver for screwing screws.
Drill for drilling holes for dowels.
Roulette for measuring the required length.
Jigsaw or hacksaw for sawing plywood sheets to the desired dimensions.
Sanding attachment on a drill or grinder for grinding joints between sheets.
Roller or paint brush for applying primer.
Broom or vacuum cleaner for garbage collection.
Spatula for applying glue.
Hammer for nailing.

To improve the moisture-resistant and fire-retardant properties of the material, it is advisable to use special flame retardant compounds and primers.

It is better to lay plywood or OSB on water-dispersion glue bustilat, PVA. These grades are suitable for gluing wood surfaces. They are safe for health, have no smell and dry within a day. The adhesive is easily applied with a spatula or brush (depending on the consistency).

You can fasten plywood sheets on self-tapping screws and nails. If the laying of materials is carried out in an apartment, it is preferable to use self-tapping screws with dowels, since working with a drill and a screwdriver is easier and quieter than a hammer with nails.

Preparatory work

Before starting the installation of plywood on a wooden floor, the main preparatory work. First, an assessment is made of the original rough wooden base. Visually assess the condition of the floorboards, the presence of ill-fitting and creaky floorboards.

Check the construction level for differences and uneven surfaces.

Then the skirting boards are removed. All loose boards must be additionally fixed with nails or self-tapping screws to the lower beam. Floorboards affected by the fungus are replaced or cleaned, impregnated with an antifungal compound. Warped and damaged boards must be replaced. The protrusions on the surface are cut off with a planer and polished. Slots and cracks are filled with sealant or glue.

After the repair, garbage, sawdust and dust are cleaned with a broom or a vacuum cleaner. The untreated plank floor is treated with an antiseptic. Roll material can be laid under the plywood floor as noise insulation and insulation.

Penoplex or isolon of small thickness is suitable for the substrate. Connect the strips of the substrate to each other with construction tape.

The plywood is fastened after drying to avoid deformation. To do this, the material is brought into the room and left for 2-4 days. The optimal solution to protect against moisture and fire, both sides of the panel will be treated with a primer or acrylic varnish. The technology of laying wood sheets requires an indent from the wall in the amount of 1-1.5 cm between sheets up to 0.5 cm.

This must be taken into account when cutting and laying plywood blanks on the floor.

To relieve stress from the material during operation and ease of installation, the sheet is cut into 4 parts using a jigsaw. All parts are preliminarily placed and adjusted, the layout is drawn and the workpieces are numbered. Lay the sheets with an offset to reduce the number of joints and avoid crossing.

If you follow all the rules when laying plywood, it will serve as a high-quality, durable base for any floor covering. Finishing decorative material you can re-lay, and the plywood base will remain the same.

Alignment methods

The leveling method depends on the evenness of the subfloor. Differences in height of more than 1.5 cm suggest plywood flooring along the logs. Minor irregularities are covered with plywood directly on the wooden floor.

Boards with a difference of less than 1 cm are aligned with supports in the right places. As a support, thin squares, bars of wood or plywood are used.

Laying plywood on the floor can be done with or without underlayment. The lining roll is rolled out over the entire surface and fastened with adhesive tape. Plywood material is spread on top in accordance with the scheme, the evenness is checked and fixed with self-tapping screws. In this case, sheets with a thickness of 1 cm are needed.

Without the use of gasket material, an adhesive fastening method is used. A small area of the room is covered with glue for 2-3 mm, starting from the corner. A sheet of plywood blank is superimposed on top and pressed tightly. Additionally, you can screw a few screws for better fixation. This method is used to install the rest of the room.

Laying birch plywood does not require special skills and can be done by hand.

When a plywood sheet does not lie flat, bends, there are slight differences in height with other blanks, supports are used. Anchor points are placed in ill-fitting places and fixed through with self-tapping screws.

If on wooden base lies fiberboard, then dismantling is carried out if the material is old, warped from moisture, crumbles and exfoliates at the edges. Fiberboard is not recommended to be laid on the floor, since the sheets deteriorate from moisture and have poor leveling properties due to their small thickness.

To level significant fluctuations in height, use logs. As a log, boards of the required length with a section of 3-5 cm by 7-10 cm or coniferous plywood slats of the same size are used. The location of the lag depends on the thickness of the plywood and the load during operation. Small thickness requires a smaller distance between the lags, starting from 40 cm. You should not use sheets less than 1.5 cm in height. The installation of the log is designed in accordance with the layout of the plywood in the room, so that the joints are laid in the middle of the timber.

The horizontal installation of the lag is measured by a water or laser level. The evenness of the entire floor depends on the accuracy of installation. The lags are attached to the glue and screwed with screws. Bars are placed perpendicularly between them, obtaining a reliable crate, on which plywood blanks are laid.