Laying OSB on a concrete floor. Self-tapping screws for OSB - choose and calculate correctly

OSB flooring is now very popular. It has many advantages and makes it possible to reduce the repair time. OSB is a highly compressed board that consists of several layers. The raw materials for the production of this material are long wood chips (6-9 cm each) obtained from coniferous trees. tree species(pines, sometimes aspens). The strength of OSB is ensured by the different orientation of the chips. For example, in the middle it is placed perpendicularly, and in the outer layers – along the length. Pressing is carried out under the influence high temperature and pressure. At the same time, the material is impregnated with resins and waxes, which ensure its moisture resistance.

OSB has the following advantages:

• and processing.
• During sawing or drilling, the sheet does not begin to crumble.
• No warping during operation.
• Homogeneous structure.
• Very high strength sheets that can even replace wood materials. Please note that the material can withstand enormous loads if distributed correctly.
• No knots.
• High degree of resistance to moisture.
• Long service life - about 20 years.

As you can see, OSB is an excellent material for arranging both rough and finished floors.

Production of OSB boards and use for flooring on joists

Types of material

Before you start working with sheets, you need to understand what they are:

1. OSB - 1. This is the least durable and thinnest board. It can only be used in rooms where there is never an increase in air humidity.
2. OSB – 2. Such sheets can be used for arranging load-bearing structures only in dry rooms.
3. OSB – 3. This material is well suited for arranging load-bearing structures in rooms where the humidity level is often high. This type of product is most often used in construction.
4. OSB – 4. Such sheets must be laid in those rooms where a very strong mechanical load is expected on the floor. The thickness of such a slab is maximum. In addition, the material is carefully treated with wax and resins, so it is not at all afraid of moisture.

Comparison of OSB with other wood materials

Specifications

Before buying OSB, you need to consider its technical parameters:

• Resistance to moisture: depending on the type of coating, this parameter ranges from 12-25%. The most resistant to moisture is the slab with the lowest rating.
• Mechanical strength. The most reliable slabs can be considered class 3 and 4. In general, the strength of the product along the transverse axis ranges from 1200-1800 N/mm2, and along the longitudinal axis - 2500-4800 N/mm2.
• Product weight. One slab can weigh from 12 to 43 kg.

OSB-3 characteristics table with different thicknesses slabs

• Material thickness: 0.6-2.2 cm.
• Ecological cleanliness: according to laboratory studies different organizations, the content of harmful components in the product does not exceed permissible limits.

The cost of the slab depends on its technical parameters and amounts to 420-780 rubles. a piece.

How to choose the right product?

Before laying OSB, you need to decide on the following parameters:

1. Type of base. The thickness of the material depends on this.
2. Product size.
3. Necessary qualities (for example, if you are laying OSB in a dry room, then you may not need such quality as moisture resistance).
4. Manufacturer. It is best to give preference to European, Canadian and North American manufacturers. Their products are certified by international organizations.

Use of OSB for finishing and rough finishing of floors

OSB-3 is most often used for flooring.

How should the material be treated for different types of flooring?

OSB floors can be rough or finished. In the second case, the surface is simply sanded and varnished. Naturally, the gaps between the sheets should be invisible. If you decide to lay another facing material on top of OSB, then the base must be pre-prepared depending on what kind of coating you will use:

• . The base must be level, especially at the junctions of the slabs.
• or . In this case it is better to use thin slabs, which will make the transition between them smooth and almost imperceptible. Additionally, it is treated with a sealing agent. Please note that if one sheet of OSB is laid on the floor, then the compensation gap is arranged on the side of the walls.
• . When choosing such a facing material, it is necessary to take into account that the base for its installation should be as strong and level as possible. Sheets should be secured so that they are motionless. If you are laying OSB on logs, then in this case they should be mounted at a short distance from each other.

Features of installation of the rough foundation

So, if you decide to use OSB boards for subfloor equipment, you need to decide what you will lay them on: concrete or wooden joists. In any case, the most acceptable material will be OSB - 3. If the base for installation is a concrete screed, then the thickness of the sheet may not exceed 1 cm. In the case of laying on wooden logs, this parameter can reach a maximum of 2.5 cm. The material is attached to concrete at using dowels. You can fix it on the tree using self-tapping screws. Please note that the fastener heads must be recessed into the slab. This way you will achieve a perfectly even surface. If you need to achieve maximum strength of the base, then the sheets should be laid in 2 layers. At the same time, the seams in the lower and top layer should not match.

During installation, pay attention to the quality of the joints. They need to be leveled and smoothed as much as possible. For this purpose it is used elastic sealant. The arrangement of the subfloor is done as follows:

• To begin with, logs are installed on the floor.
• Now you can screw additional bars to them (at the bottom). Their cross section should be 5x5 cm.
• The side that will be in contact with concrete or facing the ground must be additionally treated with an antiseptic or bitumen mastic(one layer is enough).
• Fastening plates. This can be done using special nails, screws or glue.
• . This can be polystyrene foam or mineral wool. Expanded clay can also be poured between the slab and the ground.
• Laying an additional OSB board, which will serve as the basis for subsequent cladding.

Subfloor pie from OSB boards

Before laying the first layer of sheets, it is necessary to waterproof the floor.

The material can also be laid on a dry screed. The filling must first be leveled along the beacons. Next, it is necessary to install a layer of OSB, on top of which the same sheets are laid, only with the seams shifted. They can be fixed using self-tapping screws, the pitch between which is 15 cm. Please note that the fasteners must be screwed along the edge of the second layer.

A floor made from OSB panels is an excellent base for any finishing layer. You can lay parquet, panels or ceramic tiles. OSB sheets, also known as OSB and OSB boards or sheets. This material has increased mechanical strength and resistance to moisture, and is also characterized by good thermal insulation and sound insulation. The advantages of the chosen solution include relatively simple installation. In this article we will talk in detail about how to properly lay OSB sheets on the floor.

In what cases are OSB sheets laid on the floor?

There are a variety of flooring materials and smoothing materials to choose from. Traditionally, mineral mixtures are used in residential premises: grade 400 cement with sand or ready-made dry mixture. This ensures the reliability and durability of the rough surface on which decorative flooring can be laid.

However, the use of concrete screed is not always possible, and special solutions with a leveling effect are not cheap. An alternative to both materials is OSB floor board, which provides permissible limit durable and easy to handle. Although, such a solution will not be cheap either. It should be applied under the following conditions.

• The base of the room is well insulated and does not allow pouring concrete.
• The housing is located in an area with a cold winter climate, which forces the cement-concrete floor to be additionally insulated using a layer of OSB or creating an artificial void from sheathing and insulation.
• Noticeable irregularities (chips, holes) that require leveling before cladding design materials(linoleum, carpet, etc.);

OSB is favored by its resistance to rodents and mold, relative immunity to stress and friendliness to all types of finishing.

Not only a concrete floor, but also wood flooring, wooden and metal carcass, as well as other types of fairly strong foundations.

Selecting the thickness of OSB sheets when laying on the floor

Manufacturers offer material standard sizes, but there are limitations. Thus, the size range in length is 244-280 cm, and in width from 60 to 250 cm. From the point of view of floor installation, the thickness of the slab, which varies from 6 to 24 mm, is the most important parameter affecting the reliability and durability of the coating. The greater the thickness, the higher the load that the OSB board can withstand. But, as this indicator increases, the height of the room will also decrease, so it is important to balance the strength and elevation of the floor. In addition to the above, as this slab size increases, the cost of repairs increases.

Many years of application experience and calculations show that for installation as subfloors on lathing, it is necessary to choose the thickest sheets that are available in production - 22-24 mm.

When directly attached to screed or concrete, everything depends on the condition of the cement surface. If it is without significant irregularities and defects, then 10 mm panels are sufficient, but otherwise, the acceptable thickness of the slabs increases to 18 millimeters.

When the OSV surface is conceived as the front surface, 22 mm sheets will be needed. Since they will better thermal insulation and slightly deform under load, which will allow the paint finish to remain monolithic and durable. This information is presented more clearly in the table below.

Conditions for work	Recommended minimum thickness OSB sheets in millimeters
	OSB subfloor (covered with a layer of decorative material, for example – laminate)	Front covering (simply varnished or painted)
Lathing made of beams or logs	22	24
Plank surface with finishing sanding	18	22
Wave-shaped plank covering	22	24
Old concrete screed with significant defects	18	22
The surface is filled with self-leveling mixture, factory-made concrete slab with a smooth surface	10	22

The structural data of the material is also important. The board used is quality OSB-3, no less. Joints can be straight or grooved. In the latter version, the joints will be further strengthened.

How to lay OSB sheets on the floor

The technology for installing OSB panels on a horizontal surface is quite simple to implement and even a non-professional can handle it. The basic principle when laying floors from any material is to create a durable, even surface. When repairing floors with using OSB boards most often use three options for laying them:

• direct fastening to cement-concrete screed;
• on the floor made of old wooden boards;
• installation using lathing made of wooden logs.

All three possible ways have some nuances that should be taken into account during work.

Laying OSB on a floor with a concrete surface

The method is widely used in apartments of multi-storey buildings - where the base will not absorb dampness and excess moisture. This will keep the wood-shaving structure in its original form for a long time. The purpose of this method is to create a perfectly flat surface under decorative cladding and insulation of stone slabs.

The cement-concrete screed must be perfectly leveled before work begins. Residual roughness, cracks and local potholes are acceptable.

The process of laying OSB sheets on a concrete floor is performed in the following sequence:

1. The first step is to clean the work area well. You can use a regular vacuum cleaner for this. The sheets will sit on the glue and the dust-free surface will give a high degree of adhesion.
2. Afterwards, the cleaned base should be coated with a primer composition. This will help the glue adhere better. In addition, the priming process creates a fairly dense film that will prevent the screed from becoming dusty during use.
3. Then, they begin to lay OSB on the floor. If necessary, the slabs are cut. It is more convenient to do this using a cutting or circular saw.
4. The back side of the board is impregnated with a moisture-repellent primer with antiseptic properties and dried.
5. An adhesive composition is applied to the treated surface. It should be chosen only based on rubber. To distribute the mixture evenly, it is convenient to use a notched trowel.
6. Additionally, the panels must be secured with concrete dowels. This is done to guarantee and safe operation. It is best to drive the dowels along the entire contour of the slab. The distance from the edge should be maintained at 5 cm, and the interval should be 20-30 cm. With perfectly aligned and strong screed– it is enough to fasten only in the corners, but this takes into account the fact that a good adhesive is used.
7. Compensator gaps are left between adjacent sheets. Their width should be about 3 mm. There is also a 12 mm gap around the entire perimeter of the room. Subsequently, they will prevent deformation of the floor surface.
8. Finally cleaned thoroughly new surface. The joints are filled polyurethane foam or putty if you are going to apply paint or varnish later. After this, the floor should rest and dry. The foam is cut off, the putty is sanded and cladding can begin.

Adding an insulating substrate between OSB and concrete is undesirable - such actions lead to displacement and deformation of the floors subsequently. The sheets must adhere firmly, with their entire surface, to the base. Moreover, high-quality rubber glue itself plays the role of an insulating, water-repellent and shock-absorbing substrate.

Covering wooden floors with OSB sheets

This method is widely used in old premises where it has been preserved in good condition. wooden floor. The boards must be intact, not eaten by fungus and mold, and securely reinforced. This method allows you to save on materials, is simple to implement and functional - the old floor will serve as a tolerable barrier to moisture, cold and noise.

The goals that are achieved when installing OSB on wooden boards are their leveling before decorative finishing in the future, creating a continuous, seamless surface and strengthening subfloors.

It is important to inspect the old plank flooring. Make sure the integrity of the waterproofing that should be laid under the floors. Replace decayed and rotten spans. Level the surface as much as possible.

1. All nails should first be deeply sunk into the board. For this, it is better to use a hammer and a steel bolt. Unevenness and poor condition must be removed electric plane, until a smooth polished surface is obtained.
2. Old floor and reverse side slabs worth covering protective layer antiseptic.
3. Lay a layer of vapor barrier membrane under the OSB to prevent condensation from appearing on the sheets and their premature aging. For convenience, the waterproofing is grabbed with silicone glue, or applied with a construction stapler.
4. Mark and cut OSB, as shown in the diagram, for laying in a diagonal order. This will help avoid the formation of distortions and installation defects. The edges of the sheets that will be adjacent to the walls should be trimmed.
5. The panels are secured with wood screws. Screw in long hardware (TN 45 or more) in rows that will fall in the middle of the underlying boards. To avoid splitting the wood along the grain, lightly mix adjacent fastening elements in a checkerboard pattern. The distance from the edge of the OSB to the row of screws should be kept at 5 cm, the step in a row should be 30 cm, and the distance between adjacent rows should be approximately 40-65 cm.
6. The recesses for the screws are pre-countersinked to make them flush. This will protect subsequent finishing layers from perforation.
7. Expansion joints are filled with foam if the coating was intended as subfloors. When the OSB acts as the finishing surface, apply a layer of putty along the joints and holes for hardware.
8. The foam is cut off after final fixation, and the putty is leveled with a sanding machine.

Laying OSB on joists

Installation of a durable sheathing before laying OSB boards on the floor creates a hidden cavity for effective insulation, sound insulation and waterproofing, and tilt-adjustable logs allow you to level and prepare the horizontal plane for laying oriented strand panels.

Theoretically, the complete set of structural elements of such a floor consists of:

• load-bearing logs or beams;
• waterproofing bottom perforated membrane or film;
• top layer of vapor barrier (perforated membrane);
• insulation block - basalt wool or expanded polystyrene;
• reinforcing sheathing, which may not exist;
• OSB panels.

The technology for creating such complex design, is actually very easy to do and can be done by a non-professional. The main difficulty is the installation of a durable supporting frame.

Step one is installing the logs. Rectangular beams are used as load-bearing wooden or polymer elements. The most popular sizes for this purpose are 75x50 or 100x75. The size is selected individually, it depends on the length of the room, the pitch of the sheathing and the expected load. The main thing is that the insulation layer is flush with the beams.

Before installation begins, it is necessary to prepare the base for installing the logs. To do this, clean the entire surface from the possible presence of fungus and mold, which in the future may settle on wooden structures and destroy them. Treat the surface with an antiseptic and repair large defects in the concrete or wooden foundation. It is allowed to leave the maximum skew angle of the base at 2-3 degrees.

You need to decide on the direction of laying the lags. In the room it is required to place them perpendicular to the windows, and in walk-through corridors - across the movement of residents.

It is more convenient to maintain the distance between the rows of laid beams according to the dimensions of the insulating elements and a multiple of the dimensions of the OSB panels, which is about 40 centimeters. If you plan to use tiles, then the space is reduced to 30 centimeters.

You can begin installing and securing the logs - level the two most distant beams on opposite sides of the room. Pull the threads between them. All remaining elements will be aligned along this plane.

On a reinforced concrete base, logs are fixed and adjusted in various ways: with self-tapping screws, anchors, metal corners, using a polymer structure. The most reliable and functional way is to attach it to an anchor. This scheme is durable and the bars can be easily adjusted in level using threads and locknuts.

Installation of cross braces.

TO wooden sheathing The logs are fastened with screws on wood or on metal corners, and their level is adjusted using substrates. At the very end of the work, transverse struts are installed; they are attached to the places where the edges of the OSB sheets are expected to fit.

The assembled frame is treated with a primer, and underground communication is carried out in the space between its elements. The finished structure is a reliable support (the average calculated withstand load is 5 tons per 1 m2). Now you can lay the next layers on it.

Step two is to create a vapor barrier. The main purpose of this material is to protect the insulation from condensation. The layer laid under the insulation will waterproof it from external moisture, and the layer on the room side is a vapor barrier.

There are a great variety of materials produced for this purpose: polyethylene film, folgoizol, antioxidant insulator, vapor-permeable membrane. When using budget sealed films, it will be necessary to create high-quality ventilation in the house, and the membranes must be installed correctly. The rough side should be directed outward from the insulation.

The rolls are spread overlapping and the joints are soldered construction hairdryer and roll it with a roller or glue it with bitumen tape for tightness.

Step three - laying insulation. The function performed by this element is clear from its name. For correct placement between the frame elements, the insulation must be cut with a small margin for future shrinkage, then the cold will not have paths between the joists in the insulating layer.

Three common materials are used as floor thermal insulation:

1. Mineral wool,
   1. advantages: environmentally friendly, easy to install, does not burn, reliably insulates the room from moisture;

• Disadvantages: afraid of moisture, not cheap, requires good waterproofing.
• Expanded polystyrene,
  • advantages: best insulator, not afraid of moisture, does not require waterproofing;

• disadvantages: expensive, fire hazard, requires good ventilation in the room, fixed with polyurethane foam.
• Expanded clay,
  • advantages: affordable, does not require laying an inner layer of a vapor barrier, absorbs excess moisture, non-toxic, non-flammable;
  • disadvantages: poor heat insulator.

After laying the insulation, another inner layer of waterproofing is added, provided that mineral wool was used.

Step four - laying OSB sheets. Installation should be carried out in the same way as attaching oriented strand panels to a wooden floor. First, the lower surface of the slabs must be primed, the sheets themselves must be cut and laid on the joists. The OSB elements should be oriented so that their long side lies across wooden frame. The main thing is that the edge of the board never sag; if this happens, then it is necessary to add a safety element to the sheathing.

You can see this process visually in the video:

Operation of OSB floors

The resulting wooden surface gives free rein for further imagination in the decorative finishing of floors. It must be covered with layers of traditional material that is used for laying on floors. The facing coating applied on top of the OSB panels will provide protection for the wood-chip structure.

You cannot install warm floors under OSB boards. High temperatures will promote intense evaporation of heated formaldehydes, which bind the fibers. This will make the indoor atmosphere toxic. At the same time, the good insulating properties of wood will prevent heat from entering the house, which will lead to wasted energy.

If you carefully follow the work technology, the OSB board will serve for a long time, the atmosphere in the house will remain healthy, and its climate cozy and comfortable.

Wood is the most popular material for flooring in most homes in the post-Soviet space. Methods for leveling old wooden floors may be required for further installation of laminate or other flooring. This can be done in several ways.

Leveling a wooden floor with putty

A more radical way is to use logs for laying plywood sheets. To level a wooden floor with plywood, you need to align the logs in one plane. The plywood sheet itself is ultimately laid on a sheathing of 3 longitudinal joists and 3 transverse crossbars, the distance between which is 15-20 cm. This is the most popular method of leveling the floor with plywood.

It is customary to lay sheets of leveling material on top of the joists in a couple of layers, displacing their joints. There should be a gap of at least 2 cm between the wall and the plywood sheets. And between the sheets themselves, it is recommended to make compensation distances of 2-3 cm. This way the plywood will better tolerate high humidity and temperature changes will not occur when walking. Plywood sheets are attached to the joists and each other with self-tapping screws, which are installed in increments of 5-10 cm.

Additionally, it is recommended to use PVA glue between the plywood layers. The layers can be stacked on top of each other or offset technology can be used as in brickwork. When using the second option, work waste is minimal. After installation you only need to fill the gaps. As a result of this work, you will receive a perfectly flat floor, ready for laying any floor coverings.

Leveling a wooden floor with an OSB board

OSB boards are used in cases where, for some reason, it is impossible to do the same by pouring the mixture onto the floor. cement based. Giving a perfectly smooth surface using OSB boards - quick way leveling a wooden floor with your own hands. It will require:

• logs;
• OSB boards;
• screws or nails;
• dowels;
• jigsaw;
• a powerful drill, or better yet a hammer drill.

The logs are installed and secured with dowels to the floor. Wooden wedges can be used to adjust the installation height. They must be securely fastened. The logs are installed in such a way that on each one it is possible to fasten two edges of adjacent OSB boards. The joists must be 100% dry.

It is recommended to soak them in advance with wood solution. Do not forget that the base of the floor must be prepared accordingly - there are many means to protect it from the occurrence of mold or mildew. For example, a solution copper sulfate or primer mixture.

The resulting voids between the slabs and the floor can be filled with foam or expanded clay. The second option is better: expanded clay - more environmentally friendly material, and rodents won’t be able to do anything with it. OSB installation The slabs are made by screwing them to the joists using wood screws.

It is important to avoid cross-shaped joints between the slabs. The gaps between them should be 2-3 mm, and the distance from the walls should be about 15 mm. Thus, the slabs do not deform under the influence of humidity and temperature changes. Any type of base can be laid on a finished OSB base. flooring material. Only ceramics and finishes for which cement or liquid mortars are used are excluded.

From the author: We welcome everyone who reads this article! We dedicate today's material to those who want to independently update the flooring in an apartment or private house, spending a minimum amount of time. One of the most economical options- do-it-yourself OSB flooring. Its installation does not take much time, and the price allows you to purchase this building material without compromising your budget. We will tell you further about how to choose the material and carry out the repair correctly.

Characteristics of OSB boards

Before laying OSB boards, let's look at the features of this building material. Oriented strand boards are made on the basis wood shavings, consist of several layers, pressed together and glued together using various waterproof resins and synthetic wax. Under the influence of high temperature and appropriate pressure, a reliable, durable material is obtained.

Each slab usually consists of three (rarely four) layers. In external ones, shavings 7–15 centimeters long and 1–1.2 centimeters wide are located longitudinally, in internal ones - transversely. This solution gives special properties ready-made slabs. The material is classified according to the degree of strength, the index is indicated in numbers.

Source: http://pamir.mk.ua

Types of oriented strand boards

In construction, to make, the following types of slabs are used:

• OSB 2 - they are characterized by low moisture resistance. Can only be used when interior works ah in a dry room;
• OSB 3 - recognized as a universal material that is used for interior and exterior decoration;
• OSB 4 is the most durable and moisture resistant. Optimal for carrying out work on load-bearing structures under conditions of high humidity.

Advantages and disadvantages of the material

To know whether it is possible to use oriented strand boards for a rough coating and lay them as a finishing coating, let's look at the main qualities of OSB boards. Builders include the following among their advantages:

• environmental friendliness - natural wood is used to create this building material;
• resistance to temperature fluctuations and mechanical stress;
• high levels of strength, flexibility, elasticity;
• ease of processing and installation;
• uniform texture, which helps to avoid crumbling and delamination;
• Having made a subfloor, you can get a flat surface suitable for laying any finishing coating;
• due to their multi-layer nature, the slabs perfectly absorb noise, insulate and waterproof the room;
• the material is attractive appearance, at an affordable price.

The only disadvantage that is mentioned is that the resins may contain phenol, however, manufacturers today are successfully introducing new technologies that make it possible to create polymer resins without formaldehyde. Such products are labeled as “ECO” or “Green”.

Source: http://superdom.ua

Selecting OSB boards for installation

Let's find out how to choose slabs and other types of coatings. First of all, you should pay attention to the country of origin. The best material is considered to be produced in Europe and other countries North America, where the requirements are met environmental safety and new technologies are applied. Next, you should choose the right degree of strength of the slab. Experts agree that products with the OSB index 3 are optimal for residential premises - durable, reliable, and moisture-resistant. It is also necessary to take into account the thickness - if you want to lay OSB on, a 10 mm slab will be enough; if an option such as laying on wooden logs is used, the recommended thickness of the material is from 15 to 25 mm.

Preparing tools for work

Before laying OSB on an old wooden floor or concrete screed, you will need to stock up on the following tools:

• hammer;
• jigsaw;
• tape measure;
• hammer drill;
• screwdriver;
• level gauge;
• dowels and wood screws.

You also need to make sure that you have the necessary supplies on hand:

• OSB boards;
• baseboards;
• material for insulation (foam plastic, penoplex, mineral wool, etc.);
• wooden blocks;
• polyurethane foam;
• dry glue mixture for insulation;
• floor varnish.

Now you can begin work on laying the flooring.

Work order

To properly lay the material on a wooden or concrete base, you need to know how to perform each stage of the work. Our step-by-step instructions will help you with this:

1. If the concrete screed is smooth, without obvious defects, installation is carried out directly on it. Use one layer of slabs, follow the following sequence of actions:
   • clean the floor surface as much as possible from debris and dust;
   • cover the concrete screed with a primer for better adhesion of the glue to the base;
   • Apply special parquet adhesive to the OSB sheet using a notched trowel;
   • the tiles are laid on the floor and pressed;
   • leave between the mounted slabs expansion joints at least 3 mm, since under the influence of moisture the material can change size;
   • Drill holes in the corners of each OSB sheet with a puncher;
   • using dowels and self-tapping screws, secure the slabs to the concrete surface;
   • fill expansion joints with polyurethane foam;
   • The OSB floor is almost ready. All that remains is to let it dry for 4 hours, then you can cut off the excess foam, clear the surface of debris - and you can begin installing the finishing coating.
2. In the case when you need to lay OSB sheets on wooden floors, the work must be performed in the following sequence:
   • clean the surface as much as possible from debris;
   • inspect the old boards; if there are nails, push them deep into the floorboards. If necessary, treat the floor surface with a planer;
   • Place the slabs pre-cut with a hacksaw or jigsaw on the surface, not forgetting the need to leave 3 millimeters gaps between them;
   • to secure OSB sheets use self-tapping screws 4 centimeters long, keeping an interval between them of 20–30 centimeters;
   • recess the heads of the screws inside the slabs;
   • Carefully sand the joints between the sheets with a sanding machine.

That's all for today. We look forward to your feedback on how useful this information was. Subscribe to our groups on social networks, share links with friends - perhaps this material will help them make their home more comfortable and warm. See you soon!

OSB or OSB (oriented strand board) is relatively new construction material, which has become a successful alternative to plywood and chipboard. The role of OSB is great in frame construction, when insulating standard houses. Especially often, OSB is used to form and level floor surfaces. Today we’ll talk about how to do this correctly.

Types of OSB boards and their characteristics

OSB is a board consisting of several layers of wood chips pressed and glued with waterproof resins. Its gluing is carried out in 3 layers. In the outer layers, the chips are laid along the length of the panel, and inside - perpendicularly. This arrangement gives OSB strength and allows fasteners to be firmly held.

Used in construction the following types OSB:

• OSB-2 – panels with low moisture resistance. They are used only for interior work in dry rooms.
• OSB-3 – universal material. Withstands high humidity both indoors and outdoors. A large margin of safety allows it to be widely used in construction.
• OSB-4 is the most durable and moisture-resistant board. They are used to form load-bearing structures in conditions of high humidity.

For construction and leveling of floors, OSB-3 sheets are usually used, which can easily withstand the load from furniture, equipment, and people’s movement.

When leveling small floor defects, it is enough to use OSB boards 10 mm thick. Surfaces with significant bumps and potholes will require 10-15 mm of material. If you are going to create a floor on logs, then the thickness of the OSB boards used should be at least 15-25 mm.

For laying subfloors under finishing coat widely used wood boards, such as plywood and OSB. Let's compare these two materials in the following article: .

OSB boards are used as a flat and solid foundation for various modern coatings- parquet, tiles, linoleum, laminate, carpet. The main functions of oriented strand boards are:

• Creating a floor surface. OSB is a popular material for creating subfloors on joists. In this case, the flooring of the slabs can be carried out both on the upper side of the joists and on the lower side.
• Leveling the surface. Installing OSB on a wooden or concrete floor will help create a completely flat surface suitable for laying finishing coatings.
• Thermal insulation of the floor. OSB board consists of 90% natural wood chips, which have high thermal insulation properties. Accordingly, an OSB floor does not allow heat to escape and retains it in the room.
• Noise insulation. The multilayer dense OSB structure reliably absorbs any type of noise.

Let's look at a few popular technologies laying OSB on different substrates.

Installation of OSB boards on a concrete floor (cement screed)

Let's start with the simplest situation - leveling a concrete base with OSB slabs. The work is carried out according to this scheme.

Sweep away debris from the concrete base and remove dust with a vacuum cleaner. The surface must be absolutely clean to ensure adhesion of the mounting adhesive. The base is coated with a primer. This also promotes better adhesion of the glue to the base. In addition, the primer creates a dense film on the surface, which does not allow the screed to “dust” during use.

OSB is laid out on the surface, if necessary, trimming is done with a jigsaw or circular saw. Rubber-based parquet adhesive is applied to the underside of OSB, using a notched trowel to ensure uniform application. Glue the sheets to the concrete base.

Additionally, OSB is fixed with driven dowels. To guarantee retention, dowels are driven in around the perimeter every 20-30 cm. If the floor is flat and installation is carried out in a dry living room, then it is enough to secure the dowels in the corners of each slab (subject to the mandatory use of high-quality glue!).

When laying, expansion joints 3 mm thick are left between the slabs. Along the perimeter of the room, between the OSB and the wall, the seam should be 12 mm. These gaps are necessary to compensate for temperature and humidity expansion (swelling) of the OSB during operation.

On last stage work, the OSB base is cleaned of dust and debris. The seams between the wall and the slabs are filled with polyurethane foam. Its drying time is 3-4 hours. Excess dry foam that protrudes beyond the surface is cut off with a sharp knife.

Installation of OSB boards on plank flooring

Laying OSB on an old wooden floor helps level the surface and prepare it for installation of the finishing coating. Installation is carried out as follows:

1. To begin with, using a level or a rule, determine the localization of irregularities (bulges, depressions) of the boardwalk.
2. Boards that “walk” or rise too high above the general level are pulled to the joists with dowels, recessing them into the material. In some cases, to eliminate creaking and unsteadiness of the boards, the floor has to be rebuilt and the joists replaced (repaired).
3. Remove paint deposits from the flooring, erase swellings and protrusions with a sander or emery cloth.
4. OSB boards are laid out on the floor, with the seams of each next row offset. There should be no cross-shaped joints! Expansion gaps are provided (between the plates - 3 mm, along the perimeter of the walls - 12 mm).
5. Holes are drilled in the slabs. Their diameter should match the thread diameter of the wood screws that were chosen to fix the OSB to the floor. Holes are drilled along the perimeter of the slabs every 20-30 cm, and countersinking is performed for the screw heads.
6. Use wood screws to attach the OSB to the floor. The recommended length of screws is at least 45 mm.
7. If you want to make the floor more durable, install a second layer of OSB. The seams of the overlying and underlying layers should be laid with an offset of 20-30 cm.
8. Deformation gaps near the walls are filled with polyurethane foam, which is cut off after drying.

This completes the process.

Laying OSB on joists on a concrete base

If there is a concrete base (for example, a floor slab), installing joists and covering them with OSB sheets allows you to create a flat floor without the use of wet leveling screeds. And also incorporate insulating, moisture- and noise-insulating materials into the structure.

Let's consider the technology of creating an OSB floor on logs on an existing concrete base. Logs (wooden blocks) are fixed to the concrete floor using dowels or anchors.

The wider the distance between the logs, the thicker the OSB boards used. If the pitch is 40 mm, then the minimum OSB thickness is 15-18 mm; if the pitch is 50 cm, the thickness is 18-22 mm; if 60 cm, the thickness is 22 mm or more.

Thanks to the lags between the OSB and concrete floor space is created. It can be put to good use by placing insulating material. For example, the floors of the first floors are often cold, so a thermal insulator can be laid between the joists: mineral wool, polystyrene foam, EPS, etc. If there is a wet basement under the ceiling, the floor structure is supplemented vapor barrier films or membranes.

OSB boards are laid across the joists. The seams between adjacent slabs (widthwise) should run strictly in the middle of the log. During installation, it is recommended to leave expansion gaps (3 mm between the slabs, 12 mm between the OSB and the wall)

The sheets are fixed to the joists with self-tapping screws or nails (spiral, ring). Spacing of fasteners: along the perimeter of the sheets – 15 mm, on intermediate (additional) supports – 30 mm. Nails (or self-tapping screws) fixing the boards around the perimeter are placed at a distance of at least 1 cm from the edge (so that the OSB does not crack). Fastening elements are selected so that their length is 2.5 times greater than the thickness of the plates used.

How to fasten OSB boards to joists in an ordinary city apartment, watch the video:

Creating a subfloor from OSB on joists

Laying OSB on wooden joists – the simplest way get a durable and reliable subfloor. This technology is especially appropriate with existing columnar, pile, pile-screw foundation. Work order:

1. Logs are installed on the foundation. The log pitch must correspond to the thickness of the OSB boards used (than more step, the greater the thickness).
2. Perform rough rolling of the floor. To do this, retaining bars are nailed along the joists, and OSB boards are laid and secured on them. The surface facing the ground is covered with waterproofing preparations, for example, bitumen mastic.
3. A layer of vapor barrier is laid on top of the OSB.
4. Stacked thermal insulation material, for example, polystyrene foam, boards mineral wool, ecowool, etc.
5. Cover the insulation with another OSB layer. Fastening is carried out in the same way as when laying OSB on logs on an existing concrete base (the technology is described in the previous paragraph).

At this point the work process is considered completed.

Processing OSB for different finishing coatings

A strong, hard and smooth surface makes OSB a universal base for everything. modern views finishing floor coverings. How to cover an OSB floor? Here are some popular solutions:

• Varnish or paint. In this case, OSB boards will act as finishing floors, which only require decorative finishing paint and varnish materials. No additional training OSB sheets do not require, just clean them from dust and apply 2-3 layers of varnish (paint).
• Roll materials - linoleum and carpet. When laying roll materials it is necessary to ensure that the joints between OSB boards were located flush with the rest of the surface. It is advisable to remove all irregularities using sanding paper. Compensation gaps should be filled with elastic sealant.
• Tile(ceramic, vinyl, quartz vinyl, rubber, etc.). In order for the tile to be held on the OSB base, it is necessary to ensure its immobility. To do this, logs are placed more often than required by the thickness of the sheets. The pitch between the fastening elements is also reduced. The tiles are glued to OSB using a special glue suitable for wooden surface and the tiles used.
• Laminate– a finishing coating that is fixed in a “floating” way, without rigidly fastening the lamellas. This coating is quite rigid, so there is no need to prepare OSB for it. Minor irregularities that may exist at the joints of the plates are leveled out by the substrate.

What exactly to choose is up to you.

Using OSB allows you to inexpensively and quickly level an existing wood or concrete floor. And if necessary, create it from scratch on logs. An OSB surface will not require expensive finishing, additional leveling, or coating with moisture-resistant compounds. This is an excellent choice for those who want to create a high-quality floor with minimal effort.

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