The scope of this sheet material is quite extensive. When doing work on your own (construction or repair), plywood is often used in arranging the floor - both for leveling it for the finish coat, and for mounting it on logs of light flooring for further painting or applying varnish. Regardless of the goal pursued by the home master, the technology is identical in both cases.
And given the exact geometry of the plywood sheets, the simplicity of their cutting and low weight, all activities for installing the floor from plywood along the logs at each stage can be done by hand, without resorting to the services of various advisers and assistants.
By itself, the process of arranging a plywood floor will not cause any difficulties even for a non-specialist. The main thing in this work is competent preparation for it. The quality and durability of the coating directly depends on the choice of appropriate materials. For those who are really interested in the final result, the author strongly recommends that you carefully study the information below, and only then master the nuances of installing plywood along the logs.
Sheet stacking scheme
You should start with this. In order to draw a plan of a particular room on a sheet, taking into account all the features of its configuration, you do not need to be a specialist. The main thing is to maintain the scale. After that, measurements of all the linear parameters of the room are made and put on the diagram. It turns out a drawing that will be needed to calculate the required volume of purchase of the required materials.
What is the feature? Plywood sheets have the correct geometry, and go on sale. Mostly for domestic use, samples of 244 x 122 or 152.5 x 152.5 (cm) are purchased - this is the standard format. There are more overall products, and when finishing large areas, it is much more convenient. But the question arises - how to transport it? For example, with a sheet length of 3.6 m (these are also sold).
After drawing up the plan of the room, it remains only to apply a “grid” on it, the cells of which are projections of each sheet. The task is simple - to draw up a diagram of their laying in such a way as to engage in cutting as little as possible. For those who first come across the issue of arranging floors on plywood logs, it is worth explaining what such careful planning gives.
- The amount of waste is reduced, therefore, construction (repair) is partially cheaper. A zealous owner will appreciate this.
- When it comes to doing this or that technological operation with your own hands, it is understood that the home master uses a household tool. Does every home have a jigsaw? So, you have to cut plywood with what is at hand. For example, a hacksaw. And this is both time and low quality of the cut.
What to consider?
When drawing up a plywood laying scheme, it is necessary to arrange all the sheets so as to cover the maximum possible area with them, and it is with whole samples. Naturally, there will be separate sections for which you will have to cut (in size) fragments. But in this case, you can also purchase the so-called substandard. It is in every building / materials store and is sold at bargain prices. As an option - buy sheets of plywood of smaller sizes (there are also such).
Such careful preparation will significantly reduce costs. By the way, this applies not only to plywood (the number of sheets and their sizes), but also to logs. They are also characterized by different lengths, so you have to decide on them.
Choice of plywood
By variety
One of the tasks of do-it-yourself work is to achieve maximum savings. From the same point of view, you need to approach the acquisition of consumables. In terms of quality / cost per sheet for arranging floors, the best are. Both of them are moisture resistant, are sold in a large assortment, have identical linear dimensions and sample thickness. What is the difference?
- FSF costs 1.5 times cheaper than FC.
- In the manufacturing process of both plywood, adhesives are used to hold the veneer layers together. But if the preparation for FC does not contain toxic components, then they are present in the glue for PSF (formaldehyde). That is why the last modification is recommended mainly for external work, since when the ambient temperature rises, harmful substances begin to be released from such plywood.
How to proceed? If the floor is arranged along the lags in a residential area, it is unambiguous to focus on the FC sheets. For installation in unheated utility rooms (sheds, outbuildings), cheaper plywood with the FSF marking is also quite suitable.
Thickness
The purchase of plywood for this parameter is complicated by the fact that the following points must be taken into account. Firstly, the interval between the lags, which is selected depending on the characteristics of the arrangement of the floor. For example, how and with what it is supposed to be additionally insulated. Secondly, it is possible to increase the strength of the flooring not only by increasing the thickness of the sheets or reducing the distance between the lags, but also by laying plywood not in 1, but in 2 layers.
- For a single-layer installation scheme, it is worth purchasing sheets with a thickness (mm) in the range of 15 - 18 (depending on the expected load on the floor). Reducing this value will not ensure the reliability of the coating, increasing it will complicate the work with sheets (first of all, cutting them) and increase the weight of the entire structure to be mounted (and this is an additional load on the floor).
- If it is planned to lay plywood in two levels, then samples with a thickness of about 8 - 10 mm can be purchased.
By grade of plywood
As a rule, when arranging floors along logs, cheaper sheet material is purchased. After all, all its flaws are reliably hidden by the finishing. The main thing is that the samples do not have significant defects in the form of chips or emerging cracks.
In some cases, the owner leaves the flooring as it is, covering the plywood only with varnish. With a similar organization of the floor, the purchase of sheets with a grade below 2/4 is impractical. What is the feature of this product? GOST allows the presence of defects on its surface, but only on one side. When arranging the floor along the logs, such plywood (2/4) is the best choice.
According to processing
It is appropriate to note such a characteristic of the sheet material. In order to optimize costs, you should pay attention to plywood, the abbreviation of which contains the designation NSh (unsanded) or NSh1 (with one-sided sanding). Accordingly, what is better to buy depends on how it is planned to finish the subfloor further. If you only paint (apply varnish) - then NSh1. In other cases, cheaper sheets with the designation NSh are sufficient.
Log selection
By material
There are only two possible options - metal or wood. If we consider from the point of view of ease of installation, weight, correct geometry and a number of other parameters, then the conclusion is unambiguous - it is better to purchase metal logs for arranging the floor. But such a judgment does not take into account all the nuances of operation.
In any room, the microclimate changes, sometimes quite dramatically. First of all, this refers to temperature. Its differences cause deformation of materials. To make the design as stable as possible, when combining several different types of elements, they are selected according to expansion coefficients; they should be as equal as possible.
What is a plywood joist floor? Sheets are glued and pressed layers of wood veneer. Therefore, it is better to choose a wooden base on which they are supposed to be fixed. That is, a beam or a thick board mounted on an edge. No matter how convenient metal is to work with, it is unlikely that warping of the floor will be avoided with such lags. If not immediately, then in a couple of years it will definitely manifest itself.
By type of tree
The specifics of the room (dry or wet) does not yet give a complete understanding of the conditions in which the wood will be. Logs are mounted on the ceiling. What is under it - a heated room on the ground floor, a basement or something else? Options may vary. But the probability of rotting, deformation of the material in any case cannot be ruled out.
What is recommended? Larch is the best solution. This coniferous wood is not only resistant to dampness, but unlike other similar species, it does not tar so intensively when the temperature rises, and when wet (in the future) it only gains strength. No wonder it is her experienced craftsmen who use it when laying the lower crown of the log house. In addition, the price of lumber is quite acceptable.
Geometry
It's short here. All joists must be absolutely straight. Even the slightest distortion is unacceptable. Otherwise, not only their alignment when laying on the base will be complicated. Even slight mismatches in the upper cuts in height will lead to the fact that the plywood floor will turn out to be uneven. It is extremely difficult to fix such defects of it, and even in several places, with your own hands.
The optimal cross-section of the beam for the log (mm) is 100 x 50.
According to wood moisture
You need to purchase for the log only lumber dried in production (with an indicator not higher than 12%). It costs more than natural moisture products, but it is here that the savings are not justified. It is unlikely that it will be possible to achieve proper drying of wood on your own - this is a complex process that requires time, a suitable place, and competent organization.
Choice of fasteners
- The plywood floor is good because it is easy to repair by replacing the sheets. Therefore, as fasteners - only self-tapping screws (for wood).
- Since any floor is necessarily subjected to wet cleaning, the hardware must be made of stainless metal. There are enough galvanized self-tapping screws on sale.
- Leg length. It is selected depending on the thickness of the plywood sheets and should exceed it by about 2.5 times - this is a general rule for work related to fixing materials on the base.
Plywood floor on logs - work procedure
Foundation preparation
The main goal is to eliminate defects in the floor and ensure its high-quality waterproofing. If the floor is arranged along the logs in a new house, then the task is greatly simplified. It is enough just to lay a p / e film (thickened) on the base with the expectation that its edges wrap onto the walls, and fix the sections with construction tape. The excess above the floor - the height of the lag + the thickness of the plywood sheets + another 2 - 3 cm. The protruding film will subsequently be covered with a plinth.
If the leveling of the subfloor is carried out in an already inhabited room, then there are two possible options.
- Complete dismantling of the entire structure and work from scratch.
- Removing the flooring (with the lag remaining) and waterproofing the floor with penetrating compounds.
The feasibility of a particular solution is determined by the state of the lag and the base on which the installation is carried out.
Installation of the supporting frame
Many questions arise regarding the interval between lags. Partially about what needs to be taken into account (plywood thickness, room area, installation scheme) has already been said. But the main criterion is the dimensions of the sheets. They are laid on logs so that the cuts coincide with the longitudinal axis of the guide.
Therefore, you should focus on the distance between the lags within half a meter. If it is required in some areas, then additional logs are mounted. Actually, the drawing is also drawn up in order to determine their optimal placement in the room. As a result, the supporting structure should look something like this.
What to consider:
- A wooden “shoe” is placed under each rail (from pieces of MDF, OSV, fiberboard, trimming a thin board). It is easy to fix it on the ceiling. What is the advantage of such a solution? Firstly, there will be good air circulation under the plywood floor, which will partially prevent the formation of mold. Secondly, with this method of installation, it is easier to align the upper sections of the log.
- Work begins at opposite walls. Along each, with an indent of 3 ± 0.5 cm, one log is laid. They are aligned in a horizontal plane, and later serve as a guide for mounting the rest.
- To achieve maximum alignment of the lag with your own hands, it is advisable to make a special device. The device is simple - a long rail, in the middle part of which a level (building) is fixed. Even better is to buy (or rent) a level. Then there won't be any error.
Floor insulation
From the point of view of "easier, faster, cheaper" - pour expanded clay between the lags or lay mineral wool mats. The work is so simple that it is not worth considering this issue in more detail.
At the same stage, engineering communications are laid (if necessary) - TV lines, Internet, and so on.
Fixing plywood sheets
Work feature:
- First, a “fitting” layout of the sheets is done. After they are aligned and adjusted, the installation points of the fasteners are marked.
- Each sheet is additionally processed (edges are cut at an angle) and holes for self-tapping screws are drilled.
- Countersink. It is mandatory, since the fastener caps must be recessed into plywood after screwing it in.
- Placement of sheets. They are mounted one at a time, starting from any of the corners of the room. After alignment with the lags, it is advisable to make “channels” in the beam with a thinner drill. Then the leg of the self-tapping screw will enter the wood quite easily. If the installation is carried out with a screwdriver, then this can be neglected. The main thing is that the fasteners "went" strictly vertically, without distortions.
The figure shows an approximate scheme of their laying.
What to consider:
- The placement of self-tapping screws depends on the dimensions of the plywood. Mandatory fastening - around the perimeter of the sample. But the additional fixation is determined by its size. For large-format sheets - according to the scheme crosswise, for small fragments it is enough only in the center.
- To reduce the so-called “shat” of sheets, it is worth putting strips of roofing material under them (on the logs).
- Plywood is laid so that when it is joined, the bevels form a groove. It is easily filled with sealant, completely closing the resulting gap. This increases the hydro, heat and sound insulation of the floor.
- To mask the hats of fasteners, special compounds are also used. They are on sale in various colors. If the plywood is varnished, then it is not difficult to match it to the tone.
If plywood is laid in two layers, then its fastening is done as follows.
The final stage is the cleaning of all joints. As a rule, it is enough to go over the seams with sandpaper to remove excess dried sealant. And then - according to the plan: coating with varnish or paint, finishing with other materials. The main thing is that the plywood floor is completely ready.
Plywood is one of the most versatile materials invented by mankind. Plywood is also widely used in construction: in terms of ease of working with it, strength, cheapness and environmental friendliness, plywood, perhaps, has no equal. Plywood is especially widely used in laying and repairing floors. But the high functionality of plywood also determines the variety of methods of working with it, so laying plywood on the floor with your own hands requires explanation for different cases of practice.
Chipboard or plywood?
Plywood is not the cheapest material for flooring and wall cladding. Chipboard is even cheaper. But let's leave alone for now phenol-formaldehyde resins - volatile carcinogens, on the basis of which chipboard is made.
Let's do the following experiment: put two pipe cuts on the floor and lay a sheet of plywood 12 mm thick on them. Let's get on it, let's go. What happened? Nothing. Bent over and straightened up. What about chipboard? Most likely, it cracked at a greater thickness. And it will definitely crack if you jump on it.
You can do two more experiments: hold plywood and chipboard trimmings in water and see how soon they swell and become limp. It is not necessary to knock on the edge with a hammer: everyone knows that chipboard is fragile. Therefore, the question: “chipboard or plywood?” definitely decided in favor of plywood.
What is plywood
There are many varieties of plywood. In construction, plywood of the following grades is most often used:
- FC - moisture resistant plywood on urea resin, non-volatile and non-toxic. It has strength and elasticity comparable to BS aviation plywood.
- NSh - unpolished on casein glue. The cheapest, about 170 rubles / sq.m with a thickness of 12 mm. Before gluing parquet or other hard flooring onto it, it requires sanding.
- Ш1 - the main material going to the subfloor. Sanded on one side. The glue base is also casein.
- Ш2 - polished on both sides, on casein. For lightly loaded parts in dry rooms and with a comfortable temperature, it can be used as a substitute for FC.
What is contraindicated for plywood
Nothing is perfect, and plywood is made from a hygroscopic material - wood. Therefore, plywood cannot be used in damp rooms: long-term air humidity should not exceed 68%; short-term within 12 hours - 78%. When laying raw plywood, air humidity up to 60% is acceptable.
The specified values are valid in a comfortable temperature range of 18-27 degrees Celsius. Outside these limits, the sensitivity of plywood, except for FC, to humidity increases: at 16 and 35 degrees and a humidity of 85%, plywood begins to delaminate after two months. Therefore, ordinary plywood for floors and walls should not be used in the kitchen, balcony, closet, hallway and bathroom.
How to improve plywood
Moisture resistance of plywood can be increased by impregnation with putty based on polyvinyl acetate (PVA); it looks like very liquid PVA glue and is cheap. Impregnate first on one side until spots appear on the opposite side, then on the other twice. Dry in a horizontal position. It will take a long time to dry - at least 3 days at room temperature. After drying, the sheets are treated with any antiseptic fungicide for wood.
The strength of the surface layer can be increased with acrylic varnish. It is applied in two layers; the second - after the complete drying of the first. If plywood for decorative purposes needs to be stained, paint before varnishing.
Acclimatization of plywood
Before describing how to lay plywood on the floor, it should be said about its acclimatization in the room. Plywood, like any wood-based material, requires acclimatization at the place of use. The term of acclimatization depends on the difference in temperature and humidity: if the conditions in the warehouse or in the store are the same as in the apartment, a day is enough; with a temperature difference of 2 to 8 degrees - three days; with more - a week. During acclimatization, the plywood is kept stacked in a horizontal position.
Subfloor Moisture Check
Before laying plywood on the floor, the base surface, and not only concrete, you need to check for moisture evaporation. To do this, 1 sq.m of the base surface is covered with a single square piece of polyethylene film, pressing it along the edges with slats with weights and raising the center a little. Further depends on the time of appearance of condensate under the film:
- The bubble fogged up from the inside during the day - the room is unsuitable for covering the floor with plywood.
- Small drops appeared within 3 days - the base concrete floor must be covered with glassine or plastic film, put a construction mounting grid on it and make a screed. Wooden floor - disassemble; with such evaporation of moisture, the boards from the underside and the old logs are probably touched by rot. An option for 7-10 years is to lay plywood with an improved home method (see above) moisture resistance.
- Condensation did not fall out on the 5th day: you can lay plywood in any way.
plywood base
Leveling the floor with plywood is a widespread building technique. It is used both for laying new floors and for express repairs of existing ones. For different combinations of base floors and top decorative coating, different plywood laying technologies are used.
Concrete
Laying plywood on a concrete floor is possible both directly on the screed and on logs. The first method is used if the base floor is sufficiently even, and the finish coating is somewhat plastic; for example - under linoleum or cork floor. Marmoleum can be laid directly on the screed without a subfloor.
Important: remember that after the concrete has set, it must be dried for at least 40 days at room temperature.
On a flat dry screed
The room is thoroughly swept and vacuumed. The floor is treated with bituminous varnish or parquet mastic, diluted five times with solvent or kerosene (primerization). When working, windows are wide open, they work in a respirator-petal, and in the apartment completely, having unscrewed the plugs or turned off the machine on the floor panel, they remove the power supply: there is no need to explain what a spark is in air saturated with vapors of an organic solvent.
Plywood 8-18 mm is pre-cut into squares a quarter of a standard sheet (1250x1250 mm) or stripes. Lay apart, i.e. with a shift: there should not be four seams converging at one point. Sheets are cut with a jigsaw or a manual circular saw - this can be done in the next room an hour after priming. When cutting, it must be borne in mind that a gap of 20-30 mm should remain along the perimeter of the room.
Then the sheets of plywood are laid out on the floor, “dry”, adjusted and numbered without fastening. How to fix plywood to the base floor in this case? Under linoleum or cork, you can simply use glue such as bustilat or parquet mastic, without mounting slots - you get a floating subfloor. The ends of the sheets must also be glued.
Under ordinary oak or parquet similar in properties, plywood, along with gluing, is fixed with self-tapping screws 4-5x60 mm in dowels. In this case, sheets / strips must be laid out with mounting slots of 2-3 mm; For this, it is convenient to use halves of toothpicks:
Note: as a screwdriver insert for a drill, it is convenient to use the insert of a combination screwdriver (see figure above).
On concrete on logs
Under a laminate, inlaid parquet or parquet made of fine wood, plywood is laid on a concrete base on. The same is done if the stability of the temperature and humidity conditions in the room is in doubt. The device of the draft plywood floor on the logs is clear from the figure, we will give only the necessary explanations:
- Boards for lags take unplaned 100 mm ("weaving").
- Boards for lags can withstand at least a week in the room where they will be used, after which they are culled: those that are warped by an arc are put on the bosses, and those that have been driven by a screw are completely rejected.
- Plywood is taken by FK or improved independently, with a thickness of at least 12 mm; better - 18-20.
- The preparation of the base floor is done in the same way as in the previous case.
- Lathing of logs is made in increments of 300-600 mm so that all edges of the plywood sheets fall on the logs.
- The sections of the crate are filled with polyurethane foam or other hydro- and heat-insulating material, but not with mineral wool - microscopic needles will inevitably appear in the air from it, irritating the respiratory organs.
- Plywood sheets are laid with a mounting gap of 2-3 mm and with a gap around the perimeter of the room of 20-30 mm.
- Attach plywood to the joists with liquid nails glue and fix with nails; fastening with self-tapping screws in this case does not noticeably improve the quality of the subfloor, but it is more expensive.
Note: recently, tongue-and-groove plywood 12-20 mm thick has appeared on sale especially for subfloors. It is produced in the form of sheets from 300x300 mm and strips from 300x600 mm. For a floor made of valuable parquet, this is the preferred option: the cost of a subfloor in this case will still be an insignificant fraction of the total cost of materials, and the likelihood of moisture vapor leaking from under the bottom is reduced by an order of magnitude.
Repair of wooden floors with plywood
Plywood is an excellent material for repairing cracked wood floors that are cracked and creaky. In this case, plywood is laid on a wooden floor in whole sheets from the door so that the most walked surface is solid. Scraps are allowed along the edge and into places under furniture. The plinth is removed as carefully as possible and then it is put back.
Plywood is taken from 12 mm thick. Installation is done with the usual gap of 20-30 mm around the perimeter, but without mounting gaps between the sheets. Sheets are laid on bustilate, liquid nails or any other mounting adhesive; the ends are also glued.
Such a floor made of “self-improved” plywood, painted with any floor enamel, lasts 20 years or more in the bedroom. But it is impossible to repair damp, swollen floors with plywood, with traces of rot and mold, and in rooms with biting biting on the walls is impossible. It is necessary to remove the old floor, look for and eliminate the source of moisture, and only then lay a new one.
Warm floor on plywood
Under plywood, they are laid on a concrete screed on a mounting grid with waterproofing on the base floor. There is one caveat here: the edges of the waterproofing film must be brought under the plinth. If they are muffled with a screed, then the evaporation from heating can concentrate in one place and cause delamination from moisture.
When installing a subfloor under a warm one on the logs, such a problem does not arise, but it makes no sense to complicate and increase the cost of work: a warm floor dries the room well. So it's easier to leave a kind of vent around the perimeter for water vapor.
Plywood innovations
Plywood flooring is a branch of construction engineering that seems to be far from over. In the age of composites and nanotechnology, the good old plywood does not retreat and finds new uses for itself.
Adjustable floors
These floors are used as a base for wood inlays and other fine, exclusive work. Plywood flooring - double, made of high quality plywood. In the sheets of the lower layer there are threaded sockets for bolts. The bolts are shaped: above the thread there is a flat flare in the form of a press washer, and above it is a neck 3/4 of the thickness of the sheet for a hexagon or with a cross slot.
The top sheet with holes for the necks of the bolts is placed on the bolts screwed into the bottom sheet, and adjusted with an open-end wrench or a screwdriver. When using bakelized plywood, the accuracy of the overall surface is quite machine-building.
Plywood parquet
But plywood parquet is an invention of craftsmen. In it, the forgotten art of plywood sawing was revived at a new level. The technology of plywood parquet is simple and accessible to anyone.
If you lay plywood on a concrete screed, then during operation the plywood sheets will take the brunt of the blow. Microcracks form on the wood, but they do not affect the quality of the floor.
The wood building material from which the subfloor is made is in good contact with any exterior finish. This has a positive effect on the condition of the floor over the years. The surface remains smooth, without cracks, bends.
Another advantage of using plywood is the ease of installation. This material is easy to cut into pieces and quickly laid. One person will be able to carry out all the work with minimal experience behind him, and at hand the most common construction tools.
Plywood has low thermal conductivity, which reduces heat loss in the room. And if you take sheets of the highest grade and fine grinding, then you can use them for the final finish.
Where not to apply
Despite all the advantages, plywood sheets are not recommended for use in rooms with high humidity. This is their minus. Plywood is not laid in baths, pools, showers, bathrooms. Of course, there are moisture-resistant laminated varieties, but their price is high, so not everyone wants to use them on a large area.
It is not advised to cover the floor with plywood in rooms with a strong temperature difference, for example, in unheated summer cottages. Strong heat after freezing can cause the sheets to warp.
What kind of plywood to lay
Before laying plywood on the floor, you need to familiarize yourself with its characteristics:
- the brand for the dwelling must be FC. This is the safest option, although its moisture resistance is not very high. Laminated products are also used, but they are higher in cost;
- class for security purposes choose E1 or E0.5;
- inexpensive 3rd and 4th grades are suitable for the subfloor; for a finishing one, you need to take a higher grade. Often there is a designation of varieties 2/2, 2/3, 1/2 and the like. So indicate the grade of veneer from different sides;
- the moisture content of the sheets should be no more than 15%, the lower it is, the better;
- plywood used for the subfloor must have a thickness of at least 12 mm, for finishing, a value of 10 mm is allowed. Can be applied in two layers. In workshops, workshops, public areas with high traffic, the thickness can reach 2.5 cm;
- for subfloors, unpolished plywood, designated NSh, is suitable. It can also be polished on one side - Ш1.
Laminated plywood with a mesh texture is used mainly for flooring in transport. It is suitable for finishing on terraces, in country houses, outbuildings.
The dimensions of the sheets are chosen in accordance with their own needs, they are not of fundamental importance for laying. It should be borne in mind that the larger the sheet, the greater its mass. The process of transportation and manipulation during installation becomes more complicated. To avoid stress in the material under load, large sheets are sometimes cut. When sticking to a screed, it is convenient to work with squares of 75 x 75 or 60 x 60 cm. Elongated strips are suitable for logs. In large rooms, they may not be cut.
Domestic manufacturers offer good quality plywood, which is quite suitable for the floor. The same applies to Western European brands. As for Chinese goods, one must be careful when choosing, because there are products that do not meet the standards. For example, the declared thickness may be greater than the actual one.
Subfloor laying options
Plywood is easy to lay on a flat concrete screed in the apartment. Sheets 12 mm thick are glued to the surface, after checking its horizontalness. Height differences should be no more than 2 mm, otherwise it is necessary to fill for leveling and wait for it to dry completely.
Note! For any installation at the joints of the sheets, it is necessary to leave gaps of 2.5–3 mm, retreat from the walls by 1–1.5 cm. This will avoid deformation during temperature and humidity changes, there will be no squeaking, deflections.
Plywood sheets are laid with a slight offset so that there is no clear joining of the four corners. This installation increases the strength of the floor covering.
The most common mounting method is on wooden joists. He is able to replace the screed. The surface is perfectly smooth, it can be used for any finish. Legs can be adjustable. How to perform such an installation will be discussed below.
With a height difference on a wooden floor, fasteners in the form of studs or screws are used, which allows you to level the surface without using a log. This is an interesting installation method, in which fasteners (screws, self-tapping screws, studs) are drilled over the entire area at the same distance from each other. The height of their heads should be at the same level. You can check this with a laser or a regular level. It is necessary to screw the hardware evenly. Foam is squeezed out between the fasteners and a thick plywood sheet is laid on top.
Lag installation
If it is necessary to insulate the floor, level or raise it, then logs are used. Do-it-yourself installation of a plywood floor along the logs is more laborious.
It is recommended to take plywood with a thickness of 12 mm or more. You can use two layers of 9 mm sheets or take sheets of different thicknesses, but so that they are all the same in one layer. The top layer can be laid out from thinner sheets. The total thickness of the plywood coating can reach 25 mm. The second layer is laid so that the joints do not coincide with the first.
Bars with a section of 70 x 50 are used as a log. Bars and plywood sheets must be aged at room temperature for several days before they are mounted. Moreover, the plywood must be in a horizontal position so that there are no bends.
Logs are screwed with anchor bolts to a concrete base or strong screws to a tree (if, for example, laying goes on an old wooden floor). The first log goes at a distance of 30 cm from the wall, then the subsequent logs are laid in increments of 50 cm, strictly parallel to each other.
Note! For screwing plywood sheets to the logs, only high-quality self-tapping screws for yellow wood are used.
Self-tapping screws must be fully tightened and not break. Their length must be at least three times the thickness of the plywood sheet.
Of the tools used are a circular saw, a laser level, a meter and a screwdriver. It will be nice to impregnate all wood materials with fire protection.
The walls do not always go smoothly, so the first sheet must be leveled with a level and a square. Next, sheets are measured, cut with a circular saw and laid out on the surface. The layout should be with a run-up so that more than two corners meet at one point. And do not forget about the deformation gaps.
Self-tapping screws can be quickly screwed if countersunk holes are drilled in advance. It is convenient to use a screwdriver with a countersink. The distance between the screws is 20–30 cm. At the same time, there must be at least 8 fasteners on one sheet.
After the floor is laid, everything is fixed, the left joints are sealed with special mastic.
Leveling plywood sheets
In old houses, there are floors with worn wooden boards. If the wood is not rotten, then it should not be removed. It is enough to remove the old paint, remove debris, level the floor with plywood sheets from above. Such a multilayer flooring will be an excellent heat insulator. As a finish, you can use laminate, linoleum, parquet board.
Laying plywood on a wooden floor is carried out in the same way as on a screed, leaving expansion joints (gaps). Fix the sheets with self-tapping screws, twisting them so that the hat is recessed. Then they level everything with a grinder, cracks, putty grooves. If it is necessary to install a parquet board, then cover the substrate.
Plywood is not laid under a wooden floor from a board. Natural wood is quite massive, materials from it are laid directly on the logs.
Finished floor
There is controversy over whether plywood can be used for fine flooring. Many people say that such floors look unpresentable, but there are good examples of fine plywood flooring.
Note! If you want to lay out a finishing floor with plywood, then choose high grades with a polished front surface.
For decoration use square or rectangular panels. If you plan to lay out some special pattern, then first make a sketch. The most common layout option is staggered or herringbone. It is very similar to wooden parquet.
The base on which plywood boards will be laid must be perfectly even, regardless of whether it is a concrete screed or wood material. The surface is primed, which ensures good adhesion. Next, mark up on plywood sheets and cut out plates of the required size. Each plate is numbered, as in a sketch or diagram, in order to know exactly where to lay it. This is especially important for a complex pattern, but if all the plates are the same size and shape, then there is no need for numbering.
Advice! To make the joints look better, chamfer is removed from the ends of the plywood. You can also use T-shaped plastic inserts at the joints.
First, the plates are laid out on the floor, then finally glued. To give a shade, plywood is treated with stain and opened with several layers of matte varnish. You can use opaque paint to hide bumps and stains if they have formed after applying the stain. One of the design options is to seal the joints with putty, paint with enamel paint, which will protect against moisture and hide imperfections.
Plywood on wooden floors in the house allows you to level the base without dismantling the old wooden flooring. The substrate in this case prevents squeaking and other problems that may arise. The technology allows you to do the installation yourself without serious difficulties.
The choice of material for the production of work
Laying plywood on a wooden floor is a great solution. This do-it-yourself rough coating has the following advantages:
- low cost;
- ease of transportation;
- reduction of preparatory work time;
- good leveling of small floor defects and increase the service life of the floor covering;
- strength and wear resistance of the material;
- flexibility, which allows not to break and not crack during operation and installation;
- the minimum number of joints between sheets;
- installation is carried out without serious labor costs.
Before laying the material with your own hands, you need to choose it correctly. There are several classifications according to various criteria:
- by grade and type of raw materials used (wood);
- impregnation (its presence and method);
- grade;
- surface treatment method;
- number of layers;
- moisture resistance.
Laying plywood on a wooden floor in a house (rough coating) involves the following recommendations for choosing when doing do-it-yourself work:
- the flooring is made of sheets of the second or third grade, the use of the first is not justified from an economic point of view;
- in the house it is best to use moisture-resistant material, this is especially important when installation is carried out in wet areas (bathroom, bathroom, kitchen);
- flooring involves the use of sheets with a minimum thickness of 10 mm, but this is only suitable for small rooms with low traffic;
- laying technology in more critical premises suggests that the substrate under the finished floor will be made of a material with a thickness of 14-22 mm, such sheets have sufficient strength;
- it is recommended to choose materials sanded on both sides (if possible).
Preparatory work
Wood floor preparation Before laying plywood on a wooden floor in a house, the flooring and surface must be prepared. Do-it-yourself activities are as follows:
- the base for the installation of plywood must be cleaned of debris, dirt and treated with antiseptic compounds; when laying without a log, it will be necessary to perform priming;
- checking the condition of the floor, removing and replacing damaged elements;
- if there is time, it is recommended to arrange the sheets vertically and dry them for 2-3 weeks, while the temperature should be at room temperature or slightly higher;
- after drying, the sheets are treated with antiseptic compounds;
- further it is necessary to ventilate the material;
- if there is a need to increase strength, it is worth treating the plywood with acrylic varnish, the coating is made in several layers;
- when laying with your own hands, you need to bring the sheets into the room in two days and lay them out horizontally, this is done so that the material adapts to the temperature and humidity conditions of the room.
Methods of work
Installation in the house can be done in two ways:
- laying on an old wooden floor (suitable for a small height difference);
- installation on logs (with differences of 1 cm or more).
Leveling the old floor
Installation of plywood on wood flooring In this case, plywood can be fastened in three ways:
- glue;
- liquid Nails;
- self-tapping screws.
It is worth noting that the latter option provides the most reliable fastening of sheets than laying on glue. Adhesive compositions can be water-based, two-component, mounting glue or bustilat is also used.
Mounting on glue is carried out in the following order. After completing the preparatory work, the floors are checked by level. If the vertical difference is less than 1 cm, then the method described below can be used. To compensate for irregularities with their own hands, a plywood substrate is used, the joints of which are glued with adhesive tape.
Plywood layout options Next, you need a layout of sheets, which will allow you to most rationally cut the source material. The plywood is preliminarily laid out taking into account the seams for the expansion of the material under load and with temperature fluctuations (damper seams are 3-4 mm). Leave 8-10 mm between the wall and the subfloor.
After laying out the sheets, the elements are cut with an electric jigsaw to the desired size. If installation is required for a large room, squares with a side of 50-60 cm are used. All parts of the coating must be numbered in the order in which they must be laid later.
When fastening to self-tapping screws, holes are drilled in the sheets, which are then countersinked using a larger drill. When laying on glue, it would also be wise to make an additional mount. The holes are located at a distance of 2 cm from the edge of the part. The step between the fasteners is taken equal to 15-20 cm.
The production of works begins with such elements as niches, ledges, raised podiums.
It is necessary, when attaching to glue and in other ways, to place the elements of the subfloor with dressing. It is similar to brickwork, that is, each subsequent row is mounted with an offset relative to the previous one. The easiest way is to shift half the sheet. The minimum offset is 10 cm.
The glue is applied in an even layer 2-3 mm thick on the base. After laying the sheets, they are pressed down with a roller. In order to ensure greater reliability and prevent displacement when mounting on glue, self-tapping screws are used.
The procedure for laying plywood sheets After fixing, the sheets are ground with a special machine with a coarse emery nozzle.. The evenness of the rough coating is checked by the rule (with a rail at least 2 meters long). It is applied to the surface and the fit is checked. The gaps between the tool and the surface when laying on the adhesive should be no more than 2 mm.
Laying on lags
Laying plywood on joists This method is more laborious, but allows you to eliminate significant defects in the base. When cleaning and checking the old flooring, special attention is paid to the seams between the floorboards. If necessary, they are spilled with adhesive to prevent problems (creaking).
Cutting sheets for the floor along the lags is performed in the same way as in the previous case. First of all, you need to fix the logs - wooden boards with a section of 40 by 15 mm. Elements are laid on the old coating in one direction. The step is selected based on the size of the plywood sheets. It is necessary to make sure that the seam between the elements falls on a wooden lath.
Installation instructions for plywood sheets on logs When installing the floor on the logs, the boards are fixed on the wooden floor with self-tapping screws. Fastening sheets to the guides is done in the same way. Soundproofing material is laid along the lags (between them). Most often, a heater is used for this. If it is necessary to lay communications, then they are placed in a layer of thermal insulation.
It is most reliable to attach the sheets to the guides for self-tapping screws, but liquid nails can also be used. Holes for fasteners are pre-drilled in the same way as when laying without a lag (observing the same requirements). Next, the surface is processed in the manner described above (grinding).
With proper installation, you can not worry about the durability of the finish coating and the creaking of the floors. It does not really matter which method is chosen: by lags or without them. It is important to do the work in accordance with the technology.
We are coming to the end of our big topic of creating a high-quality, even and durable floor in an apartment. Today we are waiting for the last stage - laying plywood on the floor. After that, any floor covering can be mounted on plywood, and here your imagination is completely: linoleum, carpet, laminate, parquet board, block parquet.
Laying plywood on the floor
Laying plywood on the floor is carried out in several successive stages, which we will now discuss.
Cooking plywood
We lay the first sheet in the most even corner, as always leaving a temperature gap of 3-5 mm between the wall and plywood. Then we put the next sheet. While we do not fasten anything! At the end of the row, it is necessary to cut out an incomplete piece with an electric jigsaw (first we measure everything). In order for the joints to go in a checkerboard pattern, in the next row of plywood we lay a whole sheet opposite the cut one. Thus, we lay plywood over the entire floor area.
How to fix plywood?
We approach this process with the utmost care. Plywood should be one with the black floor. No gaps, otherwise everything will creak. Therefore, do not spare the screws, get ready to tighten their pieces of commercials in 2000 :).
Important!
Do not drive screws directly into plywood! Under each self-tapping screw, a hole with a diameter slightly smaller than the diameter of the self-tapping screw (countersink) should be drilled. Through this you will receive:
- Tightly drawn plywood to the boards.
- Perfectly flat plane. Plywood will not warp from a lot of self-tapping screws.
This is, of course, a rather laborious process. But if you want a flat floor, don't be lazy! Pick up a drill, screwdriver and go!
How to draw plywood?
It is possible in two ways.
- The first is the simplest, for lazy people. Approximately by eye, drill holes with the indicated pitch (10 × 15 cm). There is a big minus here - some self-tapping screws can get into the edge of the boards, or even they won’t hold between them at all!
- The second way is correct. While the plywood is lying on the floor, alternately lift each side of each piece and mark on the plywood the middle of each board lying under the plywood. Then, using a long ruler, we draw lines corresponding to the position of the boards under the plywood (with a step of 10 cm - our boards were just 10 cm wide). Next, we draw perpendicular lines with a step of 15 cm. We also make a number of self-tapping screws on the edges of the plywood.
Important!
Drilling is not done on lying plywood sheets in order to avoid drilling boards together with plywood. In order not to confuse the sequence of sheets, we mark each sheet, where and on which side it lay.
All plywood sheets should be primed. This will protect the plywood from possible moisture and increase the adhesion of parquet glue (if future parquet is supposed to be planted on glue). Prime the bottom of the plywood sheets before laying, the top - after the sheets are fastened with self-tapping screws.
We prepare a cork substrate for plywood
Plywood is ready. Now we clean the surface of the black floor - carefully sweep all the garbage. Then we roll out the prepared cork backing roll on the floor:
Cork underlay needed! It evens out all the micro-roughness of the boards and ensures a snug fit of plywood to them.
We put the cork neatly butt. And so that it does not move when laying plywood, we let a thin strip of PVA glue under the edges of the cork along the joints and near the walls. Then we press the edges of the cork (especially where they bulge) with the rest of the boards for 3-5 hours.
Attaching plywood to the floor
The cork is laid and the glue has dried. Now we lay the plywood. It's better to do it together and carefully.
Important!
If you hook the cork with a plywood corner, move it or tear it, everything is gone!
First, lay the first sheet of plywood in its place. When he already lies with the whole plane on the cork substrate, all the terrible things are over. The sheet can be gently moved, the cork will not move or tear, it is held by glue. Thus, we lay all the sheets of plywood according to the markings and fit them tightly together. If gaps of 1-2 mm remain, this will not damage the parquet.
We laid all the plywood, now we fix it with self-tapping screws. First we fix all the corners, then everything else in any order. The most important thing is to screw the self-tapping screw so that the cap is pressed into the plywood and is slightly below the plane of the sheet.
Important!
Avoid protruding hats. But do not immerse too deep - it can lead the sheets!
This is what plywood looks like:
Important!
Pay attention to the edges of the sheets - a line of self-tapping screws is required along the edge!
Boxes of self-tapping screws show how many were used. It took us about 2000 pieces for a room of 14 m².
We laid the plywood, now it remains to sweep it and cover it with soil.
This completes the laying of plywood on the floor:
Well, dear readers!
You have made a solid, high-quality basis for your future floor!