A wooden floor that has even slight unevenness causes significant problems when installing any floor covering. Old wooden floors that characterize houses, cottages, city apartments that have long term operation, most often require careful alignment. Leveling a wooden floor with plywood will help eliminate all unevenness and prepare the base for further installation of laminate, carpet, linoleum and other types of floor coverings. This method is quite simple and popular, allowing you to create a perfectly flat surface.
Using plywood to level a wooden floor is the best option for situations involving further installation of laminate flooring. In this case, use plywood with a thickness of at least 12 mm, but if the surface is fairly flat, then you can stop at a thickness of 8-10 mm.
Performance characteristics of plywood
Plywood has a number of advantages that position it favorably for leveling the floor in a wooden house:
Plywood has unique characteristics that make it a popular material for renovation work:
- Simple processing and installation technology;
- High quality grinding;
- No unpleasant or foreign odors;
- Excellent surface hardness;
- Light weight sheet of material;
- High strength under load;
- Excellent performance properties of moisture-resistant and water-resistant plywood.
The structure of plywood is characterized by a layered appearance. It consists of veneer, carefully pressed and glued together. The thickness of plywood is determined by the number of such layers, which give it resistance to stress and strength. Achieving such important characteristics of the material is possible thanks to the special placement of veneer layers, each subsequent row is located perpendicular to the fibers of the previous one.
It should be noted that the number of layers in any type of plywood is always odd. For example, twelve mm sheets have 9 layers of veneer. However, purchasing plywood for leveling a wooden floor requires taking into account not only the thickness of the material, but also a number of other characteristics, such as brand, grade, degree of surface treatment and emission class.
Plywood grades
Plywood is divided into grades depending on the degree of moisture resistance. There are four types of stamps:
- Plywood intended for industrial construction work– brands FB, FOF;
- Plywood intended for individual construction and repair work - grades FK, FSF.
Let's take a closer look at the grades of material intended for individual construction.
The FC brand is characterized by average moisture resistance. Veneer gluing is carried out using fairly safe adhesives based on urea resins. This brand of plywood is used for interior decoration and furniture production.
The FSF brand is characterized by increased moisture resistance, but its use at home is undesirable. During its production, veneer sheets are glued together using phenol-formaldehyde-based glue. Although, according to existing standards, plywood of this brand is allowed for indoor work.
Plywood varieties
In accordance with GOST, there are four types of plywood:
Of course, when choosing the best option for leveling a wooden floor, you should rely on your capabilities. The only thing that can be definitely noted is that grade 4 plywood is not suitable for flooring. The first option is ideal, but in terms of the optimal price-quality ratio, the option of choosing second grade plywood becomes more suitable.
Degree of plywood surface treatment
The surface of the plywood sheet can be sanded or unsanded. This point is reflected in its marking:
- NSh – marking for unsanded plywood;
- Ш1 – plywood, sanded on one side only;
- Ш2 – marking for plywood, sanded on both sides.
Plywood emission class
On sanded plywood mandatory make markings with the emission class of free formaldehyde:
- E1 – marking indicates that the presence of formaldehyde is less than 10 mg per 100 g of dry plywood mass;
- E2 - marking indicates the presence of formaldehyde in an amount of 10-30 mg per 100 g of dry plywood mass.
From the data obtained, we can draw a final conclusion that the best option for leveling would be second-grade plywood with the markings Ш1, ФК, Е1 and a sheet thickness of 10-12 mm.
Tools for leveling wooden floors with plywood
High-quality leveling of plywood floors is impossible without the use of special tools. In addition, you need to have some skills in working with the material and experience with some tools.
To complete the work you will need:
- Level;
- Self-tapping screws;
- Screwdriver;
- Roulette;
- Jigsaw.
Preparatory work
Before starting work on plywood, it is necessary to check the condition of pipes, electrical wiring and other communications running under the floor. Once all work is completed, there will no longer be free access to this space.
Sheets of plywood must be kept for several days in the room in which the work will be performed. This will allow you to achieve the same humidity in the material used and in the room, which will avoid deformation of the sheets after installation. If the room is regularly heated, then the plywood sheets are placed on edge and kept for at least two days. When working in a room that is heated periodically, the sides of the material should be slightly moistened with warm water. Keep them at room temperature for 24 hours.
The choice of plywood sheet thickness depends on what kind of coating will be used for installation in the future. When choosing a soft covering such as linoleum or carpet, you can use thinner sheets. In this case, you will not achieve complete leveling of the floor, but you will still get rid of large differences. If you plan to lay laminate flooring, then you should definitely choose 10-12 mm plywood. In this situation, you can make the floor perfectly flat by correcting all surface irregularities.
Step-by-step instructions for leveling a floor using plywood
Laying plywood on a wooden floor must be carried out in strict accordance with the basic rules:
- It is necessary to ensure a distance of about 10 mm between the plywood sheets and the wall;
- Damper (expansion) joints between adjacent sheets of plywood should reach 2-3 mm.
First step
We install beacons, the role of which is played by self-tapping screws. They must be located over the entire surface area and screwed in to the required height. To put it simply, we can say that screws need to be screwed into the corners of squares with sides of 20-30 cm ideally, but you can limit yourself to 30-35 cm.
Important! The thicker the sheets of plywood used for installation, the sparser the beacons should be placed.
Second step
Next, you need to lay plywood logs, which are strips of material 3-4 cm wide. We attach them to the floor using self-tapping screws or special glue intended for wood. Care must be taken to ensure that the laid joists do not sag. In those places where there is space between the joists and the floor, you should place pieces of plywood of the required thickness, pre-lubricated with glue.
Third step
Before further work you need to wait until the glue dries completely. Sheets of plywood should be cut into squares with sides of approximately 60 cm. At this stage, a thorough analysis of the resulting blanks is carried out. When examining the ends, initial signs of delamination of the material are revealed, which are very often not noticeable on whole sheets of plywood. Low-quality material must be replaced, as its use will negatively affect quality characteristics entire coverage.
Fourth step
We lay squares of plywood on the resulting grid of joists. It should be remembered that the joining of adjacent sheets of plywood must necessarily take place on the joists. We do the installation using a technology similar to brickwork, that is, in such a way that there is no intersection of four planes at one point. We accurately cut the plywood to the required size. At the same time special attention should be given to places with a complex configuration, where there are arches, various protrusions and other surface features.
Useful advice! To save material when cutting, you can lay sheets of plywood on the floor before installing the joists. Then use chalk to mark the joints of the squares of material and lay the joists in the required place.
Fifth step
At the final stage, we fix the plywood sheets to the joists using self-tapping screws with a countersunk head. The fastening points are pre-drilled and countersinked. This will prevent the heads from squeezing out the material.
The use of this technology for leveling a wooden floor increases its height by only 2-3 cm.
Further surface treatment depends on the type of future floor covering. If you plan to lay laminate flooring, you must first lay the underlay on a plywood base. When choosing linoleum as a floor covering, you should walk a little over the surface with a sanding machine, carefully treating the joints of the sheets and the fastenings of the plywood to the joists. If the choice is carpet, then the plywood should be coated with several layers of varnish.
Leveling the floor using plywood sheets allows you to get a smooth, durable surface instead of the old uneven floor, fully prepared for laying any floor coverings. When the work is carried out carefully and consistently, a high-quality surface is obtained, which will become the basis for the implementation of the most daring design solutions.
In a wooden house, bathhouse, multi-storey residential areas, a flat surface is required for laying floor coverings. If the base is a wooden floor, then plywood is laid on them. Leveling a wooden covering with plywood is the topic of our conversation about finishing materials. In it we will share our experience of installing it on wooden floors.
First you need to determine the condition of the wooden floors, whether there are large differences in height between the boards.
If the floors squeak, you need to pour graphite powder with talc into the cracks or drive wooden wedges into them.
If this does not help, then secure the defective boards with self-tapping screws or dowels with screws.
If you cannot level out significant differences in height with your own hands, then you need to dismantle the rotten structure, replacing the destroyed boards with freshly planed ones.
Do-it-yourself leveling of a wooden floor with plywood
First of all, we lay out plywood sheets on a wooden base in a checkerboard pattern for fitting and determining the guide joists. Let's draw these lines.
We already have an outline of the location of the horizontal bars.
Number the plywood sheets and the floor so as not to be confused during installation.
The logs are square bars with a long side of 40-60 cm. Instead of bars, you can use boards or plywood sheets cut into strips.
Transverse strips are attached to the logs in approximately 40-50 cm increments. Metal corners make the connection of the longitudinal and transverse strips strong and reliable.
Using a level gauge, we level the lattice base. To ensure that the logs are at the same level, we place wooden spacers under them. And then, using metal corners and self-tapping screws, we attach the logs to the plank floor. You can also use dowels as lag fasteners, which are 3 times the thickness of the lag.
Between the lags we fill the free surface with sand or a homemade mixture consisting of sawdust and PVA glue.
We spread it in two layers and leave it for the leveling compound to harden.
If the logs are low or in the form of slats, then we use roofing felt or roofing felt. Only after this we begin to attach the plywood.
Installation of plywood on mini joists
Another method of leveling the floor with plywood in a wooden house is to use mini-lags.
This method is very accurate. It is carried out only by masters of their craft and engineers. The slightest inaccuracy in the calculations will make the design unreliable. Each element of the building is calculated separately using special instruments.
Mini-logs (slats) are laid lengthwise and crosswise in the form of a lattice. This method is used when there is a large slope of floors and significant differences in height - up to 8 cm. First, sheets of plywood are laid out for fitting to make markings. The thickness of the supports and the angle of inclination are calculated using formulas and programs.
Installation of plywood on the sheathing of point supports
The fourth way to lay plywood sheets is by lathing point supports. The blocks are cut from boards or plywood and laid in the form of a grid. The step between them is much smaller than with strip supports. This method is less accurate than using a lag.
Leveling a wooden covering with plywood under linoleum
Linoleum is a capricious coating; all roughness, unevenness and debris will be visible on it. Over time, due to its elasticity, it will take the shape of the base, enveloping the protrusions and recesses. Therefore, a perfectly flat surface is required for linoleum flooring.
Preparing the wooden covering. Best to spend wood floor scraping.
To protect yourself from dust, you need to wear a respirator and headphones to protect yourself from noise.
You need to work with a looping machine, starting from the corner of the room, moving like a snake to the other end of the room. The corners are processed manually.
Putty is needed to treat cracks and cracks in wooden floors.. When the mixture dries, you should repeat the scraping.
Collect dust after the process with a vacuum cleaner.
The wooden covering is treated with antiseptic agents. The top is varnished.
You can also scrape floors using a planer. But this is a more complex process. Floor scraping is carried out if the height differences are insignificant. In this case, plywood is not needed. It is also not needed when leveling a wooden floor with dry mixtures, which are applied to a sanded floor.
If the floors are located on a slope, plywood panels are required.
We take self-tapping screws and screw them into the wooden floor at a distance of 20-30 cm from each other. These are our beacons on which logs and plywood sheets will be placed. The screw heads must be at the same level.
We cut the plywood sheets into squares with a side of 60 cm. It is very important to check the sheets so that there are no cracks or chips.
We lay out plywood beams 3-4 cm wide. These are logs. They serve as support for plywood panels. If there is a gap between the joists and the floor, you can place a thin piece of plywood. Attach the joists to the floor using wood glue or self-tapping screws. Expanded clay can be poured between the joists. It will be a kind of insulation for the floors.
We begin the installation of plywood sheets. We lay out the plywood in a checkerboard pattern with an offset. We strengthen it with screws inserted into dowels. To ensure a neat finish, it would be a good idea to drill holes for the dowels before laying the plywood panels.
When laying plywood, the screws are simply screwed into the dowels. Plywood sheets are fixed to the joists. It is very important to step back 2 cm from the wall and leave a gap between the plywood panels. Then seal the seams with putty or mastic. When laying plywood, you need to remember that only three edges of plywood sheets can converge at one point, no more. After leveling the floor with plywood, you need to sand the floor and varnish it. You can lay a backing and linoleum on top.
Leveling wood flooring with plywood under laminate
Leveling a wooden floor with plywood under laminate is almost the same as under linoleum.
First you need to remove the wooden baseboards with a nail puller. Tidy up the room, sweep, wash the floors. We make 2-3 holes in the floor in different places of the room to determine the height of the base of the screw. We make beacons in the form of self-tapping screws. The thicker the plywood, the greater the distance between them. The height of the log is 30-50 mm. We screw the plywood to the joists with self-tapping screws.
Offers a wide selection of construction, finishing materials and household goods.!
The floor is a particularly important surface in any room. The main thing is that it is smooth, aesthetically beautiful and does not lose its properties for a long time.
An important step in renovating a room is leveling the floor. To lay any floor covering, be it laminate, tile or linoleum, a flat base is required. After all, it determines how long a modern coating will last.
The easiest way to have a beautiful front lawn
You've certainly seen the perfect lawn in a movie, on an alley, or perhaps on your neighbor's lawn. Those who have ever tried to grow a green area on their site will no doubt say that it is a huge amount of work. The lawn requires careful planting, care, fertilization, and watering. However, only inexperienced gardeners think this way; professionals have long known about the innovative product - liquid lawn AquaGrazz.
Different ways to level the floor
You can level the floor surface using different methods, each of them has its own pros and cons. Let's consider each of them separately.
Methods for leveling the floor surface:
How to choose the right plywood sheets for the floor
Plywood is practically indispensable building material. This is due to the following factors:
- relatively cheap price;
- quick installation;
- Perfect for eliminating various irregularities.
When choosing plywood sheets, you should pay attention to the following parameters:
- it must be made from environmentally friendly materials;
- its surface must be moisture resistant;
- In order to save time, it is better to choose plywood that has already been sanded.
There are 4 types of plywood:
- The best one is that there are no defects, but small cracks are possible.
- It may have wood inserts and glue may be present.
- The variety already has knots.
- The lowest quality; this plywood sheet has many different defects.
Of course, the price of plywood directly depends on the grade. After all, the better quality the product, the higher the cost. Grade II is the most preferable for leveling floor coverings (based on price-quality ratio). The latter variety is not recommended for use for these purposes.
Types of floor leveling with plywood sheets
In order to make the base of the floor level, you can use two methods:
Method 1 is alignment along additional sheathing (using joists);
Method 2 - without using lathing.
There are two types of floor base:
- concrete;
- wooden.
Leveling the floor concrete base
When laying plywood on a concrete floor, careful preparation is required. After all, concrete is a rather complex material. Before starting work on leveling the base, you should determine how wet the surface is. To do this, you need to lay a small piece of film on the concrete and press it, after a couple of days you should check whether condensation has formed on the inside of the film. If this happens, then the plywood surfaces should be treated with additional agents against fungus and mold.
Technology for leveling floors using joists
For this work you need tools:
- building level;
- roulette;
- perforator;
- self-tapping screws;
- jigsaw;
- electric or cordless screwdriver.
Before laying the plywood sheets, prepare the base. The old surface should be removed down to the concrete, cleaned, and vacuumed. The concrete surface must be perfectly clean and dry. Now, using a level, you need to determine the boundaries of the new surface, and you can proceed to preparing the lag. For them you need to purchase ready-made wooden blocks. They can be purchased in specialized stores or construction markets. When purchasing, you need to pay attention to what kind of wood they are made of and determine the degree of dryness.
Under the beams, you need to prepare wooden pads with a width of 10 to 15 cm, a length of up to 20 cm, and a thickness of 2.5 cm. The logs are laid across the direction of the light that falls from the window, maintaining a distance of 40 to 50 cm.
The space between wooden blocks can be filled with sound and heat insulating materials so that the resulting floor surface is not only warm, but also silent. When installing joists, you should leave a little space between the wall and the beam so that changes in room temperature do not cause deformation of the floor covering.
The sheathing must be done exactly according to the pre-marked floor level. After the concrete surface has been covered with joists, you should begin attaching the plywood itself. The prepared surface of the plywood sheet should be divided into pieces approximately 75x75 cm in size using an electric jigsaw.
These small pieces of plywood must be screwed to the prepared joists. Be sure to leave a gap of 2 to 4 mm between the plywood. If this is not done, the floor will creak after some time.
This happens because wooden structures can change their volume. The process depends on the time of year and the level of humidity in the room. And the gaps will allow the tree to freely change in size without changing the integrity of the floor.
To screw the plywood, you need to use self-tapping screws and a screwdriver. This should be done by leaving a distance of 50 to 100 mm between the screws.
If you have to level the floor in the hallway, you need to lay out the joists across the movement. This will make the floor surface more stable and reliable.
Leveling with battens should be used if differences in the floor surface are more than 50 mm.
If the differences in the floor are no more than 10 mm, then it is possible to attach the plywood directly to the concrete surfaces without preliminary lathing.
Technology for leveling concrete floors without using joists
For such cases, plywood should be chosen with a thickness of more than 18 mm. This is the simplest method compared to the previous one.
To secure plywood to the floor surface, you can use the following methods:
- using glue;
- regulation.
To attach plywood sheets using adhesive solutions, it is necessary to take into account that there should be no significant level differences on the required floor surface. The concrete surface must be perfectly dry before applying the adhesive, with minimal moisture.
The regulated method is not particularly popular. It uses specialized adjustable racks to level the surface. Plywood is laid in two layers on wooden blocks. The thickness of the first layer is 0.2 cm, and the second layer should be slightly smaller.
Leveling the floor surface with plywood on wooden bases
Without using lag
For a wooden covering, plywood can be laid quite simply - screw the sheets to the base. The main thing is that the foundation is strong. For this method, plywood must be purchased with a thickness of at least 10 mm.
When starting to level the wooden floor, you should step back from the wall about 20 mm. The gap between the plywood sheets should be from 3 to 8 mm. When laying them, you need to imitate a brick laying - the sheet should be laid offset to the next one by at least ¼ of the sheet of the previous row.
Leveling using joists
It is also possible to level the wooden subfloor along the joists. True, this method is the most complex and time-consuming. But on such a surface you can safely lay laminate, tiles and other types of flooring. Thus, we will get a floor surface that is perfectly flat for any modern floor covering.
To level the wooden subfloor along the joists, you must first dismantle the old floor covering. After this procedure, you should inspect the existing logs; they will probably need to be replaced. Now you should longitudinally sheathe the floor surface with beams in 60 cm increments. Plywood sheets are attached directly to the joists so that the joints rest on the supports.
Before sewing on the plywood, you need to lay an additional layer of insulation. For this you can use polystyrene and mineral wool. Then lay a vapor barrier on top. The plywood is mounted on the bars in the same way as when leveling concrete floor bases.
Finishing the floor surface
After laying the plywood sheets using one of the above methods, you should proceed to finishing the floor surface.
Checking the correct installation of plywood:
- carefully inspect the floor surface;
- check for gaps between sheets;
- sheets of plywood should not fit tightly to the wall;
- Check the horizontal surface with a building level. It must be even, only a difference of 2 mm is allowed.
- The entire area of the floor covering must be tapped with a mallet. If suddenly a dull sound appears, then it is necessary to remove this part of the plywood sheet and redo it. The presence of this sound indicates emptiness underneath the material.
After checking the work done and eliminating all defects, if any, you can begin sealing the joints with putty. The floor surface is cleaned with a vacuum cleaner and covered with primer.
To summarize, it should be highlighted general rules work on working with plywood sheets:
Thus, having considered all the possible methods of how to level a floor with plywood on wooden and concrete bases, we can conclude that this option is very affordable, light, strong and quite durable. After preparing the surface, you can safely go to construction supply stores and choose a modern coating that suits your liking.
The use of plywood is rightfully considered an economical and well-established method of leveling the floor surface in wooden buildings. Dry screed using sheet material does not require incredible labor costs and does not require significant financial investments. There are no noticeable technological interruptions in the process that delay the finishing process. But there are nuances that an independent performer needs to know about. Before you begin the planned repair, you should find out how to level a wooden floor using plywood sheets in order to avoid unwanted and very expensive alterations.
The videos will demonstrate in great detail how to create a perfectly smooth surface using factory adjustable systems. The video is aimed at owners of city apartments with concrete floors.
Fundamentally, the method of installing adjustable joists with plywood or plywood sheets with anchor posts on a wooden base does not differ from the scheme for installing them over cement slabs.
If the owner of a country bathhouse has a surplus cash, he may well use ready-made adjustable kits. Leveling in the recreation room, billiard room or dressing room will be carried out quickly and without much effort. However, we certainly won’t classify adjustable plywood and joists as cheap methods. Let's better explore budget options.
Methods and techniques for leveling with plywood
The choice of the optimal technology for leveling a wooden floor with plywood determines the condition of the floors and the degree of deviation of the surface “relief” from the specified construction requirements norms:
- with a difference in height levels of 2 mm found on an area of 1 m2, even for laying linoleum, which is extremely sensitive to deviations, leveling is not required. Treatment with acrylic sealant or puttying with a homemade mixture of moistened sawdust and PVA glue would be quite sufficient;
- with uniform deformation of correctly laid floorboards with a difference in height levels of 5 mm, leveling the floor with plywood can be done by attaching the sheets directly to the plank floor;
- height differences of more than 1 cm, but not more than 8 cm require the creation of point or strip supports. Essentially, the process consists of constructing a sheathing from timber or from slabs replacing solid logs, for the manufacture of which thick plywood or boards are used.
Correct laying means that the builders alternated boards with different directions of the pattern of the annual rings of wood in accordance with technological requirements. This means that bulges-humps or concavities-boats on the floor appeared through one or two boards.
If it is not possible to level a wooden floor without problems with your own hands due to too large fluctuations in height, the structure must be disassembled and built from new lumber. Such serious deviations probably have no less serious reasons.
It is important to note that plywood can be used for dry leveling only if technical specifications no complaints about gender.
How to determine differences in height?
A laser device is a great thing, but the quality measuring tool in this case, a two-meter level gauge will be more effective. With its help it is more convenient to study the surface. It is necessary to mark the points in the corners of the room being repaired, find and mark the centers of the lines connecting the floor and walls, and the center of the room. Having divided the room into specific segments, it is necessary to examine each area. Evaluating the recorded results will paint a picture of the upcoming repair.
Regardless of the scope of the work to be done, inspection and repair of the foundation must be carried out. It is necessary to eliminate the creaking, update the fasteners, replace damaged elements, and check the functionality of the “underground” communications.
Method #1 - “the simplest” without installing lag
Before laying plywood, it is necessary to provide the opportunity to “get used to” the conditions of the upcoming service. Material intended for arranging a regularly heated room needs to stand on the edge for a couple of days where it will be laid. In a room that is not spoiled by constant heating, sheets moistened with warm water should stand for at least a day.
All wood floor elements and dry screed materials based on wood veneer or fibers are pre-treated with an antiseptic.
The most the easy way Leveling the floor with plywood is considered a method without installing joists. Installation of a support beam is not required, since its function will be adequately performed by the evenly distributed tubercles of curved floorboards. In addition to plywood, DSP or GVL boards are suitable for such leveling.
There is no point in leveling a wavy, deformed fiberboard floor. During operation, the material will sag and repeat all the grooves with the tubercles of the rough base.
For a plank floor with floorboards up to 20 cm wide, each of which “swells” evenly, we will buy plywood 8-10 mm thick. If a board more than 20 cm wide was used for flooring, and also if not every floorboard rests with a convex “hump” on a plywood sheet, sheet material will be required with a thickness of 18-20 mm.
The sequence of actions for leveling the subfloor using plywood:
- We will place bosses along the perimeter of the repaired floor to form a mandatory two-centimeter distance from the walls.
- We lay plywood sheets with a gap of 3-8 mm between them to absorb movements caused by moisture fluctuations. When laying several rows, we imitate brickwork. That is, we place the slabs of the next row offset to the slabs of the previous one. There should not be a cross-shaped intersection of four butt seams at one point. Minimum size offsets – a quarter of a sheet, maximum half.
- We attach them to the “ridges” of the boardwalk at the points with maximum height. We try to distribute the attachment points evenly, focusing on the distances between the convexes identified as a result of measurements.
It is recommended to drill holes for fasteners in advance in two steps. First you need to use a drill whose size is equal to the diameter of the screw. Then you need to make a hole with the diameter of the cap so that it can be completely recessed in the plywood sheet. The dowels along the perimeter of the plywood sheet should be at least 2 cm away from the edge.
Sheets of plywood with one-sided roughness, intended for subsequent laying of the final coating, are recommended to be laid with the unsanded side up to improve the adhesion of the coating to the leveling layer. It is better to turn the sanded side if you plan to simply mask the screw heads with acrylic sealant and open the plywood with varnish on top.
Method #2 - with a tape support device
The technology consists of constructing a sheathing of longitudinal joists and crossbars aligned in one horizontal plane. The perimeter logs are placed at a distance of 3 cm from the walls. The laying step of the longitudinal components of the frame system being constructed determines the size of the plywood sheet. Usually its values vary from 40 cm to half a meter.
Example - if the side is 152.5 cm, then the optimal distance between the axes of both the joist and the crossbars will be 48 - 50 cm. If the side is 122.0 cm, it is recommended to leave 37 - 40 cm between the axes of the support beam.
Step by step guide:
- Let's start with fitting. Lay out the plywood without fastening, holding standard scheme brickwork and ensuring clearances. Let's outline the outline of the slabs; these lines will become guides for future marking of the location of the logs. Don't forget to number the sample sheets.
- Using the markings made on the floor, we first install the joists along the walls. The optimal material for installing strip sheathing under plywood is considered to be a square beam with a side of 40 to 60 cm, variations are allowed. If it is undesirable and not necessary to raise the floor too much, joists can be made by cutting plywood into strips, or using second-grade boards.
- We install transverse jumpers with a step calculated according to the dimensions of the sheet. They are attached to the joists with self-tapping screws, preferably using metal corners.
- We align the logs and transverse elements vertically in a single plane according to the readings of the level gauge. Those wishing to find out how to properly level the surface of an old wooden floor should adhere to the requirements specified in SNiP number 3.04.01-87. According to this collection of standards, it is prohibited to drive wedges made from leftover lumber under the joists. Leveling is done by adding sand, in case of minor deviations by laying roofing material or roofing felt. Most often, a single plane of the joists is achieved by placing wooden spacers under them, such as point supports.
- After leveling, the joist system is attached to the base with galvanized metal corners, can be used to fix the sheathing with dowels, the length of which is three times the thickness of the joist.
- We complete the leveling by laying and fastening the plywood.
The space between the joists can be filled with additional insulation or a homemade screed made from wet sawdust mixed in half with PVA glue.
Apply the mixture, the consistency of thick sour cream, in two or three layers and wait for it to completely harden for two days. In such cases, you can buy thinner plywood for leveling.
Method #3 - alignment with a mini-lag device
It is used to level floors with a slope and with significant differences in heights of up to 8 cm. It consists of installing slats and wooden pads in order to create a unified support system for plywood. Without accurate engineering calculations, it will be extremely difficult for the contractor to cope with a very difficult task.
First you need to try it on, and then carefully calculate the size of each supporting element using the lines marked on the floor. It is necessary to calculate the height and select dimensions very carefully, since all elements of the supporting structure will be different.
Method #4 - with point support sheathing
The point method consists of installing individual support blocks, cut from boards, OSB boards or the same plywood. The thickness of the block is selected in accordance with the difference between the created flat surface and the actual level. Ultimately, the support system should form a kind of mesh that replaces the strip sheathing.
Since it is inferior to the tape type in terms of reliability and stability, shabby linings are installed with smaller increments. You should get some kind of cells with an imaginary square size of 30 cm for sheet material up to 14 mm thick, 45 cm for thick plywood.
And don’t forget about providing underground ventilation! After removing and installing the baseboard, you need to drill ventilation holes in it at pre-existing points. Cover the holes with a ventilation grill.
Have you figured out the best way to level your wood floor with plywood? There's little to do, all that remains is to prepare morally and technically and begin implementing plans. Surely everything will work out great, because the repair procedure does not present any particular difficulties.
Modern floor coverings (laminate, cork, linoleum) require a flat base surface for installation. In older buildings, the foundation often requires leveling. There are many methods for this, one of which is leveling the floor with plywood.
For high-quality installation of flooring material, a level base is required. This will save you from the need to place felt or bars under equipment and furniture.
Leveling a wooden floor with plywood is necessary to remove bumps, depressions, and also to eliminate curvature in the surface area.
Almost all flooring materials react poorly to defects in the rough flooring. Laminate flooring without a prepared floor will, after some time, creak, become loose and the board will become unusable. On linoleum, after a while, without first leveling the floor with plywood, all the bumps and flaws that are under the finishing material will be visible.
Installing furniture and appliances will also have problems when placed on an uneven floor. A simple installation of a sofa can turn into a multi-hour problem with placing felt and pieces of wood under the legs for leveling.
Plywood - flooring materialPlywood is a durable, multi-layered wood material. Due to its affordable price and excellent technical characteristics, it is often used in construction.
This material is chosen as a subfloor due to many factors. Plywood has affordable price per m2, fits well without additional time and money for leveling the floor. Due to the arrangement of fibers in different directions, it is a fairly durable material. It can be used not only to obtain a flat floor, but also to make minor repairs to eliminate flaws and defects.
How to buy plywood correctly?
Plywood of different thicknesses When purchasing plywood used for leveling, you should take into account the following parameters:
- Brand;
- Class;
- Variety;
- Thickness;
- Manufacturer of the material.
Depending on the type of premises, preference should be given to different brands. For residential premises, preference should be given to the FC or FSF brands. This plywood is safe because it contains no phenolic compounds. For wet rooms, it is preferable to choose FSF brands. This plywood is moisture-resistant and resistant to mechanical stress.
Differences in plywood grades The grade of plywood indicates the level of release of free formaldehyde particles into the air. There are two classes:
- E1 contains 10 mg of formaldehyde per 100 g of wood material;
- E2 contains 30 mg of formaldehyde per 100 g of wood material.
For living rooms it is preferable to buy E1.
Plywood is produced in 4 grades. Grade 1 material is high-quality plywood. The fourth grade is a material with the presence large quantity flaws, chips and knots. Professional craftsmen recommend using grade 3 and 4 plywood for rough flooring. For the main floor, grades 1 and 2 are preferable.
Varieties and classification The thickness of the material is selected depending on the leveling method, the curvature of the floor and the coating laid on top. Creating a subfloor for laying linoleum and carpet allows you to choose a material up to 10 mm thick. Under laminate or parquet, a plywood thickness of at least 12 mm is required to level the floor.
When choosing, focus on these indicators. If you choose the wrong thickness, the sound insulation will decrease and the floor will quickly become unusable.
The manufacturer determines the quality of the plywood. European manufacturers guarantee excellent quality of the produced material. But Chinese-made sheets do not always meet consumer requirements.
Floor leveling scheme Also, plywood can have a sanded or unsanded side. If it is used as a subfloor, then it is laid so that there is a surface at the top without sanding. This will ensure good contact with the finishing material.
When using plywood as a finished floor, the top layer must be sanded for subsequent opening with varnish.
What tools are needed for the job? Without the appropriate tools, it is impossible to properly level a wooden floor with plywood. To do this you will need the following devices:
- Hammer;
- Screwdriver;
- Floor level;
- Roulette;
- Hammer;
- Jigsaw;
- Screws
- Marker for marking.
It’s good if you have even minor skills in handling construction tools and materials.
Before laying plywood, assess the condition of the base and check the floor level.
Concrete base defects and ways to eliminate them An inspection of a wooden base consists of removing creaks, replacing fasteners, updating boards in the damaged part of the floor, assessing the condition and replacing underground communications if necessary.
The concrete base is checked for defects on the surface. The level determines the curvature. Before laying plywood on a concrete base, check the surface for moisture by covering it with film for several days.
Laying on old joists Experts report that depending on the difference in floor height, they choose the method of laying plywood sheets.
If the difference in height is up to 2 mm, there is no need to level it. Changing the floor level to 5 mm per m2 allows you to level it with plywood, laying it directly on a wooden base.
A large difference in the height of the concrete floor up to 8 cm requires the installation of strip or point lathing for leveling with plywood.
A high floor difference requires dismantling the old covering and replacing it with a new floor.
Plywood finished floor Knowing the simple rules for leveling plywood various types floors, you can easily do the job yourself. When laying plywood as a finished floor, the sheets begin to be installed from the middle of the room. The plywood must be secured with self-tapping screws at a distance of at least 2 cm from the edge of the sheet. After the process is completed, the coating is sanded and varnished.
Creating a subfloor using plywood does not impose any special requirements on the fastening and arrangement of sheets. If two layers of material are assumed, then it is laid with the sheets offset to prevent the seams of the top and bottom rows from matching. There are a number of methods for laying plywood sheets over concrete or wood floors.
Laying sheets without logs It happens that a concrete floor requires not only leveling, but also insulation. For this, an option without the use of lag is suitable, which is considered one of simple ways leveling the floor with plywood. Work with plywood material begins only after it has been kept in the room for several days to get used to the room conditions.
The base for laying and the plywood sheet are treated with an antiseptic before it is laid. To create the gap required by the technology, bars are placed around the perimeter of the room.
Sealing seams and irregularities The plywood sheets are placed on the floor so that they are offset relative to each other (as when laying bricks). The material is secured with screws evenly along the protruding points of the plywood.
All fasteners and seams are covered with sealant, after which the surface is puttied.
For a wooden floor that is not loose and in good condition, you can also use plywood leveling without using joists.
Fastening with self-tapping screws Wood plank floors are treated with sealant or putty material. It is leveled using sand or sawdust mixed with resin. A vapor barrier film is laid on top, on which plywood is already laid.
To ensure that after fixing the plywood with screws, they do not protrude above the coating, the holes are made in several approaches. First, a hole is drilled to the size of the screw, and then it is processed so that the head of the screw is level with the surface of the plywood sheet.
Laying on joists Leveling the floor with plywood over strip sheathing can be used for laying under laminate, tile or linoleum. This support is created using square bars and plywood sheets. The logs are laid in increments of 30-50 cm, and at a distance of 20-30 mm from the walls. The cross bars are secured to the joists in a checkerboard pattern using screws. To add rigidity, you can secure them with metal corners.
To create sound and heat insulation, wood shavings mixed with glue are poured between the sheathing. This mixture dries within 2-3 days. You can also use expanded clay or mineral wool for backfilling.
Laying insulation between joists The plywood is secured to the support with self-tapping screws. After this, you can lay any floor covering.
The method of leveling the floor with plywood over mini joists is chosen when there is a slope or the surface difference is up to 8 cm.
Adjustable joists The floor surface is marked for the installation of bars and pads, which create an ideal structure for laying plywood sheets. This work requires careful calculations of the height of each support element with markings on the floor and preliminary fitting.
With this type of flooring, all structural elements will be of different heights. Working using this method is not difficult, but it requires a painstaking approach.
Layout diagram for point supports This leveling method requires supports, self-tapping screws, two layers of plywood covering and glue.
First, sheets for marking and numbering are laid out on the base. The sheets are removed and the height of the finished floor is marked on the wall.