How to make a floor from plywood on logs yourself. Laying plywood on a wooden floor Which is better floor batten or plywood?

Leveling floors before roughing and finishing is directly dependent on the height and area of ​​the room. But this process is also influenced by several other factors. What kind of flooring will be, in what temperature and humidity range the floor will be located, how much is planned to be spent on finishing work, what are the relations of residents in aggressive adhesives and solutions, etc. All of the above questions make the choice of material for leveling the floor not so easy. To date, what home-grown builders and recognized repairmen have not tried! Here we will talk about plywood, which is an excellent material for flooring in residential and non-residential premises. Plywood sheets of various thicknesses and formats are used both for rough finishing before laying laminate, linoleum or parquet, and for finishing the floor 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 recyclable 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 residual wood mass and liquid binder. Each plywood sheet consists of several layers of the working tree. And due to the fact that these layers have multidirectional fibers, the floor is durable and reliable. You can read about what this is in the article.

About how much 1 sheet of moisture-resistant plywood costs from this

Plywood flooring has three main objectives.

1. "Smoothing" irregularities and preparation for finishing coat.
2. Providing the required level of thermal insulation.
3. Protection of parquet boards 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. Plywood is placed either directly on the floor, or raised above it with the help of lags - special beacon bars.

What are the technical characteristics of moisture-resistant plywood, you can find out from this

The video shows the thickness of the plywood on the floor:

Methods for laying sheets on the floor

Put on lags

If the differences in height on the floor are quite significant (from 5-10), then the plywood can be put and fastened to special logs. They not only allow you to achieve a perfectly flat floor, but also provide an air cushion for thermal insulation and waterproofing, and then it is easier to select another 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” up to 10 cm of the height of the room.

Manufacturers and prices

When choosing a finishing coat, 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 characteristics of the room. Depending on the tasks, different types of plywood and their thickness are used. If you are just looking at the material, it is useful to know and.

You can view the photo of OSB plywood in this particular

In each specific case, an assessment of the needs for a particular type should be done by a professional.

03.11.2009, 19:27

08.11.2009, 08:33

The golden floor will turn out with 30-40 plywood.
I'm thinking of filling 25 boards with a gap, and on top for leveling plywood mm 3-6. Between the joists and the planks, as well as between the planks and plywood, I'm going to put a soft material like jute or flax for soundproofing and to avoid squeaking.

08.11.2009, 12:41

08.11.2009, 13:01

2andre777
what decision was made?

Plywood or board? but then I myself can not decide, csp or floorboard?

08.11.2009, 15:40

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

I chose a board, throwing away the cheap version of the forty + plywood, since it will be mercilessly and doubtful about the strength to deflection by a point load.
DSP somehow did not think, all the net and the material is fragile and heavy and it is more difficult to work with it, I thought of its current under the tiles of the bathroom on the 2nd floor after the board ... or GVL ..

08.11.2009, 18:26

That's why forums are needed!

Thank you for helping to lean towards the same option, i.e. 40mm board (beams pitch 600), and central heating unit under the warm floor and under the tiles in the bathroom ...

11.11.2009, 14:26

boards 25 on the floor ??? but not enough?
What is the distance between the lags we are talking about?
"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 planned the distance between the lags - half a meter. The 25 mm board fits right here. But if the topikstarter, with its 40 mm, takes a distance between the lags of 1 meter, then it 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 it 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 too much, 25 will be enough. As a last resort, take 30.

12.11.2009, 09:19

I chose a board, throwing away the cheap version of the forty + plywood, since it will be mercilessly and doubtful about the strength to deflection by a point load.
Flexural strength? Durability is provided by the board. 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 a board. There are no more connections-sources of squeak. Moreover, I am going to lay the boards with a gap, i.e. they will not touch and they will not be able to squeak. And in any case, it is advisable to lay with soft material. When someone walks in cocks, the sound will spread throughout the house. So that it is jammed, and you need to lay horizontal joints with soundproofing. And with such a gasket, a creak is generally impossible.

And further. You are a floorboard for 12 stitches. still tortured to lay. There, first you need to lay it evenly, then wedge it. After a year, when the boards are dry, wedge again. This does not guarantee that after the supply of heat, this entire household will not dry out again with the appearance of cracks and creaks.
My version in this respect is much less laborious.

12.11.2009, 10:17

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

12.11.2009, 10:31

Your version looks more technologically advanced)))
and how much will the m2 cost in your case, excluding the soft pad and floor covering? and what kind of gasket do you suggest to use? I only remembered foamed polyethylene. with a thickness of 4-5 mm, this is a penny ...

At a cost of 12 tons per cube of 40mm floorboard, m2 is 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 really against it? Who likes what. It's just that my version is more budgetary. But everyone chooses for himself based on his needs.

12.11.2009, 11:15

and how much will the m2 cost in your case, excluding the soft pad and floor covering?
Count it. Our cube of scraped lumber costs 4 tr. If you take a board of 30, then you get 120 rubles per square meter per board. Plywood 6mm FC birch costs about 230 rubles per sheet, i.e. 100 rubles per sq.

And what gasket do you suggest to use?
After assembling the log house, I still have a lot of jute tapes. I will use it. Besides, I like it better than the foamed plastic.

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

12.11.2009, 11:38

And for some reason you do not take into account the final flooring in the price. This I mean that making the floor at once is no more expensive than building a subfloor, and laying the topcoat on top.
In my apartment I am laying laminate on plywood out of bezishodnost, there would be options, I would lay a normal floor

12.11.2009, 11:58

What is the final coverage?
Plywood can be varnished in the same way. The texture will remain no worse, there will be fewer seams, it will be smoother, stronger, etc.

12.11.2009, 12:25

Flexural strength? Durability is provided by the board. Plywood is just for the smoothness of the floor.
I'm talking about strength under load, for example, a sofa leg, it will press on the plywood and one (!) board under it, i.e. adjacent boards do not participate in the work by distributing the load.

12.11.2009, 12:48

Don't you think that the same sofa leg will press more than two boards, even if they are fastened with a thorn? The spike does not distribute the load very much. 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 ... sometimes, it would be interesting to see. How will you do it, post pictures pliz

12.11.2009, 13:44

It seems to me that you are confusing plywood with paper. : lol:
In this respect, the two-dimensional surface of the plywood is much more efficient in distributing the load than the one-dimensional tenon. Despite the fact that the thickness of the tenon and plywood are comparable.
but the thorn is shorter. and plywood - to the nearest board ... with what gap is there a board?

12.11.2009, 14:27

I was talking about varnished plywood. But with dyed it is even easier. Just a perfect one-color flat surface is obtained, on which even the seams can hardly be guessed with a good putty.

12.11.2009, 14:42

but the thorn is shorter. and plywood - to the nearest board ... with what gap is there a board?
The gap is 2-5 mm.

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

Now another experiment. Stretch the tape and place the ball in its center. Did you see how the load was 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 thorn. I don't know what the ultimate strength will be, but it is unlikely to exceed several Pa (NOT MPa). For plywood in all directions, this parameter is the same, 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 a 7.5-meter run made of plywood with a height of 45 cm. When it is warm, I will glue it.

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

12.11.2009, 14:55

if you put 30 side by side. and if without a thorn and a gap ...
And you count like this. You have a weaving floorboard. on both sides a 5 mm spike and groove, which do not work like a 30-ka board. 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, I am confused by the fact that the edged board is mostly damp and not quite the same thickness, you have to pick it up, and if you buy a ready-made floorboard (450-500 r / m2), then I will accept each one upon purchase and put it (hopefully) without any problems. The problem is different, after the floor there will be gL partitions 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

Putty on wooden floors is a last resort. Nafig falls, the wooden floor walks and vibrates. Changes geometry depending on humidity and temperature.

12.11.2009, 16:19

Well, I am confused by the fact that the edged board is mostly damp and not quite the same thickness, it is necessary to select
It depends on the office. We have one set up some kind of disk sawmill, so they have a flat board, almost like a planed one. The price is the same as others. They are just located in a village 20 km away. away from the city, so they are spinning to compete with the intracity ones.

The problem is different, after the floor there will be gL partitions 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 thing. This is also the reason why I want a simple board with gaps.
Well, if you really really want a floorboard, then you need to first make partitions, and then lay the floors in order to wedge them in each room separately. As I understand it.

12.11.2009, 16:29

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

Each idea has its advantages

Edged board + plywood or csp:
- better sound insulation (two damping layers, three can be used)
- versatility (laminate flooring, tiles, etc.)
- no creaking, rubbing structures
- does not require wedging when dry
- you can lay a film warm floor
- the price depends on your delights, either a sale laminate or an elite parquet

Batten:
- 100% natural, excluding varnishes, etc.
- no need to bother with the choice of laminate, choose the color of the varnish and that's it ...
- cheaper, cheapest option

Everything seems to be, i.e. the floorboard has one serious plus - this is the price with a decent, albeit country-style view

13.11.2009, 06:39

Well, if you really really want a floorboard, then you need to first make partitions, and then lay the floors in order to wedge them in each room separately. As I understand it.
Well, such a torment in the bathhouse: D there will be too much waste floorboard, I want to - put it and forget: D
I think maybe another option is to calculate, spread 4 mm plywood and on top of a 30 mm tie on a wire mesh (as a reduction in cost), pull it crosswise across the nails and pour ..: shock:

20.11.2009, 20:19

I did it like this:
Beam 10x10 beams, the distance between the beams is 60 cm. I bought an unedged board 30, sanded it and laid it on the floor with self-tapping screws.
Then he put a 3 mm isolon. and put 20mm chipboard on top. (after priming it). I also planted chipboard on self-tapping screws.
I threw linoleum from above, as a result, nothing creaks and does not bend anywhere.
Here is a photo

20.11.2009, 21:49

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

21.11.2009, 12:59

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

Warming and so as not to "creak" (when the chipboard deflects so as not to come into contact with the board). This is the first floor, I will do the second floor as well, but instead of chipboard I will put 15-20 mm plywood. Let it be more expensive, but more environmentally friendly.
By the way, a friend put a 5 mm isolon. and on top of a 9 mm OSB board. he has noticeable dips during the walk because of the thick isolon.

21.11.2009, 13:17

How are you not afraid to lay chipboard at home, and even not laminated ?! You can still look at the particle board (if available on the market), the same particle board only without phenol and other cement-based chemicals. You also need to be careful with plywood, most manufacturers save on our health.

The plank floor is durable, environmentally friendly, and abrasion resistant. 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 laminate or parquet, then the surface will not be perfectly flat. All defects of the rough base will be visible through the final finishing coating, and in the case of locking systems, installation will not be possible if uneven.

To make the floor high-quality and durable, you need to lay a substrate under the flooring. For this, plywood sheets are suitable, which will hide all the irregularities 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 types of plywood that can be distinguished visually:

• The fourth grade with defects on the surface, rough, there are holes from knots, since the lowest quality raw materials are used for production.
• The third grade is of higher quality than the previous one and there is less waste on the surface.
• The second grade has slight cracks, smooth.
• The highest quality and most expensive first grade is well polished, all sides are free from 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, the following are distinguished:

• Unsanded plywood.
• Sanded (one or both sides).

For floor mounting, take one-sided sanded material, placing the smooth side on top.

Plywood is made from deciduous and coniferous species of wood (more often from pine and birch). Wooden veneer is held together by natural and synthetic resins. The top layer can be treated with a varnished water-repellent compound.

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

In bedrooms and other living rooms with low humidity, FK and FBA brands are laid, made on the basis of urea and albuminocasein glue. They are environmentally friendly and moderately resistant to moisture.

The FSF brand is placed in the corridor and in the kitchen, where high moisture resistance is required.

The thickness of the leaf is determined by the number of veneer layers. An odd number of them are stacked perpendicular to the previous one, creating a durable building material. For subflooring, plywood with a thickness of 10 mm and above 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 used as 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 low-pass residential premises.
• The third is characterized by high moisture resistance and strength.
• The fourth is used in the construction of walls.
• Varnished or laminated - covered with a protective layer of varnish or laminate.
• Grooved - has a connecting groove at the joints.

The best solution for a subfloor would 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 covering has the following advantages:

• Withstands heavy loads.
• Low weight.
• It is flexible and has high bending and deformation strength.
• There is no foreign chemical smell.
• High leveling abilities.
• Easy to handle, cut.
• Easy to operate.
• Smooth, beautiful exterior.
• Retains heat in the room.

Pros of using oriented strand board:

• Affordable.
• Do not delaminate.
• The surface is free from defects.
• Various sizes.
• The panels are lightweight.
• Resistant to harmful insects.

But all wood materials have a common drawback - moisture has a big effect on them. Moisture will quickly destroy wood raw materials, so it is better to lay moisture-resistant coatings. The reverse negative side of moisture-resistant panels is environmental friendliness. They release formaldehyde, which is unhealthy, but it helps fight moisture.

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

If you lay the flooring on logs, then it disappears up to 10 cm in the height of the room. 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 alteration work. 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.

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, OSB boards can be laid, but plywood is suitable for a durable wear-resistant coating.

Materials and tools

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

• Level for measuring the evenness of the floor.
• Screwdriver or screwdrivers for screwing in self-tapping screws.
• Drill for drilling dowel holes.
• Tape measure for measuring the required length.
• A jigsaw or a hacksaw for sawing off plywood sheets to the desired size.
• Grinding attachment for a drill or grinder for grinding the joints between sheets.
• Roller or paint brush for applying the primer.
• A broom or vacuum cleaner for cleaning up rubbish.
• Spatula for applying glue.
• Hammer for hammering in nails.

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

It is better to put plywood or OSB on water-dispersion glue bustilat, PVA. These grades are suitable for bonding wood surfaces. They are safe for health, odorless and dry within 24 hours. The adhesive can be easily applied with a spatula or brush (depending on the consistency).

You can fix plywood sheets with 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 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 is carried out. First, the initial rough wood base is assessed. Visually assess the condition of the floorboards, the presence of poorly fitted and creaky floorboards.

The differences and unevenness of the surface are checked at the building level.

Then the skirting boards are dismantled. All loose boards must be additionally secured with nails or self-tapping screws to the lower beam. The floorboards affected by the fungus are replaced or cleaned by saturating them with an antifungal compound. Deformed and damaged boards need to be replaced. The protrusions on the surface are cut off with a plane and sanded. Gaps and cracks are filled with sealant or glue.

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

Penoplex or izolon 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. For this, the material is brought into the room and left for 2-4 days. The optimal solution for protection from moisture and fire is to treat both sides of the panel 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 the 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 laying, the sheet is cut into 4 parts using a jigsaw. Pre-place and fit all parts, draw an arrangement diagram and number the workpieces. It is necessary to lay sheets with an offset in order to reduce the number of joints and avoid overlapping.

If you follow all the rules when laying plywood, it will serve as a high-quality, durable base for any floor covering. The finishing decorative material can be re-covered, but the plywood base remains 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 joists. Minor irregularities are covered with plywood directly on the wooden floor.

Boards with a drop of less than 1 cm are leveled with supports in the right places. Thin squares, wood or plywood bars are used as a support.

Plywood can be laid on the floor with or without a backing. A roll of lining is rolled out over the entire surface and sealed with tape. Plywood material is spread from above in accordance with the diagram, evenness is checked and fixed with self-tapping screws. In this case, sheets with a thickness of 1 cm or more are needed.

The adhesive method of fastening is used without the use of cushioning material. A small area of ​​the room is covered with 2-3 mm glue, starting from the corner. A sheet of plywood blank is superimposed on top and pressed tightly. Additionally, several screws can be screwed on 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 the plywood sheet does not lie flat, bends, there are slight differences in height with other blanks, supports are used. Anchor points are placed in poorly adjoining places and are fixed through and through with self-tapping screws.

If there is fiberboard on a wooden base, then dismantling is carried out if the material is old, crumpled 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 low thickness.

To neutralize significant differences in height, lags are used. As a lag, 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 lags 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.Do not use sheets less than 1.5 cm in height. The installation of the lag is designed in accordance with the layout of the plywood in the room, so that the joints fit into the middle of the timber.

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

A dry prefabricated floor screed is most often made of plywood sheets. It is believed to be the ideal base for all types of flooring, including linoleum, laminate, carpet and even ceramic tiles. A high-quality and durable plywood floor on logs requires attention to the nuances and adherence to the basic rules specified in SNiP.

Plywood is a multi-layer wood-sheet material that is made by cross-gluing an odd number of peeled veneer layers. For production, birch raw materials or conifers of technical varieties are most often used, less often - oak, beech, linden and others.

Plywood advantages:

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

The disadvantage of sheet material is that adhesives are used for production, which are unsafe for human health. 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 areas 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.

Brand.

This parameter is determined by the type of adhesive used. Let's consider three basic types:

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

Variety.

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

• E - extra or elite. The product is made of oak, alder, birch and other species, has a perfectly flat, smooth surface, there are no slightest defects. A slight deviation in the structure of random wood is allowed.
• I - possible pinned and healthy light or dark knots - no more than 3–5 pcs. for every square meter of surface. Crevices (except for closed cracks) and other types of defects are excluded.
• II - healthy, partially accrete, non-accrete and falling out knots with a diameter of up to 6 mm, wood inserts and open cracks up to 200 mm long and no more than 2 mm wide are allowed.
• III - there are: a) wormholes and holes from fallen out knots with a diameter of up to 6 mm in an amount of no more than 10 pcs. for 1 m² of area; b) open cracks 300–600 mm long and up to 5 mm wide (subject to filling with putties or sealants); c) dents and scallops.
• IV - a surface with all kinds of defects: from intergrown and fallen out 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 degrees of quality is used. Please note: plywood is usually double-marked, such as 1/2 or 2/2. Matches the grade of each side. That is, a product of class 1/3 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 on one side only.
• Ш2 - sanded on both sides.
• NSh - unpolished.

Laying the floor on the joists is done using any kind of slabs. But common sense dictates that it is better to use products that are sanded on at least one side. This will allow you to create the most even and smooth floor for the installation of linoleum, laminate, etc.

Dimensions.

The length of the plywood sheets can reach 6 m, the width is 3 m, and the thickness starts from 3 mm. For roughing and finishing works on horizontal bases, the following material is used:

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

The optimum plywood thickness for the joist floor depends on the type of prefabricated screed and the load level. 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”, a chamber-dried wooden beam is used to form the floor along the logs, moisture content 12–18%, without cracks, bark and traces of rot. In this case, the length of the abutted 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 different parameters: the level of the load, the section of the insulation used, the maximum floor height and even the personal preferences of the customer. There are no universal recommendations, components are selected in each case separately.

For the arrangement of the supporting 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, alder, resistant to moisture changes.

Do not forget that wooden structural elements are not highly biostable. Therefore, they must be treated with fungicidal and hydrophobic agents. This will significantly increase the service life of the entire floor structure.

It would be useful to mention the underlays for the joists. 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 moisture. When installing on a concrete or plank floor, a 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 logs on glued plywood linings.

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

Consider another important component of the floor structure - hardware. In addition to the lags, you will need fasteners to fix them to the base, as well as to attach the plywood sheets to the frame. These can be anchors, nails, universal screws or with self-centering heads, metal corners, etc.

The range of fasteners is huge. To fix the pads or directly the lag to the concrete base, a dowel is 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 slats to the base.

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

Anchoring fasteners for concrete and bricks are made of high quality alloys - brass, stainless steel. 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 cross-section of the sleeve or less than 0.5 mm. When hammering in 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 underlays from 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 from 6 to 12 mm. The length is selected based on the thickness of the log and / or underlays, taking into account the depth of introduction into concrete from 5 cm or more. The approximate spacing between fasteners is 30-60 cm.

To rigidly attach pads or joists to a wooden sub-floor, you can use wood screws with rare threads or universal galvanized with a diameter of 4 mm or more. The distance between the hardware is at least 30 cm, the screw-in depth is from 30 mm.
For attaching plywood to the joists, it is most convenient to use special self-tapping screws for gypsum fiber board and chipboard, or universal galvanized ones. The former differ from the standard ones with a mixed screw thread and notches on a tapered head, 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.

It is not recommended to use black tempered wood screws for plywood on logs. Practice shows that with seasonal changes in geometric dimensions, this type of hardware breaks under load, and the structure “loses” its rigidity.

Ordinary nails with a cylindrical shank 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 a nailer. The product is often targeted at the base or supporting frame - at a distance of 15–25 cm.

Step-by-step instruction

For DIY installation of a prefabricated screed, you will need:

1. Plywood sheets of suitable thickness.
2. Wooden lags.
3. Backing material for leveling the base.
4. Antiseptic primer.
5. Hardware.
6. Sound insulation and / or thermal insulation with accessories.
7. Repair compounds for partial restoration of a damaged base.
8. Waterproofing.
9. Damper tape.
10. Silicone sealant or elastic wood filler.
11. Roulette, marking pencil, metal ruler or rail.
12. Drill / screwdriver or hammer / nailer with accessories.
13. Laser or water level.
14. Spatulas, brushes, rollers.
15. Cutting tool with accessories for wood and plywood (circular saw, jigsaw, etc.).
16. Sanding machine.

The technology for assembling the prefabricated screed is partially presented in SNiP 3.04.01–87 (SP 71.13330.2017) "Insulation and finishing coatings". In accordance with the recommendations of these standards, installation is carried out in 4 stages.

Training

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 gets started without partial repair of damaged areas. Rotten, damaged wood flooring elements must be replaced, and cracks and loose areas of the mineral base must be repaired. To do this, you need to open up the cracks, remove dust and fill with repair compounds. If possible, it is better to clean the 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 residual moisture in the concrete base;
• a cold basement is located under the ceiling;
• 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 waterproofing, the entire available range of materials is used: films, membranes, roll-on glued products, coating compounds, painting agents, 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 joists. If noise-insulating mineral wool (stone or glass) is used, then it must be laid in the openings between the logs, and the support rails themselves must be fixed using point acoustic spacers.

Laying logs on acoustic pads.

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

Formation of the power frame

The lag frame can be formed in the form of longitudinally arranged beams or as a single or double lathing. Of course, the second option creates a more reliable support for the plywood.

SNiP 3.04.01–87 (SP 71.13330.2017) recommends laying the slats across the luminous flux, and in corridors and other rooms 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 across 2-3 elements. Or worse, in between.

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

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

Now you can start installing the lag, observing 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, gaskets made of chipboard, OSB, MDF, etc. are installed under the frame elements.After checking with a leveling level, the bosses or backing boards are attached to the base dowel - nails, self-tapping screws or anchors.

Plywood linings.

Logs on wooden bosses.

To drill holes for hardware in underlay components, logs and plywood, it is worth purchasing feather or special wood drills with countersinks.

Many craftsmen recommend laying damper layers on firmly fixed supports. This preventive measure will prevent the structure from creaking in the future.

The penultimate step is to fix the logs over the entire area of ​​the room using suitable hardware. Please note that a widened strip should be laid in the doorways, which will protrude beyond the partition by 50-100 mm on each side.

For maximum leveling accuracy, you can use fastening and supporting 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 bar is placed and fixed with a lock nut. The excess anchor rod is cut off with a grinder or a metal file.

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 the installation of the lag, a suitable thermal insulation material is placed in the formed "windows": 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 estimated load on the floor (weight of furniture, intensity of foot traffic, etc.), the greater the thickness of the slabs and the smaller the distance between the lags. This will avoid deflection of the structure and its damage.

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

Installation of slabs begins with their preparation. You should cut them to the required dimensions, make cuts for communications or enclosing structures of complex shapes. Then a preliminary placement is carried out. The first row is laid out from the far corner along the solid wall.

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

After one row of plywood has been drilled and the sawdust removed with a vacuum cleaner, the sheets are secured with suitable fasteners. Experienced craftsmen recommend starting to screw in the hardware from the center of the slab, with a gradual movement 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 "sunk" into the plywood by at least 0.2 centimeters.

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

Finishing the floor

After installation, professional craftsmen recommend "walking" over the surface with a grinding machine with an abrasive nozzle from 80 to 120 units, in order to eliminate the slightest difference between the sheets. After that, the flooring is cleaned of dust and sawdust, and the seams are filled with a sealant or elastic wood filler.

It is undesirable to use polyurethane foam for seams, as it begins to sag and crumble over time.

A plywood floor can be installed even without extensive experience, sophisticated equipment or construction 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 that needs to be performed 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 is FREE and non-binding.

Leveling the wooden floor with plywood sheets in order to prepare the base for subsequent finishing with decorative flooring: carpet, linoleum, parquet, laminate.

Wooden floors are the classics of housing construction. They are environmentally friendly, wear-resistant, durable. But nothing lasts forever, and one day the need to renew the floor ripens. Outdated due to wear and tear or irrelevant appearance (the owners wanted to decorate the interior with new decorative flooring - laminate, linoleum, etc.), the wooden floor needs adjustment. After all, modern coatings need a perfectly flat surface. Plywood is a simple and inexpensive solution for this task.

So what you need to know and how to attach plywood to wood floors to turn creaky floorboards and unsightly surfaces into home decoration?

Preparing a worn wooden floor

Plywood is laid on a wooden floor after inspection and repair of the old coating:

• Dismantle the skirting boards.
• The decayed fragments of the floor are replaced with new ones.
• Squeaking and sagging floorboards are strengthened by screwing them to the beams.
• Places with damaged paintwork are treated with an antifungal compound (primer).
• Hang the plane with a level to identify drops and irregularities.

If the differences are significant, then equalization is indispensable. Most often, plywood flooring is used for this on a wooden floor - this material is most popular due to the availability, cost and convenience of working with it.

Minor irregularities and protrusions (2 - 4 mm) can be eliminated with a plane and / or a sander - in this case, the decorative coating can be laid directly on the wooden floor.

What plywood is used for the floor

Plywood is produced in various thicknesses, quality of grinding and processing. Therefore, an inexperienced builder is always faced with the question: what kind of plywood to lay on a wooden floor so that it is a reliable basis for a decorative coating.

• The plywood brand is not an easy choice for the DIYer. Usually the choice is made between FS and FSF brands. FC - plywood, in which the veneer sheets are glued together with a less toxic glue than the FSF brand (read: "Which plywood is better for the floor - choose the brand and grade of material"). However, the quality characteristics of FC are weaker: it is not too moisture resistant. Therefore, if environmental friendliness and safety are a priority (floors in the children's room, bedroom), then it is better to buy FC. For rooms with high humidity and traffic (an entrance hall of an apartment, a country house), the FSF is chosen.

Note: there are grades of plywood that combine strength, moisture resistance and safety (for example, FB), but due to the high cost (2 - 3 times compared to FK), an ordinary user rarely considers this option.

• The quality of the material also matters: the higher the grade of plywood, the better, smoother the surface, which means that the decorative coating will lie better and last longer. For leveling the floors, plywood of the 1st and 2nd grade is used.
• Plywood can be sanded on both sides (Ш2), on one side (Ш1), not sanded (NSH). For alignment, take Sh1.
• Material thickness. Experts believe that for floor work, this material should be at least 8 mm thick, and preferably more (in more detail: "What thickness of plywood is suitable for the floor"). How thick the plywood to lay on the wooden floor is regulated by a simple rule: the thicker the better. At a minimum, the plywood should not be thinner than the finish flooring.

Sometimes plywood is used as a sub-floor, laying the sheets directly on the logs. In this case, the thickness is needed from 2 cm.

Do you need preparation for plywood

Covering the floor with plywood onto the wood floor begins after the plywood sheets have been prepared. They need to be brought into the room where the installation is planned and left for 2 - 3 days. Wood has the ability to change its dimensions from humidity, temperature, so it is necessary that these parameters for the material and the environment coincide.

Experts advise to wet the edges of plywood sheets with water at room temperature if the room in which the work is being carried out is not regularly heated.

It is also advisable to treat the sheets with an antifungal and fireproof primer.

Attention: do not work with plywood in a room with high humidity: if condensation accumulates on a piece of film left in the room for a day, then it is recommended to dry the room using available means (heating devices, turning on the heating).

Measure seven times: cutting and fitting sheets

Sheets of the same shape are cut. Experts recommend 0.6 by 0.6m, but 1 to 1m or 1 to 0.5m is possible - it all depends on the thickness of the plywood and the convenience of work. After cutting, the sheets are tried on: they are laid on the floor, observing the "wandering" method - the transverse joints should not coincide, the look of the laid sheets resembles brickwork (read: "How to put plywood on the floor - laying rules"). Care should be taken to maintain a damping distance during installation: a gap of 2 - 3 cm from the wall, 0.5 - 1 cm between the sheets. If the fitting was successful, the sheets are numbered so that the final fastening of the plywood to the wooden floor goes smoothly, without frantic searches for the desired sheet. It is useful in addition to draw a numbered stacking plan. In conclusion, you should make a marking with a pencil or chalk on the floor in order to know where to arrange lags.

Note: the cut plywood is inspected for defects formed during sawing, delaminated or deformed ends of the sheets will affect the quality of the coating, it is better to replace them.

Plywood base tools

Before starting work, it is worth checking the availability of the necessary set of tools:

• Electric jigsaw;
• Drill with a set of drills;
• Screwdriver;
• Level;
• Roulette;
• Self-tapping screws;
• Dowel.

After installing the plywood base, you will need to prepare it for decorative flooring: for thin coatings (linoleum, carpet), you will need to carefully polish the surface. To do this, it is better to purchase a grinder or use a special drill attachment. You can use fine-grain emery paper if the floor area is small.

Plywood leveling technology

Before laying plywood on a wooden floor, choose the execution technology, the choice depends on the magnitude of the differences and unevenness of the wooden floor. Three alignment methods are used:

1. Leveling by laying sheets directly on the wooden floor. It is used if the irregularities are not more than 1 cm and are formed by the edges of the floorboards. The plane of the sheet, resting on the protruding edges, neutralizes the difference. This installation method often uses a plywood underlay on a wooden floor to cushion and improve thermal insulation.
2. Alignment with point supports (bosses). It is used as a budget option for floors with small differences. For the bosses, squares are used, cut from plywood, laminate, boards.
3. The lathing device for leveling the floors is used with horizontal differences of 1 - 8 cm. The strip support is made from beams or cut plywood strips, this method is the most expensive, but also the most reliable.

For any type of base, the rule applies: the thinner the plywood, the closer the anchor points should be.

The procedure for leveling using lag

Before starting the leveling, determine the level of the highest point of the floor. From this point, they begin to lay the logs - parallel bars. Lay the logs, adhering to the marks made during the initial layout of the plywood fragments. It is necessary that they are located at the interface of the sheets.

• Logs are stacked alternately, which are attached to the wooden floor with the help of special glue and self-tapping screws. Each beam is checked with a level in all directions, if necessary, placing bosses under it and filling in irregularities with plywood trimmings. Pieces of trim should be additionally greased with glue to increase the reliability of the base. There is a special adhesive for plywood on wood floors that does not require additional fixing. But more often craftsmen use proven methods: they lubricate the right places with available glue (Bustilat, Liquid nails, Moment), and then fix them with self-tapping screws.
• Then the crate is mounted - transverse bars located at a distance equal to the width of the prepared sheets and in accordance with the initial marks. It is necessary to carefully observe the markings so that the sheets, during the subsequent installation of plywood, do not, as they say, "hang in the air", but are attached to the crate and form a reliable plywood floor in a wooden house or apartment.
• To improve heat and sound insulation, the space of the lathing can be filled with the appropriate material, having previously got rid of construction debris.
• Plywood sheets are fastened according to the scheme, referring to the number labels. So that the caps of the screws do not protrude above the plane, they are recessed. For this, a recess is drilled at the attachment point, equal to the diameter of the screw head.

After the installation is completed, it remains only to prepare the plywood floor in accordance with the type of topcoat. For thin coatings, all irregularities, cracks at the joints, recesses from recessed self-tapping screws are putty. For tougher coatings, a special sound-absorbing underlay may be required. In any case, it is advisable to varnish the plywood several times to extend its service life.

Rules to know

Before putting plywood on a wooden floor, it is worth checking and repairing all communications running under the floor so that later you do not have to open a new finished floor. It is worth knowing that:

• The length of the self-tapping screws used in the work should be three times the thickness of the plywood.
• The distance between the screws is no more than 20 cm.
• The sheets are screwed, retreating from the edge 2 cm.
• In the presence of thin plywood, it is used in 2 layers, placing the sheets so that the seams of the upper and lower layers do not coincide.
• When constructing a plywood base using the point method, the bosses are placed at a distance of 20 - 25 cm.

Photos of beautiful modern coatings do not leave anyone indifferent, and an insufficiently even floor will no longer be an obstacle. Using these guidelines, any man who knows how to hold a tool will learn how to lay plywood on a wooden floor and can do it with his own hands.

polspec.com

People planning major repairs in an apartment or private house always ask themselves the question of leveling the floor. This procedure is really necessary, because in order to make the base strong and perfectly flat, you cannot do without it. In addition, many options for finishing the floor are also very demanding on the installation conditions. Floors are often leveled using materials such as OSB boards and plywood. Both types of material are in constant controversy. So, plywood or OSB - which is better for the floor? In this article we will try to answer this question.

To the content

Finding out the difference

Which material is better - plywood or OSB, because each of them has certain properties and has strict requirements for the laying process. Yes, they are very similar in many respects, the purposes of their use are also the same, but, nevertheless, each has its own pros and cons, which limit the use of a particular type of material in a particular situation.

Both OSB boards and plywood are used to create a perfectly flat subfloor, which is covered from above with a finishing material. Much here depends on the conditions, because the flooring can be arranged both on logs and on top of a concrete screed or old wooden floors.

Important! The installation of any of these materials using a lag should be done by means of rather thick elements, in turn, the lag bars should have a thickness of at least 4 cm. They are attached to self-tapping screws, and not to glue.

So, in order to decide which material to use, you need to figure out which one is better and which one is worse. To do this, you should take a closer look at these varieties, which are used for rough finishing.

To the content

What is plywood?

To decide for ourselves what is better to lay on the floor - plywood or OSB, let's study each option carefully, and start, perhaps, with plywood. She is well known to all. These are sheets made of wood veneer, glued with a special glue and pressed. The result is a solid and strong enough plate.

Features of plywood production:

• Veneer is glued, as a rule, in three layers, therefore, the thickness, reliability, strength of the material and the possibility of its use depend on their number.
• All layers are laid in such a way that in each of them the wood fibers are located perpendicular to the previous layers. It is due to this that plywood turns out to be so strong and resilient.

Important! Plywood is often used for finishing floors or creating various partitions. Even if it is made on the basis of synthetic fibers, it does not pose any danger to human health.

Elements are glued using synthetic glue or natural resins, which increase the environmental friendliness and safety of the material. The finished sheet has an absolutely smooth surface without knots and bumps, on one side it is perfectly sanded. Low-end products can still have roughness and knots, so they are used for rough work.

Important! Plywood is often used to create formwork at all stages of construction, furniture is made from it, floors are leveled with it, and screens and partitions are equipped.

Kinds

The plywood classification is as follows:

1. First grade. This is the highest quality and most expensive type of plywood. It is distinguished by its excellent appearance and durability. This material does not have any defects. It is the best option for creating floors, but the high price tag prevents many from using it. Simply put, this is an elite option.
2. Second grade. High quality plywood with a minimum of defects. The only thing that can scare her away is minor cracks, but they can be easily repaired even on your own. This material lends itself well to grinding and does not need additional special processing.
3. Third grade. Such plywood must definitely be further processed. It has defects, but there are not so many of them. Most often these are small knots or roughness that can be easily identified by touch. This is the best option for creating a subfloor, since its strength characteristics are quite high, and it costs less than other types of plywood.
4. Fourth grade. This is the cheapest type of material, the sheets have many defects, even small holes are often found. It arises due to the fact that low-quality raw materials are used in production. As a rule, at the factory it is not even polished or processed in any way. Therefore, it is better not to use it for arranging floors.

Of course, it is better to take plywood of the first grade (class) for finishing, since other options are usually used in cases where a finishing coating is provided. If possible, do not purchase the fourth grade - such a floor will not last long.

Important! Plywood can withstand 78% moisture for only 12 hours, but 68% for a long time. Untreated material is capable of withstanding a moisture content of no more than 60%.

To the content

What is an OSB plate?

We continue to find out which is more suitable for the floor - OSB or plywood. Now let's take a closer look at what an OSB plate is. This version of the boards appeared later than plywood, in fact, it was developed in order to replace it in those days when it was not easy to get plywood. Its name is translated as oriented strand board.

Features of the production of the material:

• Wood chips are used for the manufacture of OSB boards, which are combined into one structure due to resins and high pressure.
• At the same time, the chips are located outside, they are oriented along the slab, and those that are inside lie across the product.
• The shavings used to create the slabs must have specific dimensions: length - no more than 1.8 cm, width - from 5 mm to 4 cm.
• The finished products are capable of withstanding loads up to 100 kg / m3.

Important! If the technology for creating the plates was exactly followed, then they will turn out to be completely safe for humans. From the point of view of ecology, OSB boards are better than plywood, fiberboard and MDF.

Considering the above, you can immediately answer one more question: chipboard or OSB - which is better on the floor? Naturally, the second option is more preferable.

Types of OSB boards:

• First type. Such plates are more afraid of water than others, due to the fact that they are not able to fully resist the effects of moisture due to the low level of density. In addition, they are among the least durable.

Important! They are mainly used for packaging or making furniture. It is not recommended to equip floors with them.

• Second type. It is a durable material with low moisture resistance. Therefore, floors from such slabs are made only in rooms with the lowest humidity levels.
• Third type. This option is characterized by high strength and moisture resistance, which means it is the best option for laying the floor in rooms with high or moderate humidity levels.
• Fourth type. Such plates are not afraid of anything, they do not lose their performance even when used in the most extreme conditions.

OSB boards are also divided into three types, depending on specific characteristics. They can be:

• Lacquered.
• Laminated.
• Grooved.

Important! Yes, outwardly, OSB does not look as beautiful as plywood, because of the chips that are visible on the surface, which is why it is not used for finishing. But this material is ideal as a substrate.

As a material for leveling, plywood has the following advantages:

• Looks prettier.
• Does not deform.
• It dries up after getting wet and quickly returns to its former shape.
• Due to the special structure, through cracks do not appear on the product.
• Has a flat surface.
• The material is easy to process.
• For a long time it does not lose its characteristics.

OSB slabs are appreciated in construction for the following advantages:

• The material is relatively inexpensive.
• It can have different dimensions.
• Lasting.
• Resistant to moisture.
• Does not delaminate.

Disadvantages of plywood and OSB boards

We must not forget that these materials, like others, have some disadvantages. For example:

• It is undesirable to pour plywood with water, because, even though it quickly takes on its original form, it can begin to rot inside.
• When cutting, OSB boards emit too much dust and formaldehyde in minimal amounts.

And now let's summarize all of the above in order to clearly answer the question of which is better for flooring - OSB or plywood. We can say for sure that OSB reacts more strongly to water, faster plywood becomes unusable, especially when it comes to wet rooms. In such rooms, it is better to use plywood sheets. In terms of thermal conductivity, they are almost the same, but given the strength indicator, it is worth noting that plywood is better here. The choice is yours.

serviceyard.net

Plywood or OSB - which is better for the floor? - Encyclopedia of floor construction and renovation

Insulation of floors during repairs is a guarantee that the house will be cozy and warm, and on the surface of the floor covering it will be possible to move even barefoot without discomfort. And it is especially important to insulate the floor in Russia, since the climatic conditions here leave much to be desired in most of the regions. You can insulate the base under your feet with materials of various characteristics - this is isolon, and mineral wool so often used in construction. But can polystyrene be used for floor insulation? It turns out that you can, and this is one of the best insulation options.

What is polystyrene, its features

Polyfoam is actually familiar to every person. And the scope of this material is quite extensive. But few people know what foam is made of and what it is in general from a physical and chemical point of view.

So, polystyrene is light blocks of various sizes, consisting of foamed, but pressed together granules of such a substance as polystyrene. During the production of the material, the granules of this substance are treated with steam, the resulting particles go through a drying stage, after which they are glued and pressed into a single block. And at the same time, 97% of the foam is ordinary air. During the drying process, the foam acquires the very sound and heat insulation qualities that are familiar to us. Foam production is regulated by GOST 15588-66.

GOST 15588-86. Expanded polystyrene plates. Technical conditions. Download file (click on the link to open the PDF file in a new window).

GOST 15588-86

Comparison table of characteristics of foam and EPS

Comparative diagram of thermal conductivity of foam

Polyfoam is characterized by low thermal conductivity, which allows it to retain heat for a long time, thereby reducing heat loss in the house. Such indicators can be achieved precisely due to the porous structure of the material.

Polyfoam is not afraid of moisture due to a special production technology, when the granules of raw materials are processed with moisture-saturated steam, it is resistant to the appearance of colonies of harmful microorganisms on it, the growth of mold. It does not develop fungus, which in terms of health safety makes it one of the best insulation for walls and floors. Also, the material has a long service life and low weight, which is why they like to use it in construction. The material is easy to use, since, if necessary, it can be easily cut into the required dimensions of the elements, and you can drag the blocks on your own, without involving the help of third-party people.

On a note! To ensure the proper level of thermal insulation of the floor, it is enough to buy very thin blocks of polystyrene - 10 cm of material thickness is enough to cope with this task.

Polyfoam is an inexpensive material, somewhat tough and durable, does not need to arrange plywood structures for flooring, does not require special skills or knowledge from the master. It is ideal for coatings such as lamellas or parquet due to its sound insulation characteristics.

The main drawback of the material from the point of view of construction is its exactingness to the evenness of the base on which it will fit. If this condition is not observed, then the foam will break and crumble, as a result of which it will lose its properties, albeit partially.

On a note! Styrofoam is often confused with expanded polystyrene, which is used for packaging various fragile products. In fact, these are slightly different materials, although they have a lot of similarities. Packaging expanded polystyrene is fragile, and its thermal insulation characteristics are much lower than that of expanded polystyrene.

Table. Technical specifications.

Disadvantages of Styrofoam

Polyfoam is a far from ideal material, it also has its own drawbacks, which you need to know about in order to make your own conclusion - whether or not to buy such a material for floor insulation. The main ones are as follows.

1. Low strength indicators. The material is easily damaged or broken. But at the same time it is easy to cut.
2. The material is afraid of the effects of varnish or paint - it is destroyed because of them.
3. It is not breathable, although full of air in and of itself.
4. If mice or rats start in the house, then they can greatly spoil this type of insulation. Therefore, it is best to cover the foam blocks with plaster.
5. This is not an environmentally friendly material, and if set on fire, it releases a huge amount of toxic fumes into the air. But the foam itself is absolutely safe for humans.
6. The frame still needs to be created for foam, but in the case of this material, it can be made not as powerful as when using the same mineral wool.

Thermal insulation of wooden floors

Wooden floors are quite common both in apartments and in private houses. They are environmentally friendly, easy to set up and have good strength characteristics. However, on the lower floors, the relatively low thermal conductivity of wood is simply not enough to provide the proper level of heat, which means that the floors still need to be insulated. And here foam plastic will just be an excellent option.

As far as we know, a wooden floor is a whole structure, which assumes the presence of an air gap between the plank covering and the ceiling. And it is precisely in this space that blocks of foam plastic are required to be laid. Even a novice builder or a person who is far from the construction site, but decided to repair it himself or simply insulate the base, can do this work.

In any case, the use of foam requires careful preparation of the substrate. That is, it must be cleaned, leveled, and all gaps must be repaired. After that, the waterproofing coating is laid, on which the foam is then laid. But the installation of a lag from a wooden bar is preliminarily made.

On a note! Any material suitable for these purposes can be used as waterproofing, even ordinary plastic wrap.

Styrofoam blocks must be laid tightly, without gaps, and the joints between them can be foamed to reduce the number of cold bridges. Further, it is recommended to close the foam with another layer of waterproofing.

Advice! For laying insulation in a private house, it is better to buy polystyrene with a thickness of at least 10 cm. Moreover, the higher the humidity in the room, the thicker the insulation coating is used.

Insulation of a concrete base

The concrete floor is distinguished by high indicators of reliability, it is, as a rule, very even and durable, it is not afraid of serious loads. However, it cools down quickly, does not keep warm, and it passes the cold easily. That is why concrete floors are necessarily insulated. And here, too, foam comes to the rescue. However, depending on whether there is a basement under the concrete floor or not, the insulation technology will also differ.

With a basement

This section is relevant for owners of private houses or those who have apartments on the ground floors. Concrete floors in these cases are quite cold, and even a good floor covering will not save you from discomfort. Here it is recommended to fix the insulation precisely from the basement side, then the concrete slab itself, that is, the floor, will be in the air layer and it will be better to keep heat, and the cold will not penetrate into the house.

It is best to use styrofoam with a thickness of 5-10 cm, as is the case with wooden floors. If the concrete slab is uneven, then in any case it is important to prepare it for the installation of foam sheets. All cracks on it, if any, are sealed with polyurethane foam.

You can fix the foam on concrete using dowels 12-14 cm long. You need to work slowly, drilling holes in the concrete with a puncher, marking the places for fastenings. Before fixing the material, a special adhesive should be applied to the surface of the concrete, suitable for the foam. The joints between the fixed sheets can be closed with polyurethane foam.

Important! Styrofoam burns well and is easily damaged. Therefore, after installation, it is in any case important to protect it with plaster or ceramic adhesive using a thin reinforcing mesh.

No basement

If there is no basement in the house, and the apartment is located above the first floor, then another technology of floor insulation with foam is used. In this case, the sheets are installed over the concrete surface. The old flooring is completely removed, all cracks in the base are repaired, the floor is leveled. Cracks are best repaired with a thick cement mortar. Only after that, the floor is waterproofed with special compounds or materials. The easiest way is to use bituminous mastic, but in some cases, roll material will also be convenient.

After that, a reinforcing mesh or ordinary masonry mesh is laid on the surface of the waterproofing. And only then they put sheets of foam plastic on it. But here you can use thin sheets about 2-3 cm thick. The main thing is to mount with a minimum of joints so that cold bridges do not form. It is best to fix the foam with special glue.

Further, after laying the foam, beacons are installed using a laser level. They can be fixed with the same assembly glue. Lighthouses are placed at a distance of no more than 1.4 m from each other, but at the same level. After that, a screed solution is poured over the foam - a regular concrete screed is made, and the foam will be sealed on both sides with concrete surfaces.

Advice! You can level the surface of the concrete screed using a self-leveling mixture.

Polyfoam in the floor structure on the ground

In private houses, in some cases, the first floor is not built above the basement, but directly along the ground. Here it is important to pay maximum attention to heat and waterproofing. It is best to lay not one, but two layers of thermal insulation material. The floor can be either above or below ground level. In any case, it is important to use the thickest foam possible when installing floors.

The base for such a floor must be carefully leveled and compacted. After that, it is important to make a so-called cushion of gravel or gravel and compact it, and then cover the surface with a waterproofing coating. The best option is roofing material. Next, the foam plates are stacked very tightly to each other. Moreover, the joints of all seams should not converge in one place - it is better to lay the sheets in a checkerboard pattern. All joints between individual sheets are foamed.

Advice! The most recent sheets should be taken a little over the required size in order to install them with some effort.

Further, further waterproofing works are carried out again. You can cover the foam with a polyethylene film, but thick and strong enough. Next, the screed is poured using conventional technology. The thickness of the screed layer should not be less than 4 cm.

An example of floor insulation with foam

Consider step by step the insulation of the floor in the house with foam. This is a fairly simple option, and any person can do such insulation.

Step 1. First of all, the rough base must be cleaned of debris and all irregularities must be removed. If necessary, the cracks are repaired and the protrusions are sanded. It is important to remember that polystyrene does not tolerate a crooked base. Next, a waterproofing layer is laid. In this case, roll material is used, which is laid in separate strips with overlap on each other. In this case, the individual strips are fixed to each other by heating with a blowtorch. The waterproofing should be installed on the walls by about 10-15 cm.

Step 2. Next, you need to install the joists for the floor. In this case, they are wooden beams, on which the floor will subsequently rest under your feet. Logs should only be used from dry wood. Fixing the lag on the base can be done using dowels. The step between the lags can be equal to the width of the foam sheet.

Step 3. After installing the lag, you should lay all the communications that will be inside the floor pie. This can be wiring, pipes, and so on. Laying should be done in accordance with the project of the house or renovation. As for the water supply system, especially in a private house on the ground floor, it is best to put it on a heat-insulating material.

Step 4. Next, foam must be laid on the surface of the waterproofing layer between the logs. It is laid consistently and tightly so that no gaps are formed. But if they appear, then it is best to cover them with polyurethane foam. The lags should be so high that they are about 5-10 mm above the level of the laid foam.

Step 5. Then you need to "sew up" the floor cake with plywood sheets, OSB sheets or an ordinary board. Everything, the floor is ready, you can equip the finishing flooring.

Video - Floor insulation with foam

Polyfoam is really convenient and practical, and most importantly - an inexpensive material that is great for insulating floors in the house, as well as in any structure. It is easy to work with it, and the material performs its functions properly. So the main thing is to work without violating the technology, and then after installing such a heater in the house it will be comfortable and cozy.

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Laying plywood on a wooden floor with your own hands

Often during the repair, dismantling the old wooden coating is impractical, but it is required to level the surface for further work. In this case, experts advise to simply lay the plywood sheets, thereby creating the necessary "platform".

Laying plywood on a wooden floor

Plywood: advantages and disadvantages of the material

Pressed sheets are excellent material for roughing and initial work. They are inexpensive, easy to transport, easy to install and good at eliminating small differences in floor level. Often it is on plywood that they prefer to lay linoleum, parquet board or laminate, since it has the following advantages:

• laying sheets significantly reduces the preparatory work time before installing the final finishing floor covering;
• prevents decay of the underside of floor coverings, due to good ventilation between the material and the concrete screed;
• plywood-lined floor prevents premature wear or deformation of linoleum or carpet, extending the life of the decorative coating;
• provides an even sub-floor;
• plywood sheets are light, hard, strong, resistant to stress and abrasion;
• plywood is flexible enough and does not break during installation;
• does not have a pungent odor;
• has good sound and heat insulation properties;
• due to the large size of the sheets, the number of joints is minimal;
• A well-executed factory sanding prevents the sheet and materials placed on it from slipping.

Popular types of plywood used for renovation

The sheets produced by the industry are classified according to various criteria:

• used wood;
• availability and method of impregnation;
• grade;
• number of layers;
• surface treatment;
• moisture resistance.

For renovation work, when the part of the structure made of plywood will be hidden from view, it is recommended to use moisture-resistant plywood of grade II or III. The sheet must be at least 10 mm thick, but the recommended value is 14-22 mm. Thinner will not cope with the load, and too thick is inconvenient to work.

The number of layers is of no fundamental importance. If possible, you should purchase sheets sanded on both sides.

48 hours before the start of work, the material must be brought into the room where it will be installed and laid horizontally. There are two ways to install plywood.

Method 1. Mounting on an old wooden floor

When laying plywood on a wooden floor, there are many options for fixing the sheets:

• on self-tapping screws;
• on glue;
• on liquid nails.

Among the adhesives, there are water-based glue, two-component composition, assembly glue and bustilate. However, it is preferable to mount on self-tapping screws.

Materials and tools

For the successful installation of plywood sheets, you will need the following tools and materials:

• plywood sheets;
• jigsaw;
• level;
• roulette;
• marker;
• self-tapping screws;
• screwdriver;
• substrate;
• construction vacuum cleaner or broom.

You may also need a sander, roller and primer, glue and sealant.

Preliminary preparation and priming of the floor

Installation of plywood on wooden floors is carried out only if the height difference when checking with a level is no more than 1 cm. In this case, you will also need a substrate compensating for unevenness and adhesive tape, which will need to glue the joints of the strips of material.

Inspect the condition of the floors. Strengthen creaking and loose floorboards, replace rotten and damp floorboards. Do not try to restore boards with traces of mold, damage, attacked by rodents. They must be removed, the room must be ventilated.

Sweep dust and dirt off the floors with a broom. If desired, go through the wood primer twice for better material adhesion. And dry the base for at least 16 hours.

Marking and cutting

Plywood sheets are sawn so that the number of joints is minimal, taking into account damping joints of 3-4 mm between the sheets and 8-10 mm between the plywood and the wall. This will help to avoid swelling of the sheets, since during operation, under the influence of the microclimate and fluctuations in temperature conditions, the workpiece will increase by several millimeters in area.

Cutting is done with a jigsaw, while the ends of the blanks are carefully inspected for delamination and sanded. On large areas, for ease of installation, plywood can be cut in 50x50 or 60x60 cm squares. This technique will help to more accurately level the surface and eliminate possible laying defects.

The sawn sheets are numbered, and similarly to their numbers, a schematic arrangement of the workpieces is drawn on the wooden base.

Laying plywood

The assembly of workpieces has several features.

At the end of the installation, you should check the quality of the coating, remembering that the ideal gap between the level and the plywood is 2 mm, the maximum is 4 mm.

Method 2. Installation of plywood on logs

A more complex and time-consuming method of laying plywood material on beacons is justified if the height difference is more than 1 cm.Lags can be installed on an old wooden floor only if you are sure that everything is in order under it

Preparatory stage

Old flooring needs to be cleared of dust and debris, paying sufficient attention to the gaps between the floorboards. The largest cracks can be filled with silicone sealant or assembly adhesive.

At this time, plywood should be prepared - the material needs to be sawed, markings should be made on a piece of paper and the squares should be numbered, taking into account that they will be laid out in a "brick".

Installation of logs and plywood sheets

Lags - guides that help level the floor surface. They are slats with a length of 1.5-2 m and a section of 40x15 mm, which are attached to wooden boards with dowels or self-tapping screws. The lags are set in such a way that their upper boundaries form a single plane, and the slats themselves form a crate.

The spaces between the guides must be filled with soundproofing insulation.

If necessary, cords and communication wires can be hidden in layers of insulation.

According to the drawing, the plywood squares should be installed. Fastening can be carried out with liquid nails or self-tapping screws, in the latter case, the screw heads must be properly drowned. The holes can be pre-marked and countersunk.

Final processing

At the end of the laying of materials, the joints of plywood sheets should be treated with fine-grained emery paper, this will smooth out all the irregularities and differences in adjacent sheets. After sanding, the entire surface must be covered with several coats of varnish.

1. If a laminate or parquet board will be mounted on top of plywood, then the thickness of the plywood should not be less than the topcoat.
2. Try not to allow cases where 4 plywood sheets touch at one point at once.
3. The pitch of the log should be 0.5 m from the side of the square.
4. Plywood cannot be used in rooms with high humidity, even if it is a moisture resistant grade of material.
5. If non-moisture-resistant plywood is used in the work, then a prerequisite for the next stage of work will be the laying of a layer of waterproofing.
6. The length of the self-tapping screw should be at least 2.5-3 times the thickness of the plywood.
7. When laying plywood on logs, after the mother-in-law is embedded between the boards, the base can be primed and a layer of heat and waterproofing can be put, and only then the guides can be mounted.

It is important to remember that defective plywood sheets cannot be used in work, even if they are supposed to be further coated with decorative materials.

Video - Laying plywood on a wooden floor

pol-spec.ru

which is better, advantages and disadvantages, photos and videos

The construction of the sub-floor is a necessary step when laying various floor coverings such as linoleum or parquet. Materials made of veneer or shavings glued together with special compounds are used as the basis for the floor.

Any construction begins with the choice of material, so you have to decide: which is better - chipboard or plywood on the floor. We will help you make a decision by talking about the advantages and disadvantages of different materials, as well as their installation.

Composition and structure

The main material used in the manufacture of chipboard and plywood is wood, however, plywood is a more natural material, because less glue is used to glue it together.

The main differences between plywood and chipboard:

• Plywood is a multi-layer material that consists of veneer sheets glued together. Inexpensive tree species are used as veneer: spruce, birch and pine. The number of veneer layers determines the thickness of the plywood sheet.
• Chipboard (chipboard) is made from woodworking waste: shavings, sawdust, etc. All of this waste is mixed with a lot of glue and pressed into sheets.

Properties and benefits

Plywood or chipboard on the floor - which is better? To answer this question, you need to carefully understand what you want to get from the material, because plywood has a set of some properties, and chipboard - others.

Comparative characteristics of materials:

• For the construction of the subfloor, the aesthetics of the material used is not important, however, it is worth noting that plywood can be used even for finishing flooring, treating it with varnish.
• Particleboard and plywood are materials with poor moisture resistance. Plywood of the FK brand is able to withstand the impact of a small amount of water, while chipboard does not at all resist the action of water, drying out and finally deforming.
• Chipboard has a more fragile structure: during operation, the material will begin to wear out quickly, crumbling under loads, when fastened, for example, self-tapping screws are worse adhered to glued shavings.
• Despite all the disadvantages, chipboard is often used as a material for a subfloor, because these boards have better sound and thermal insulation than plywood, and also have greater bending strength.
• Another advantage of chipboard is its price. When comparing plywood and chipboard of the same quality, you will notice that the price of particle board is significantly lower than the price of plywood.

Both materials should be used only in dry heated rooms, because when exposed to moisture, the sheets will rot, as well as spread mold and mildew, which will make them unusable, and also spoil the finishing flooring. It is recommended to treat the material with special antiseptics even in dry rooms (in more detail: "How to treat plywood on the floor - should it be impregnated").

If the humidity of the floor in the house is high enough, then you can use special plates - OSB, also laying a plastic film for additional waterproofing.

Do not forget that for the manufacture of boards with a high degree of moisture resistance, more toxic adhesives are used, which can negatively affect your well-being during use.

Both materials are easy to install. You will be able to do-it-yourself sub-floor assembly using the tools that can be found in any home. Chipboard is a heavier material than plywood, but it is easier to cut (read also: "Which plywood is better for the floor - choose the brand and grade of material").

Also, do not forget that when sawing chipboard, a lot of toxic dust is generated in the air, so you should use a respirator to avoid allergic reactions.

Having considered all the properties of both materials, it is difficult to choose one, because each has its own pros and cons, therefore, to the question: "Plywood or chipboard on the floor - which is better?" everyone has to answer for himself.

Subfloor device made of sheet materials

The sub-floor can be laid on old surfaces such as planks, as well as on concrete screeds or joists.

Chipboard or plywood is easily attached to the floor from old boards using self-tapping screws and glue, but it is worth talking in more detail about fasteners on the screed and logs (read: "Self-laying chipboard on the floor - options for arranging the floor").

Concrete screed flooring

A concrete screed is the most reliable base, but its construction takes a lot of time and effort. Installation of such a screed begins with a markup: draw horizontal lines along the walls of your room along the building level. These lines are the upper edge of the future concrete screed.

The next stage is the selection and laying of the bars. The bars are used to organize the inner frame, so they must be thinner than the screed itself in order for the cement mortar to cover them. The bars are laid in a grid, the cells in which are equal to 1 square meter.

Concrete pouring is the final stage of concrete screed construction. For filling, a cement-sand mortar is used in proportions of 1: 3. Fill the cells with concrete and smooth it evenly, then let the concrete dry.

If the quality of the screed obtained is important to you, then make sure that it does not crack. To do this, keep the moisture level high, for example, by covering the concrete with plastic for 8-10 days.

It is worthwhile to start laying the subfloor only after the concrete floor is completely dry, otherwise the material used will become unusable.

There are two ways to check the moisture content of the floor:

1. Use an expensive moisture meter that can be rented.
2. Place polyethylene on the concrete area and press down along the perimeter, then leave overnight. If the concrete is not dry enough, then in the morning you will find condensation on the surface of the film, and if it is not there, then you can safely proceed with the installation of the subfloor.

Laying plywood or chipboard sheets begins with adjusting them. Cut the sheets so that there is a distance of 2 cm between the wall and the outermost slabs, and also keep a gap between the slabs of 2-3 mm. See also: "How to Attach Plywood to a Concrete Floor - Laying Options".

It is worth laying the slabs according to the brickwork rule in order to prevent premature wear of the material. After that, number them so you don't get confused later.

Apply glue to the concrete and lay the slabs, then additionally secure them with dowels. You can see the finished result in the photo.

Installation of a subfloor on logs

Installing sheet material on logs is an easier way, but it is in no way inferior to the previous one. The main advantage of this method is the space between the lag cells, in which you can put noise and heat insulating material, as well as arrange engineering communications in them.

Laying the subfloor on logs requires a more durable material, so the thickness of plywood and chipboard should be at least 20 mm, provided that the distance between the logs does not exceed 40 cm (read: "How to make floors from chipboard on logs with your own hands").

Installation process:

1. Draw up a scheme for laying the lags so that the joint of the sheets occurs in their middle. As a result, you should get a grid with cells of 30-50 cm.
2. Align the longitudinal logs horizontally using shims or a plane. Leave a distance of 2-3 cm from the walls.
3. Attach the transverse logs to the longitudinal ones with nails driven in at an angle. The result of the work done is a grid of bars, as in the photo.
4. Start laying sheets from the corner, stepping back 10-15 mm from the walls. Mark at the edges of the sheet the middle of the intermediate logs and connect them in order to later screw the self-tapping screws along this line into the center of the log. Secure the plywood sheet with long self-tapping screws that go deep into the log. Observe a step of 10-15 cm.
5. Attach the rest of the sheets in the same way, keeping a distance of 2-3 mm between them.

Important amendments:

• Do not forget to lay the sheets according to the brickwork rule.
• When using grooved sheets, there is no need to leave a gap between the slabs. Cover the joints of the plates with glue and seal the sheets together with a mallet.

Plywood sheets should be additionally treated with antiseptics and drying oil.

polspec.com

What is the best plywood for the floor

Plywood is a material that is great for creating and renovating a variety of floor coverings. Its use opens up significant prospects for builders in arranging not only the final floor, but also the fasteners of the subfloor. In this article we will try to figure out what kind of plywood you need to buy for the floor and what should you focus on when buying this material?

The use of plywood sheets for flooring can be attributed to several factors. Plywood for the floor is inexpensive, looks great in the interior, makes it possible to level the floor with the least expenditure of time and resources, which greatly facilitates the repair procedure. Plywood will fit perfectly both for finishing work indoors and for installing the base for finishing materials, as well as for repair work or eliminating small flaws.

Most often, the difference in floor level in old apartments fluctuates up to 10 cm, therefore, the simplest option of laying the floor covering "in the forehead" cannot be realized. And in the event that you are going to lay laminate or parquet tiles in your home, the site should be perfectly flat. But owners of a crooked floor should not be upset, because plywood is an excellent raw material for leveling the surface. You can do this procedure yourself.

The main advantages of plywood include:

• naturalness of the material, because plywood, unlike OSB and fiberboard, is created from natural raw materials, and not from production waste
• humidity level ranges from 12 to 15%
• plywood takes the brunt of variable loads. As a result, the screed remains intact, and microcracks form in the wood. However, they have absolutely nothing to do with the quality of the floor.
• due to the fact that it is made of wood, it creates good contact with the finishing materials. Consequently, the period of operation of the latter increases
• using this material, you can get a floor covering that meets the specified indicators with less time and money
• no special preparation is needed to lay the plywood on the floor; this work can be carried out in several stages
• it acts as a certain kind of insulation material, because it reduces heat loss through the base
• plywood sheets can be used to create both a rough and a final floor, it all depends on the type and nature of processing.

However, this material is not suitable for rooms with significant temperature differences (for example, for summer cottages or seasonal buildings), as well as with high levels of humidity.

What plywood to lay on the floor

When buying plywood in a hardware store, you need to pay attention to the following parameters:

• brand. For interior work, it is preferable to use the material of the FC brand. Its level of moisture resistance fully meets the conditions of use in residential buildings.
• emission class. Only class E-1 is suitable for creating a floor.
• grade of material. In the process of creating a subfloor, it is permissible to use raw materials of 3 and 4 grades, and for the final one - 1 or 2 grades
• humidity level. High quality material with a moisture content of 12-15%
• number of layers. Plywood veneer is used with a thickness of 1.7 to 1.9 mm. It is the number of layers that determines the thickness of the sheet. Strength increases with the number of layers. During the creation of the subfloor, material with a thickness of 12-18 mm is used, and the final one - 10-12 mm
• sheet dimensions. Floor plywood can be formatted and large format. Dimensions are set by GOST. Size matters for shipping and storage
• company - manufacturer. Foreign and Russian companies sell raw materials of decent quality. But material from China often receives negative reviews and often does not meet the stated parameters.

By the type of adhesive used, plywood sheets are of the following types:

• FC - has an average resistance to moisture
• FSF - characterized by increased moisture resistance
• FBA is a non-waterproof material, but at the same time it is highly environmentally friendly
• FB is a material used in water.

It is quite easy to apply the rough floor. This work takes little time and does not require any special equipment. It can be done in several ways:

• the material is laid directly on the concrete base using a special adhesive. In this case, it is imperative to leave a 3mm tolerance between the sheets so that destruction does not occur during operation. Because when the temperature in the room fluctuates, natural raw materials expand or contract. This flooring option is preferable in rooms with no difference in height.
• in the event that you are going to create an adjustable floor, then the installation of the lag is not needed. Height differences are eliminated using fasteners under the plywood sheets
• the most tedious procedure can be called the creation of warm floors; in this work, plywood is laid on logs.

In addition to the subfloor from plywood, experts even create a palace parquet. However, in this case, it is necessary to use only grade 1 material, the front surface of which is carefully sanded. To obtain a unique pattern, the plywood must be stained, and the parquet must be carefully sanded and varnished several times.

In the event that the topcoat is linoleum, experts do not recommend laying plywood on a plank base.

Masters advise two most suitable methods:

• in the case of a satisfactory condition of the old wooden floor without serious flaws and squeaks, it can be smoothed with a sander. Plywood fits perfectly on a wooden floor. Before this procedure, you need to sink the heads of the nails so as not to damage the apparatus. On the base obtained in this way, you can immediately lay linoleum. For this work, FC material of grades 3/3, 3/4, 4/4 is suitable.
• if the old floor is in very poor condition with rotten areas or dents. In this case, you need to dismantle the old base, and lay 18 mm plywood on the joists. Anything can be mounted on such a base, even artistic parquet. But do not forget to leave a compensation gap of 3-5 mm between the sheets. And the gaps between the lags must be filled with expanded clay for moisture and sound insulation.

Many people ask themselves: what kind of plywood to use for the floor? Craftsmen prefer to use FSF sheets due to their high moisture resistance. However, it is better not to buy this material, because the layers are glued with an adhesive containing phenol-formaldehyde resins, which can release phenol. This volatile compound will definitely penetrate the room and will not bring any health benefits.

FC floor plywood is often produced in a square shape, so the material needs to be sawed very often. For this purpose, a jigsaw connected to an industrial vacuum cleaner is most suitable. This way you can get excellent results. When using a fine-toothed hacksaw, the result may not be very beautiful.

Floor plywood is subject to heavy stress. If the installation of plywood is carried out on a continuous plank covering, the sheets will not sag. However, when mounted on logs, the support area is minimal, and the thickness of the plywood must be increased. Experts recommend the FC grade with a thickness of 15, 18 or 20 mm. Birch plywood is best suited because it is more durable than softwood. The gaps between the joists should not exceed 400 mm. And the thickness of the lags themselves should be more than 50 mm. The bars must be chosen whole and strong: material with defects must be immediately put aside and not used.

We hope that the material presented in this article will help you decide which plywood is best to lay on the floor.

wood-prom.ru

which to use, to lay, which variety to choose, how to put on photos and videos

Plywood is a fairly durable, and at the same time, natural material. The unique mechanical properties of plywood are given due to a special manufacturing technology, which implies gluing an odd number of thin layers of wood veneer with perpendicular alternation of fibers.

Due to its low cost and high fracture strength, plywood has become widely used in construction. This interest is due to the fact that for a long time in the past, plywood was, so to speak, the only finishing material that could be easily obtained. For this reason, many varieties and types of plywood have appeared on the market.

Types of plywood

Plywood is divided into types, based on the scope of its application: construction, furniture, construction, industrial, packaging.

The type of plywood is determined based on the glue used during production:

• FC is a water-repellent type of plywood. Its sheets are glued together with urea glue;
• FSF - plywood with enhanced water-repellent properties. In this case, the layers are glued with phenol-formaldehyde glue;
• FBA - ordinary plywood, sheets of which are glued with albuminocasein glue. Such plywood is afraid of moisture, but it is chosen because of its harmlessness to humans;
• FB is a plywood designed for use in extremely humid conditions, even in water. Such qualities are acquired by the material due to its impregnation with bakelite varnish.

Only the most famous types of plywood are listed above. There are additional classifications, depending on the thickness of the wood used, the quality of the surface.

Pros and cons of laying plywood on the floor

Benefits and which plywood is best for the floor:

• Plywood is a very environmentally friendly material made from natural raw materials, which cannot be said about fiberboard and OSB, which are production waste.
• The moisture content of plywood does not exceed 12-15%.
• Due to its strength, plywood has excellent shock absorption properties. In the event of a strong impact, the screed will remain intact, and the plywood will only receive microcracks. It won't make the floor worse.
• Plywood has excellent contact with various floor coverings, as it is made of wood.
• A floor made of plywood will meet the required quality characteristics, while it does not require a lot of time and resources to make it, and you do not need to have special skills. It can be performed step by step.
• In addition, plywood serves as a kind of insulation, protecting the room from the cold given off by the concrete base.
• Plywood is an ideal solution when leveling a floor with large differences, since the screed in this case will be more expensive, and the base will significantly increase in mass.
• Many grades of this material allow it to be used as a rough and finish floor.

The negative qualities of plywood include the impossibility of using it in rooms with strong temperature fluctuations (summer cottages or houses with temporary residence) and excessive humidity (baths, saunas, bathtubs and swimming pools).

Choosing plywood for laying on the floor

In order to understand which plywood is best for the floor, you need to remember two important factors:

• What type of floor will be used will significantly clarify the situation, since it is impossible to choose plywood for the floor without taking into account this nuance, otherwise you can end up with a low-quality floor.
• In addition, the type of room itself affects which plywood to use for the floor. For example, if the room is living and there will be children in it, then it is recommended to use only FC plywood. It does not contain formaldehyde, therefore it is harmless. The main thing is that the humidity level is observed in the room. If plywood is to be laid in a production facility with normal ventilation installed, then the best answer to which plywood to lay on the floor will be FSF grade 1 emission class. This class indicates the inclusion of formaldehyde not more than 100 mg per 1 kg of plywood board.

Plywood classifications

When deciding which plywood is better to lay on the floor, you need to navigate in the following parameters:

• Plywood brand. As described earlier, FK plywood is the best choice for living rooms with moderate humidity.
• Plywood class. That is, its emission, only E-1 class can be used for the floor.
• Plywood grade. There are 4 grades, however, different sides of plywood sheets may differ in grade. For example, you can see the markings: 1/1, 1/2, 2/2 and others. For a rough base, grades 3 and 4 are suitable. For a fine base, 1 and 2.
• Humidity. High-quality plywood should have a moisture level of 12-15%.
• The number of layers. The used veneer can have a thickness of 1.7-1.9 mm. Plywood with more layers is stronger. This parameter determines where it will be used. For the rough finish, you will need plywood 12-18 mm thick, and for the finishing coat, 10-12 mm. For the installation of plywood in production, it is recommended to use plywood more than 25 mm thick (read: "What thickness of plywood is suitable for the floor").
• Dimensions of plywood boards. There are small-format, large-format and format sheets. The dimensions of the plywood boards are more important for transportation than for installation. Large sheets are more difficult to work with, but you can always adjust them to fit the smaller size you want. The main thing is, even before installation, do not forget to number the cut sheets so as not to confuse them during installation. Experts recommend offset stacking.
• Plywood manufacturer. Samples of plywood of our own production, as well as those from European manufacturers, are approximately the same in quality, which cannot be said about Chinese plywood, which is often criticized by buyers due to inconsistencies with the specified characteristics.

Installation of plywood on the floor

Installation as a sub-floor

Using plywood as one of the types of rough flooring is the simplest and most affordable solution.

• Plywood is laid on a concrete floor with sheets 10-12 mm thick, which are glued directly to the base. It must be prepared and smooth. During the installation process, it is imperative to leave 3-4 mm gaps between the sheets, as well as the space between the sheets and the wall. This will enable the plywood to expand easily due to changes in climatic conditions.

In addition, large differences in height can be leveled with plywood, the main thing is to arm yourself with special fasteners.

• If you plan to equip adjustable floors, then logs are not required, you only need special fasteners installed under the plywood.
• Laying of plywood sheets on logs or floor beams is possible. You will need plates of at least 12 mm and a finished frame base. Such a floor will require the most time for its implementation; there is a need for it when you need to insulate the floor or raise it to the required height. The use of adjustable lags allows you to eliminate the difference in floor heights.

Plywood as a leveling layer

Very often there are situations when the old floor has already lost its previous appearance, but can still be used without problems. You can safely lay a floor covering on such a floor.

But if you do not want it to deteriorate ahead of time, it is worth installing an additional intermediate plywood leveling layer.

Installation of plywood on a wooden floor is carried out using self-tapping screws. The process is fairly easy and quick.

We have now figured out which plywood to choose for the floor in this case.

However, in order for it to serve for a long time, you need to adhere to a number of rules during installation:

• sheets must be fastened securely, do not forget about the gaps;
• the caps of the self-tapping screws should sit under the sweat;
• all irregularities should be eliminated with a grinder;
• all cracks and depressions must be filled;
• in addition, you need to cover the substrate.

The only thing is that laying plywood is impractical if a wooden floor is laid on top. Massive boards of such a floor can be laid both on logs and on a concrete floor.

Plywood for finishing

Experienced specialists can make a real palace parquet out of plywood. Usually only the highest quality parquet was used for these purposes.

Currently, to achieve this result, you need to take a first grade material with a polished front surface. To get a beautiful pattern, the plywood is sanded after installation, opened with wood stain and parquet varnish.

Processing, operation and storage of plywood

If plywood accidentally gets wet during transportation, looks just damp and has not had time to swell, it should be dried as soon as possible. To do this, leave it in a ventilated room, spreading the sheets close to each other.

It should be remembered that FC plywood and other types of it cannot be dried by direct exposure to heat - this can cause its destruction, it is likely to swell, or, even worse, catch fire. The best drying process is exposure to natural dry air.

If plywood is stored in an insufficiently dry place before starting work, it is better to check all sheets before starting work. Good plywood that can be installed should be free of peeling and staining, which could indicate fungus spreading over the surface.

If you want your floor to last for many years, you need to protect the sheets while they are being laid.

When handling plywood, you need to remember some important conditions.

The need for acclimatization.

You cannot stack the material you just bought, it must be kept in the conditions of the exploited climate. This period depends on the previous storage conditions: position, temperature and humidity.

If the difference between the past and current temperatures, as well as humidity is minimal, and at the same time the material was stored in a dry room and on a flat surface, then it will be enough to leave the material for a day. If the temperature difference is 5-8 ° C, and the humidity is 10%, then it costs 3-5 days to withstand the plywood.

If the difference is greater than these values, and the sheets have slightly changed their regular even shape, then the sheets will have to withstand more than a week. At the same time, to align the plywood on the stack, you will need to place something heavy, and during installation, you will need to use more self-tapping screws than usual.

Dampness of the room

Rapid changes in humidity can drastically damage the wood material, in this case plywood. The humidity level in the room should be constant, and at the same time not exceed 70%, and short-term increases - no more than 80%. Plywood should not be placed on a damp floor.

To control the moisture content of the tree, you can use a special device. To check the concrete floor, you need to take a plastic wrap and lay it down, slightly lifting the ventral part. If condensation forms, additional drying of the room will be required.

Installation temperature

Ideally, when plywood is laid at 20-30 ° C. Such conditions are most favorable for wood materials.

Material quality

It is very important to achieve the best operating conditions that the material is well processed. It is important to cover the sheets with an antibacterial primer, which will protect the plywood not only from microorganisms, but also from various fungi.

If the plywood is additionally impregnated with a putty with the addition of PVA glue, this will improve its moisture-repellent properties. Opening it with acrylic varnish will enhance the strength characteristics of the outer layer.

In this article, you familiarized yourself with which grade of plywood is best for the floor, what types of it are, how best to store and install it. Correctly selected plywood will not only simplify the installation process, but also enable the future flooring to last as long as possible. And most importantly, all work can be done without the help of specialists.