Technology for fastening osb boards to the floor. How to level OSB wooden and concrete floors yourself

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Have you ever wondered why the housing problem has long been solved in America? It’s simple, they build frame or panel prefabricated houses en masse, such buildings are cheap, and the time from “start to housewarming” is only two weeks. The housing problem in our cities was solved in a similar way when panel houses were built in the 60s. But in those days, the state was not involved in construction in the villages; no one used accelerated technologies to low-rise buildings. Nowadays everyone takes care of their housing independently, and therefore frame and panel houses have become so widespread.

By all operational characteristics frame houses fully meet the most modern requirements. Except one. On TV we are often shown the aftermath of a tornado in America, many wooden structures are scattered around, entire cities are wiped off the face of the earth. And all because most of their houses are of frame type; such houses cannot withstand hurricane gusts of wind. But don’t worry, we don’t have and won’t have a tornado, this drawback can be ignored.

Sheathing methods frame houses

What is a frame house? A frame is assembled from wooden beams, edged timber from pine and spruce is used, insulation is done, the internal and external surfaces of the walls are sheathed with various materials. For these purposes, plasterboard can be used, plywood, boards, plastic panels and OSB boards. We will focus on the last material (OSB boards). We'll tell you about the technology and you'll get some practical advice on how to do such work quickly and with minimal financial outlay.

Selection of slabs

We recommend working with 12mm thick boards, but you can use thicker or thinner ones. While we advise you to heed our advice: thinner ones are a concern for durability, thicker ones will cost you dearly.

The slabs must be dry; for long-term storage it is necessary to use a shed. Work should only be carried out in dry weather. The number of slabs is determined based on the total area of the building walls; calculations are not very difficult. However, it must be borne in mind that the amount of unproductive waste will always be at least 10%. The more complex the architectural characteristics of the house, the more waste there will be, keep this in mind when purchasing materials.

General cladding rules

There are many different options for finishing frame houses, both interior and facade walls. We will consider only one of these options - covering external facade walls with OSB boards. How you cover the interior does not make much of a difference.

Can be mounted in a vertical or horizontal position, leave a gap of 2÷3 mm between the plates. To facilitate the process of setting the gap, you can use a simple device. Find any plastic strip of similar thickness and use it as a template; after fixing the slab, the strip is removed and used when fixing the next slab.

The distance between the stops of the slab should be 40÷60 cm. This must be kept in mind during the construction of the frame; it is best to use mineral or glass wool as insulation. Fasten the slabs using spiral or ordinary nails, self-tapping screws and other hardware. The length is selected taking into account the thickness of the slab, but it should be borne in mind that the nail must enter the body of the beam to a depth of at least 40 mm. It is desirable that the caps of the fasteners have an increased diameter.

Nails should be driven in ≈ 30 cm from each other; in places where sheets join, nails should be driven in at a distance of ≈ 15 centimeters. The distance from the edge of the slab to the nail must be ≥ 1 cm.

Frame house cladding technology

Initial data - the foundation has already been completed, the lower lining row has been laid, vertical posts have been installed in the corners and perimeter of the frame house.

We recommend starting the installation of the first OSB sheet from the corner of the house. Secure it level to corner posts at home, immediately fasten the second sheet to the other side of the corner. While performing work, carefully check their position with a level. If you make a mistake of a few millimeters on the first sheet, then on the opposite corner your millimeters will turn into centimeters. It is very difficult to correct such an error. To fully guarantee the accuracy of covering walls with sheets, we advise you, as in many cases during construction work, to use strong ropes stretched along the walls. They will help you accurately maintain the parallelism of the sheet installation lines.

Carry out the fastening in a circle, leaving space for window and door openings. Do not forget that the sheet must be reinforced along the entire perimeter of the openings; in some cases, additional beams or special load-bearing racks will have to be installed for these purposes.
Upholstering a house with slabs from the corner significantly simplifies and speeds up the construction process - there is no need to install longitudinal jibs. In the future, these cuts still have to be removed - unnecessary waste of time and material. But you can’t do without temporary cross braces, otherwise the frame will be too unstable.
To make the process easier OSB fastenings() we recommend attaching a small block to the bottom trim at the junction of two large OSB sheets, after which you can fasten the sheet to the vertical posts with screws or nails. If you have problems with horizontality, on some sheets you can “sacrifice” the gap, make it a little larger or completely eliminate it. If this defect is on 3-4 sheets, then there is no need to be afraid of any deformation due to linear expansion of the OSB sheets.
Work in a circle from bottom to top.

Install studs for internal load-bearing walls only when at least three walls of the house frame have been assembled and covered.

Finishing of sheets can be done in any way. But we would advise you to additionally protect them with plastic panels or siding - this will significantly increase the service life of the entire building.

OSB sheets in frame house allow you to decorate the external walls of the house. On the outside, OSB sheets are covered with either a ventilated facade, such as siding or plaster.

What thickness of sheets should I use for outdoor work?

OSB sheets have an outer and an inner side. The outer side consists of coarser fibers and should be screwed outward.

What kind of membrane is used to cut off moisture?

Use a quality moisture barrier membrane. Better, one that is used under the roof

Groove for thermal expansion of sheets

Leave 3-5mm between sheets for expansion space

At what distance should you attach the screws?

How to cut a sheathing profile

Metal scissors

MASTERMAX 3-ECO membranes

material three-layer waterproofing superdiffusion membrane (PP fleece) MASTERMAX 3 ECO - Masterplast application vapor-permeable lining roofing film, secondary protection against moisture and snow, placed directly on the thermal insulation density, g/m2 115 g/m2 (±20g) vapor permeability (Sd), m 0.05 max. pace. application, °C +70

What is expensive waterproofing material used for?

Over time, every material ages. This also applies to waterproofing membranes. To maintain the waterproofness of the walls of a house made of light reinforced concrete at the proper level, you should use a high-quality moisture-proof membrane.

Required Tool

Screwdrivers
Self-tapping screws with press washer
Steam-waterproofing
waterproofing membrane
screws for metal

What it is

OSB (Orient Strand Board or OSB) is oriented strand board (OSB), in which each subsequent layer of chips is laid across the previous layer. After this, the layers are glued together with waterproof resins and placed under a press at high temperature. Types of OSB

OSB boards were created for use in the construction of low-rise wooden houses in the relatively warm and dry climate of the United States and Canada. This probably explains the fact that in the humid climate of Russia, mainly moisture-resistant sheets of the OSB-3 class are widely used. The classification of OSB is made based on their possible use in construction.

Depending on the production method, moisture resistance and strength, four types of OSB are distinguished.

OSB-1 - has a small mechanical strength and low moisture resistance.
OSB-2 - has high mechanical strength and low moisture resistance.
OSB-3 - has high strength and is resistant to moisture.
OSB-4 is a high-tech type, has increased strength and rigidity, and very high moisture resistance.

In addition, OSB is divided according to the type of coating into varnished and laminated, which are used for formwork. And also according to the degree of processing - polished and unpolished.

Imported OSBs are divided into European and North American, depending on the standard by which they were manufactured. The American standard is more stringent. This applies to requirements for strength, dimensional tolerances, and compliance with environmental standards. However, the water resistance of North American OSB is noticeably inferior to European ones.

Story

OSB was first manufactured in 1982 North America at one of the woodworking factories. In the USSR, the appearance of OSB dates back to 1986, when a plant for their production was opened in Belarus.

Production technology

For the manufacture of OSB, flat chips up to 180 mm long and 6 to 40 mm wide are used. The layers of chips are laid in such a way that the inner layer is laid across the sheet, and the outer layers are laid along the sheet. Typically, an OSB sheet consists of four layers, which achieves greater rigidity and reduces the ductility of the finished sheet. For increase protective properties sheet, synthetic wax and boric acid salt are added to the adhesive resin. After which, during the process of heat treatment at high temperatures and subsequent hot pressing, a finished sheet is obtained from the chips. Properties

The main properties of OSB sheets are strength, rigidity, low specific gravity, and ease of processing.

OSB meets all the requirements for wood boards, but at the same time has the quality characteristics of wood. At the same time, OSB, unlike wood and plywood, is not subject to rotting, delamination and warping. In addition, they are not hygroscopic and are not affected by insects.

Currently, thanks to a radical improvement in the quality of adhesive resins, it has been possible to establish environmentally friendly production clean sheets OSB.

Advantages of OSB boards

Obvious advantages include their resistance to moisture and increased strength, as well as their low specific gravity.
Processing OSB is not difficult at all. They are easy to drill, plan and saw.
The OSB sheet securely holds the fasteners. These indicators are more than twice as high as those of chipboard.
Application The use of OSB is due to their properties.
They are used for wall cladding, and with any types of external coverings.
Also, OSB is used to make a continuous sheathing for the roof, regardless of its type.
In addition, OSB is widely used for assembling subfloors and flooring, and is also used as supporting surfaces.
OSB sheets are used to make load-bearing structures in wooden housing construction, as well as removable formwork for concrete work.
High-quality packaging and sandwich panels are made from OSB.

OSB processing

OSB is processed in the same way as solid wood. In this case, it is advisable to use cutters, saws and drills with nozzles made of hard alloys. In this case, the feed speed should be slightly lower than that used for processing solid wood.
To avoid vibration during processing, the sheets should be secured.
OSB can be cut both on stationary machines and using hand tools.
It is advisable to secure the slabs during processing to reduce vibration.

Fastening OSB occurs, in general, in the same way as fastening solid wood products, with screws, nails and staples. To increase the strength of the connection, ring and spiral nails are used. Smooth nails are not recommended.

During installation load-bearing structures fasteners made of stainless materials should be used.

Since changes in humidity in OSB may cause changes in volumetric characteristics, safety gaps should be left between OSB sheets to protect them from deformation.

Features of the use of OSB, OSB

OSB board, according to technology, should be transported and stored in such a way as to avoid damage during installation. For storing Osb, it is most convenient to provide a closed storage room with good ventilation. It is also possible to store Osb under a canopy so that they are not exposed to the risk of exposure to precipitation. If it is impossible to store or lay Osb boards using the technology under a canopy, it is necessary to prepare a flat horizontal surface in the form of a platform for laying and ensure insulation from the ground. Wrap the pallet in film, cover it with a tarpaulin or otherwise protect it from moisture, while still allowing air access to the stove. Possible options for pallet protection and stacking technology are shown in the figures.

Osb floor installation technology

Osb with straight edges is connected using technology to the floor joists, observing a temperature gap of at least 3 mm around the slab. When installing an Osb floor between walls or in the case of “floating floors”, using the installation technology, you should leave a 12 mm gap between the Osb and the wall. The slabs must be laid on the floor with their main axis perpendicular to the joists. According to technology, the connection of short edges of Osb should always be on the joists. Long edges not laid on joists must have a tongue-and-groove profile and a suitable support or connecting bracket. If the room where the flooring work is being carried out does not have a roof, then during precipitation, drainage should be provided.

OSB or OSB (oriented strand board) is a relatively new building material that has become a successful alternative to plywood and chipboard. The role of OSB in frame construction and insulation of standard houses is great. 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.

The following types of OSB are used in construction:

OSB-2 – panels with low moisture resistance. They are used only for interior work in dry rooms.
OSB-3 is a 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.

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

Creating a floor surface. OSB popular material to create a subfloor 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 several popular technologies for 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.

At the last stage of 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 protruding 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:

To begin with, using a level or a rule, determine the localization of irregularities (bulges, depressions) of the boardwalk.
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).
Remove paint deposits from the flooring, erase swellings and protrusions with a grinder or emery cloth.
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).
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.
Use wood screws to attach the OSB to the floor. The recommended length of screws is at least 45 mm.
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.
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 level 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 logs, space is created between the OSB and the concrete floor. It can be put to good use by covering it with 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 with 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:

Logs are installed on the foundation. The lag pitch must correspond to the thickness of the OSB boards used (the larger the pitch, the greater the thickness).
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.
A layer of vapor barrier is laid on top of the OSB.
Lay thermal insulation material, for example, polystyrene foam, mineral wool slabs, ecowool, etc.
Cover the insulation with another layer of OSB. 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 all modern types of 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 finished floors, which will only require decorative finishing with paints and varnishes. OSB sheets do not require any additional preparation; it is enough to clean them from dust and apply 2-3 layers of varnish (paint).
Roll materials - linoleum and carpet. When laying rolled materials, it is necessary to ensure that the joints between OSB boards are 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 adhesive suitable for the 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 laying the laminate. 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 - great choice for those who want to create a high-quality floor with minimal effort.

Orientation of OSB boards OSB OSB Boards consist of three layers. The chips in separate layers are arranged crosswise. This structure provides a high level of:

Constancy of size;
Fracture resistance (flexural strength);
Shear strength within the slab.

Since the OSB board consists of three layers, it has a longitudinal and transverse axis. The longitudinal axis coincides with the predominant chip direction of the top layer. It is parallel to the direction of the inscriptions (markings) applied to the slab on the edge of the slab. On milled panels, the longitudinal axis is located perpendicular to the markings on the panel surface. The strength and modulus of elasticity of the slab when bending along the longitudinal axis is 2 times greater than that of the transverse axis. Therefore, during installation it is necessary to observe the correct orientation of the slab specified by the designer (especially in single-layer building structures).

2. Acclimatization of slabs and protection from water and humidity OSB OSB OSB

Acclimatization of slabs

Before installation at the construction site, according to the recommendation of http://cmknn.ru/osb-3-osb-3, it is necessary to acclimatize the slabs min. 48 hours to equalize their moisture content with the humidity environment at the place of application.

Approximate moisture content values for slabs:

Installation conditions.
Approximate moisture content of the material
Room with constant heating 6 - 9%.
Room with periodic heating 9 - 10%.
Room without heating 16-18%

OSB boards must be protected from water when stored and used. After installation, the outside of the building, on the walls and roof, must be covered with appropriate insulation to protect against adverse weather conditions. The edges of OSB 3 boards (especially on the edges) are exposed to high humidity and may swell moderately (in accordance with the norm). In this case, before installing the final elements (for example, asphalt shingles on the roof), it is necessary to sand the joints of the slabs evenly (to ensure a smooth surface).

To prevent damage to OSB boards, it is necessary to eliminate excessive moisture, which can be caused by:

Using excessively damp or wet materials;
Installation on non-dried objects constructed using “wet” processes;
Errors during insulation work (water flowing into the building, incorrect installation of a vapor barrier layer, etc.);
Insufficient protection from atmospheric conditions ( external walls and the roof must be protected with suitable insulation immediately after installation).

3. Cutting, milling, drilling OSB boards

The boards can be processed in the usual way used for processing solid wood. Best used cutting tool and drills with a cutting part made of hard alloys. The feed rate depends on the tool used. It is recommended to reduce the feed speed moderately compared to the feed speed used when processing solid wood. The slabs must be secured in such a way that the slabs do not vibrate during processing. It is allowed to cut slabs using hand-held power tools

4. Fastening the plates

Fastening rules:

The minimum diameter (section) of staples should be 1.5 mm with a length of 50 mm;
For OSB board, you can use nails as for solid wood, screws or staples.
When installing load-bearing structures, it is necessary to use connecting elements made of stainless materials (galvanized or of stainless steel).
Strengthening the connection strength can be achieved by using special nails; ring or spiral (the use of nails with a smooth shaft is not recommended.).
The length of the connecting elements must be at least 2.5 times the thickness of the attached slab, but in no case less than 50 mm; the distance from the connecting element to the edge of the slab must correspond to seven times the diameter of the connecting element (i.e., when using nails with a diameter of 3 mm - at least 20 mm);
the maximum distance between nails driven into the edge of the slab should not exceed 150 mm;
the maximum distance between nails driven in the middle of the slab should not exceed 300 mm; slabs with smooth edges are mounted on supports (ceiling frame, ceiling beam);
Fastening thin OSB boards must begin from the middle of their upper part and continue fastening evenly towards the sides and downwards (to prevent swelling and sagging of the board).

5. Dilation gaps (lat. dilatatio - expansion) OSB OSB OSB

When installing slabs as a supporting structure for “floating” floors, it is necessary to leave a gap of about 15 mm wide when joining them to the wall.
When installing slabs as wall cladding, it is necessary to leave a gap of about 10 mm wide when joining them to the foundation;
If the length of the surface on which the slabs are mounted exceeds 12 m, it is necessary to leave 25 mm wide expansion gaps between the slabs every 12 m.
Since volumetric changes can occur in the slabs (arising mainly due to changes in environmental humidity, which affects the material), it is necessary to leave expansion gaps between them to prevent waviness or other undesirable phenomena from occurring on the slabs. slabs with smooth edges - when joining, it is necessary to leave gaps between them of at least 3 mm wide. slabs with milled edges (“tongue and groove”).
During docking, dilatation gaps form on their own. Expansion gaps 3 mm wide must also be left when joining slabs with other structures, for example, with the frame of a window, door, etc.

6. Surface protection and application of paint and varnish to the OSB board

We recommend performing a so-called test painting, which can reveal the incompatibility of the paint with the substances contained in the slab. When painting, follow the instructions and rules developed by the paint manufacturers. For interior surfaces that will be painted, we recommend using sanded boards. To paint the surface of the slabs, you can use ordinary colorless or colored paints used for painting wood.

ATTENTION!!! - During painting or immediately after painting, particles of chips may protrude from the surface of the slabs, and when using water-based paints, partial swelling of wood chips may occur. Such phenomena are not grounds for complaint.

7. Application of OSB OSB OSB A1

A1 Roof detail with prefabricated covering
A2 Roof detail with prefabricated covering for wet environments
B1 Roof detail with asphalt covering
B2 Roof detail with asphalt coating for wet environments
C Detail of external load-bearing wall
D1 Detail of internal load-bearing wall
D2 Internal partition part
E1 Floor detail with a “light” floating floor
E2 Floor detail with a “heavy” floating floor

Basic principles of using OSB boards in wooden structures and buildings

When designing and manufacturing durable timber structures with a long service life, basic principles of wood protection must be followed. Without an appropriate solution to the components of the structure from the point of view of building heating engineering and checking the temperature and humidity inside the structure, the mechanical strength and stability of wooden structures, as well as their resistance to destructive effects, cannot be guaranteed biological factors. To ensure long service life and reliability of new wooden structures and buildings, it is necessary to analyze all designed structures from the point of view of possible diffusion and condensation of water vapor or the relationship between temperature and humidity, as well as the corresponding stable moisture content of wood for compliance with the requirements establishing the environmental parameters for the use of OSB boards .

The main difference is possible limitation the influence of water vapor penetrating through the structure follows from the method of analyzing the properties of the vapor-impermeable layer. Vapor-tight layer of a building structure, limiting the penetration of water vapor from the environment into the interior building structure, due to equalization of temperature and pressure of water vapor in the internal and external environment. During this process, as a result of a decrease in temperature below a certain value, condensation of water vapor may occur. The resulting condensation can have bad influence on the properties of the building structure or reduce its service life. Limiting the penetration of water vapor into a structure means limiting diffusion (penetration of water vapor caused by partial pressure) and moisture flow (penetration of water vapor caused by air flow). In the specialized literature you can find a classification of materials for a vapor-proof layer according to the equivalent diffusion thickness. The equivalent diffusion thickness Sd (m) determines the air gap, which offers water vapor the same resistance as the corresponding layer of the building structure.

Note: The value of Sd is not the value of the diffusion resistance of the structure layer, given in m/sec.-1). A significant increase in humidity in the outer layer compared to the calculated model at the site of damage to materials is caused by the spatial distribution of humidity and their unequal properties.

Differences in material properties can be caused by the following:

violation of technological discipline
poor-quality connection of certain types of materials and their contact with openings and surrounding structures
aging of connections

Humidity and OSB boards OSB-2

Load-bearing boards for use in dry environments (resistance to humidity 12%) OSB-3 Load-bearing boards for use in humid environments (resistance to humidity 24%) OSB boards are classified according to the standard as OSB-2 and OSB-3.

Humidity class 1

It is characterized by the moisture content in construction materials, which corresponds to a temperature of 20°C. and relative ambient humidity exceeding 65% for no more than a few weeks a year. Average stable humidity most conifers do not exceed 12%.

Humidity class 2

It is characterized by the moisture content in structural materials, which corresponds to a temperature of 20°C and a relative humidity of the surrounding air exceeding 85% for no more than several weeks a year. The average stable humidity of most conifers does not exceed 20%.

Humidity class 3

Characterized by climatic conditions that contribute to an increase in the humidity of materials compared to humidity class 2.

General recommended principles for creating ceiling and floor structures

9. Ceiling structures

OSB ceiling designs OSB OSB

Installation: Mount slabs with smooth edges on load-bearing beams with an expansion gap of 3 mm. To increase rigidity, slabs with tongue-and-groove edges must be glued with glue (for example, polyurethane). Install all slabs in such a way that their longitudinal axis is perpendicular to the beams.

Make sure that all edges perpendicular to the longitudinal axis lie on the beams. The width of the expansion gap around the perimeter of the walls must be at least 15 mm.
Fasteners: Nails 2.5 times the thickness of the slab, minimum 50mm, spiral or grooved if possible. Screws 2.5 times the thickness of the slab, minimum 45 mm. (screws with a minimum size of 4.2 x 45 mm are recommended). The maximum distance between nails is 150 mm at the joints of the slabs, 300 mm at the plane of the slab. Nails are driven in at a distance of at least 10 mm from the edge of the slab.
Humidity Under the wooden ceilings of the first floor, located above the base, waterproofing is laid directly on the base to protect against moisture (film). Protect during installation ceiling structures from possible exposure to rain. When the ceiling is open, holes must be made in it to allow water to drain.
Recommended max. center distance between posts: min. The recommended slab thickness is 15 mm. 18 mm. 22 mm. The center distance between the posts is 300 mm. 400 mm. 600 mm. 800 mm.

Note The center distances between the posts are approximate. Dimensions are determined taking into account the length of the slab and a certain exact value of the load on the slab.

10. Floor structures on load-bearing lathing

The installation principles are the same as in the case of ceiling installation. When installing slabs, first lay a soundproofing layer on the supporting beams (pillows) to absorb the sound of footsteps.

11. Floating floor designs

Constructions of "floating" OSB floors OSB OSB The floor structure consists of one OSB board (OSB, OSB), tongue-and-groove thickness. 18 - 22 mm or from two plates (recommended) thickness. 12 - 18 mm (min. 9 mm). The distribution surface of the floor may consist of a single OSB board, for floors that do not have high requirements for constant shape, or in cases where concentrated loads are not expected (in areas above the tongue-and-groove joint). In other cases, use a two- or multi-layer floor structure.

The slabs are laid on sound insulation to absorb the sound of footsteps (rigid mineral wool or polystyrene mats intended for use in floor structures).
Individual layers of slabs are laid in mutually perpendicular directions and connected by gluing along the surface or with screws.
When using screws, we recommend connecting the slabs in both directions or laying an intermediate layer between them (extruded microporous polyethylene or PSUL sealing tape) to prevent possible squeaking. OSB-2 and OSB-3 are manufactured as structural boards with the appropriate permitted tolerances. Therefore, they can be used as a base under a classic parquet floor.

12. General recommended principles for creating structures for external and internal load-bearing walls

OSB boards OSB OSPOSB OSB OSB Installation

OSB boards used for walls can be mounted vertically or horizontally.
When installing load-bearing walls, it is recommended to use slabs whose length corresponds to the height of the walls (to make it easier to determine the required dimensions and install the slabs).
When installing slabs horizontally, it is necessary to place strips of slabs or stiffeners under all joints and free edges.
The slabs can be equipped with a wooden frame structure on one or both sides.
The slabs can be mounted on the outer and inner sides of load-bearing walls.

Dilatation gaps

To prevent possible water absorption, the expansion gap between the frame and the concrete foundation must be at least 25 mm wide. Expansion gaps can be created by installing the entire wooden structure on wedge pads, and filling the entire gap under the supporting wooden frame cement mortar. If the frame is installed directly on the foundation, then it is necessary to provide it with chemical protection and raise the slabs above the foundation level to a height of at least 25 mm. An expansion gap of at least 3 mm wide must be left between the walls and around the perimeter of door and window openings.

Fasteners Nails with a length 2.5 times the thickness of the slab, minimum 50 mm, if possible with a spiral or groove. Screws 2.5 times the thickness of the slab, minimum 45 mm (screws of at least 4.2 x 45 mm are recommended).

Nails are driven in at a distance of at least 10 mm from the edge of the slab, in load-bearing walls - at a distance exceeding 7 times the diameter of the fastening material (at least 20 mm). The recommended thickness of slabs for cladding frame walls is at least 12 mm when racks are located every 400 - 625 mm.

Thermal and waterproofing of slabs

As additional heat and sound insulation, it is recommended to use mineral wool on the façade side. In this case, it is necessary to take into account the method of fastening this facade system. When using slabs for cladding walls on the outside, it is necessary to take into account the diffusion resistance of the slab to the penetration of water vapor. On the other hand, slabs mounted on the inside of the wall can serve as a structural element with diffusion resistance (provided that the joints of the slabs and structural elements are sealed with appropriate insulating tape). When using tongue-and-groove boards, the tape can be replaced by gluing the tongue in the groove with glue (PUR, PVA). Bottom edge joint wooden structure with the foundation must be covered with a protective waterproofing compound (for example, based on bitumen emulsions). Recommended max. center-to-center distance between individual fasteners (nails, screws) Plate thickness; 9 - 12 mm. 12 - 15 mm. 15 - 22 mm. At the edges of the slab; 100 mm. 125 mm. 150 mm. On the surface of the slab; 200 mm. 250 mm. 300 mm. For load-bearing walls, the center-to-center distance between fastening elements is determined by static calculation. 13.

Installation of slabs Before installing the slabs on the roof structure, it is necessary to check the location of the rafters in the axes, whether they have any curvature and distinctive dimensions. Rafters that are curved or have different dimensions negatively affect the properties and appearance roofs. The slabs are connected in such a way that the edges perpendicular to the longitudinal axis lie on supports (rafters, slats, etc.) along their entire length. Therefore, it is recommended to choose rafter locations in modules with a span length of 833 mm or 625 mm. In the case of a different or longer span length (> 833 mm), to improve the surface of the roof structure, it is necessary to choose an option with longitudinal lathing made of slats or boards 80 - 100 mm wide.

By using slats mounted with a pitch (in axes) of 417 or 625 mm, it is possible to reduce the thickness of the slab (depending on the load). Slabs with a smooth edge There must be a 3 mm wide expansion gap between the slabs. To level the roof surface and speed up the temperature equalization of the slabs, it is recommended to strengthen the longitudinal edges of the slabs using steel H-shaped brackets.

Slabs with a tongue-and-groove edge

To strengthen the roof structure and increase the diffusion resistance of the structural layer, glue the edges with glue (eg PUR, PVA). Fasteners Nails with a length 2.5 times the thickness of the slab, i.e. 50 - 75 mm, if possible with a spiral or groove, galvanized or stainless steel, with a diameter of at least 3 mm. Screws with a length 2.5 times the thickness of the slab, but not less than 45 mm (screws measuring at least 4.2 x 45 mm are recommended). Nails are driven in at a distance exceeding 7 times the diameter of the fastening material, but not less than 20 mm.

Environmental exposure (temperature and humidity)

The slabs are used in the roof structure as a material with diffusion resistance. In rooms with normal air humidity of 50% (residential and office premises, etc.) they can be used in structures without a vapor-proof film, provided that the expansion gaps of the slabs are sealed with appropriate insulating tape or by gluing tongue-and-groove joints.

Protection from environmental influences

Recommended max. center-to-center distance between individual posts and fastening elements: Center-to-center distance between rafters; 600 mm. 800 mm. 1000 mm. Min. recommended slab thickness; 12 mm. 15 mm. 18 mm. Recommended distance between fasteners on the plane of the slab and the edge of the slab; 150 mm. Roof slope 40° or more - 150 Roof slope 30° - 40° - 200 Roof slope

Note. Dimensions are determined based on the specified value of the static load on the slabs. Boards that have been exposed to water (eg rain) must be dried before installation and covering the roof. The slabs have a slippery smooth surface. Therefore, it is necessary to ensure the safety of installers while working on slabs mounted at an angle. When carrying out installation work on the roof, it is necessary to strictly observe the safety rules and sanitary and hygienic standards established for work at height.

14. General principles of storage and storage of OSB boards (OSB, OSB)

Storage of OSB (OSB, OSB)

For storing slabs, it is most convenient to provide a closed storage room with good ventilation.
It is also possible to store the slabs under a canopy so that they are not exposed to the risk of exposure to precipitation.
If it is impossible to store under a canopy, it is necessary to prepare a flat horizontal surface and provide insulation from the ground with a layer of film, and also wrap the pallet with film.

Storage of OSB OSB OSB Storage of OSB (OSB, OSB)

OSB boards (OSB, OSB) must be laid flat on a flat surface. OSB boards (OSB, OSB) should not come into contact with the ground to avoid possible contact with water. The ideal base is a plank or lattice pallet. In addition, OSB boards (OSB, OSB) can be carefully laid on wooden slats of the same thickness; the distance between the slats should not exceed 600 mm. Storage of OSB OSB OSB Improper stacking can lead to deformation and damage to OSB boards (OSB, OSB). When placing several packs one above the other, the wooden slats should be in the same vertical plane. OSB boards (OSB, OSB) with limited space can be laid on the edge. In this case, the slabs should not be in contact with the ground and should be supported by a special rack. OSB OSB OSB Protection OSB (OSB, OSB) The top of the packs must be covered with a protective panel to prevent mechanical damage.

If the slabs are located outdoors, they must be protected with a moisture-proof coating. Protection during transportation of OSB (OSB, OSB) During transportation, OSB boards must be protected from precipitation. Humidity OSB (OSB, OSB) Like others wood boards, OSB boards (OSB, OSB) are hygroscopic and their dimensions change in response to changes in humidity. A change in the amount of moisture in OSB boards (OSB, OSB) can lead to changes in the size of the boards, and this can cause problems during the operation of the boards. A 1% change in moisture content generally increases or decreases the length, width and thickness of different grades of OSB boards (OSB, OSB).

What is OSB, their advantages and disadvantages, types of oriented strand boards and rules for their selection, technology for installing panels on joists and a concrete base, features of decorative finishing.

Pros and cons of flooring made from OSB panels

Every year the demand for OSB boards is growing, which is not surprising, because the material has the following advantages:

High level of panel strength. It is achieved due to the fact that in different layers of the board the chips are located perpendicularly. With the correct choice of tile thickness, the structure can withstand large force loads.
Light weight of panels. The standard weight of a whole board is no more than 20 kilograms. You can lift such material yourself; you do not have to hire a special team.
The structure is elastic and flexible, which allows you to bend the boards without fear of them breaking. This is very convenient if you want to make floors from OSB boards with a rounded or other shape, as well as when working with uneven surfaces.
The panels are characterized by a high degree of moisture resistance. This effect is achieved by treating the boards with resins. When compared with other wooden building materials, this board will deform less when in contact with water or moisture.
OSB is convenient and easy to work with. The panels can be installed using simple construction tools - a saw, drill and screwdriver. The cuts are smooth and require no additional processing. Various fasteners - nails and self-tapping screws - are well fixed on OSB. Installation of the slabs will not take much time.
The material has high thermal insulation performance. Since OSB boards contain more than 90% natural wood chips, they perform the function of floor insulation. Therefore, such a floor covering will not allow heat to quickly evaporate and will maintain a stable temperature in the room.
OSB provide good level soundproofing. The panels are multi-layered, thanks to which they absorb any noise well.
Resistance to chemicals due to resin treatment.
Particle boards are environmentally friendly. They are impregnated with special solutions that will prevent fungus or mold from forming on the boards.
OSB panels are budget and affordable.
OSB flooring perfectly levels the surface. The slabs can be installed on a wooden or concrete floor, creating an even coating on which the main finishing material can be laid on top.
They have a stylish wood-like color, so they do not require additional design processing.

The material does not have many disadvantages. Of these, the following can be noted: when cutting slabs, it is necessary to work in a mask or respirator, since wood shavings and dust are harmful to the respiratory system. Moreover, some types of low-quality panels can emit dangerous carcinogenic substances when working with them.

In addition, OSB subfloors may contain a synthetic substance such as phenol. But over the past few years, manufacturers have been actively solving this problem and switching to the production of formaldehyde-free panels. Such material is considered absolutely safe for human health. On its packaging you will find the “Eco” or “Green” label.

Main types of OSB for flooring

OSB is a panel consisting of three layers of wood chips, which are pressed and glued together in production using a waterproof resin. The direction of the chips inside the boards alternates: first along, then perpendicularly. Thanks to this arrangement, the plates are strong and hold the elements of the fastening system well.

Several types of OSB are used in construction work:

OSP-2. Such slabs have a low level of water resistance, so they are used only for interior decoration of dry rooms.
OSP-3. These are universal boards. They withstand high humidity both indoors and outdoors. The material is very dense, therefore it is used in construction work of any complexity.
OSB-4 panels. The most durable and moisture-resistant type of slabs. They are often used to create structures in rooms with high humidity levels.

Features of choosing OSB slabs for flooring

The most versatile material for finishing the floor in a residential area is OSB-3 board. It is recommended to choose products manufactured by Western European manufacturing companies. Such panels meet European quality standards and have high density.

The thickness of OSB boards for flooring can vary, but in order for the panels to retain heat well, perform soundproofing functions, and also level the surface, it is recommended to choose products eight to ten millimeters thick. When installing boards on joists, the recommended panel thickness is 16-19 mm. OSB-3 boards can withstand various power loads and people’s movements well.

To smooth out small defects flooring, it is enough to use material ten millimeters thick. If the floor has strong bumps and cracks, then slabs of 15-25 mm will be required.

OSB boards are often used for flooring under linoleum, parquet, tiles or laminate. This material serves as a high-quality and durable base for decorative coating.

Technology for installing OSB boards on logs

The choice of material and floor design depends on the purpose of the room and its characteristics. As a rule, two main types of laying OSB boards are used - on logs and directly on a concrete screed.

Advantages and disadvantages of fastening OSB panels to joists

This option for installing a subfloor is quite simple; you can do it yourself in a few days. OSB panels are dense, crumb-resistant, moisture-resistant, are not afraid of contact with biological and chemical substances and, most importantly, are perfectly attached to the bars.

Floors made from OSB slabs on joists are an excellent alternative to concrete screed. This installation allows you to save money on building materials. In addition, the surface can be easily insulated, and wiring communications will not cause problems - they can simply be placed in the cracks between the wooden blocks.

The advantages of laying OSB on logs include the fact that with their help, foundations are perfectly leveled even with the most sudden changes. The result is a smooth surface, and the floor structure is not weighted. If some panels become unusable, they can be easily replaced.

The only disadvantage of this installation method is that the entire structure turns out to be quite high, about 90-95 mm, and this will make the room lower.

Preparatory work before laying OSB on logs

The beginning of installation work is the preparation of the foundation. First of all, we inspect the floor for damage, cracks, chips, depressions, mold and mildew. If large defects are found, they should be removed before laying the logs. Minor imperfections can be left, since the height of the joists will hide them in any case.

Mold and mildew must be removed without fail. If this is not done, microorganisms will attack the logs, and over time, the OSB boards. This will lead to premature damage to the floor covering. All debris from the floor surface should be removed.

Logs can be installed on a sloping floor, but the maximum slope level should be 0.2%. To determine the angle, you must use a water level or a long level. If too large slopes are found, they should be leveled using a self-leveling mixture.

Procedure for installing floor joists

The dimensions of the beams for joists are always calculated based on individual measurements. In this case, the products must be of the same dimensions.

After they are prepared, we proceed to installation according to this scheme:

We install wooden beams along the entire perimeter of the room, fixing them at the same distance from each other - 40 centimeters.
The distance between the wall and the material should be no more than twenty centimeters.
We attach the logs to the base of the floor with bolts or self-tapping screws.
The upper surfaces of the logs must be in a strictly horizontal plane. Their evenness should be periodically checked with a building level.
If the room is sufficiently damp, the beams must be treated with protective agents against mold and mildew.
If necessary, we place insulation in the gaps.

How to attach OSB to joists

To lay OSB panels on the floor, you will need construction tools such as a tape measure, hammer, water level, jigsaw and hammer drill. Also, for the installation process, prepare special fastening systems for woodworking and a nail puller.

Oriented strand boards with plain edges should be laid on the floor. It would be good if there were grooves on them that would help fasten the panels together. To correctly calculate the required number of sheets, take into account the fact that seven percent of the material will be lost during cutting.

It is quite easy to install OSB floors yourself using the following instructions:

We lay the slabs across the joists.
The seams between the panels should be minimal and run clearly in the center of the joist. A distance of about two millimeters should be left between the OSB so that the floor does not deform over time and begin to creak.
We leave a larger gap between the OSB board and the wall - 12 millimeters.
We fix the panels to the beams using self-tapping screws or nails (ring, spiral).
The pitch of fasteners along the sheet should be about 15 millimeters. On additional supports - 30 millimeters.
We place the fasteners that hold the slab around the perimeter at a distance of about 1 centimeter from the edge. This is necessary so that it does not crack.
The length of screws or nails should be 2.5 times greater than the thickness of the slab.
The gaps formed between the walls and the rough floor covering must be filled using construction foam or mineral wool.

Thus, using OSB boards laid on logs, you can prepare a rough base for further laying parquet, tiles or carpet on it.

Laying OSB panels on a concrete screed

The procedure for installing OSB boards on a concrete floor is preceded by preparatory stage. Debris and dust must be removed from the base. For the glue to adhere well, the surface must be clean. Cover the base with primer. It will help the glue to better adhere to the panels, and will also prevent the screed from “dusting” during operation.

We lay the panels on the floor surface. If necessary, I trim the OSB using a jigsaw or saw.
Next, apply glue to the inside of the slab. To ensure that the product is evenly distributed over the surface, use a notched spatula.
We glue the particle boards onto the concrete base. Additionally, they can be secured using driven dowels, which should be placed every half a meter.
Between each slab we leave an expansion joint two millimeters thick.
The gap between the walls in the room and the wooden boards is no more than 13 mm. These seams are necessary to ensure that during operation of the coating, swelling does not form due to temperature and humidity changes.
The last stage of installing OSB boards on the floor is cleaning the panels from debris. We also seal all the resulting seams using polyurethane foam. It dries in three to four hours. Remove excess foam from the coating with a sharp knife.

Decorative finishing of floors made of OSB boards

After the installation of OSB boards on the floor is completely completed, you can begin finishing the floor covering. If you plan to leave such a floor as the main one, then, as an option, the surface can be completely covered with varnish or paint, and skirting boards can be installed around the perimeter.

No additional preparation of OSB for painting is necessary. You just need to clean the floor from dust and cover it with a couple of layers of varnish or paint. This can be done either with a roller or with a spray. Hard-to-reach places should be painted with a brush.

There are panels that cost more, but they are already available with a glossy sheen. Finishing such a covering will be very simple: you just need to decorate the perimeter of the room with a plinth - and that’s it, the floor is ready for use.

If you are laying rolled materials on top of the slabs, for example, carpet or linoleum, then make sure that all the joints between the OSB panels are flush with the entire surface and do not stick out anywhere. Any small irregularities can be removed using sanding paper. The expansion gaps must be filled with elastic sealant.

There is no need to prepare panels for laying laminate over OSB. Small irregularities at the joints will be leveled out by the substrate.

How to lay OSB on the floor - watch the video:

Installation of OSB boards is a way to inexpensively and efficiently level a concrete base. And if there is a need, then create a floor from scratch, securing the panels to the joists. This coating does not require expensive finishing or impregnation with moisture-resistant solutions, and you can even install it yourself.

The base for the floors can be made of oriented strand board - OSB. Such slabs consist of several layers of large wood chips glued together with resins, and in each layer the chips are oriented perpendicular to the previous one. As a result, high strength of the material is achieved.

Due to different compositions, processing methods, number of layers, and thickness of chips, quite diverse OSBs are obtained. It is important to choose the right type of OSB for certain conditions for creating floors, and also to correctly lay the slabs on the existing base. In turn, the installation method will depend on the surface or installation structure of the floor...

Classification of OSB, where they are used

There are several types of OSB based on moisture resistance and strength at the same time.

OSB-2 - used only inside buildings and only in dry rooms.
OSB-3 – can be used in wet areas and outside.
OSB-4 – characterized by increased strength, used for load-bearing structures, as well as in conditions of constant high humidity.

OSB-3 boards are most often used in construction. They are also better suited for creating a floor.

The thickness and grade of OSB is indicated in the design documentation.

When building at home, the following rules are usually used.
OSB-2 is used only where there are no variable loads, for cladding walls, interior partitions, furniture….

OSB-3 boards are used for flooring.

In this case, OSB-3 and OSB-4 boards with a thickness of 10 mm can be laid on flat bases.
If there are potholes larger than 5 cm, then slabs with a thickness of 15–20 mm can be used as a floor base.
The floor on the logs is created from OSB with a thickness of 15 - 30 mm, depending on the span.

A base made of oriented strand boards can be covered with any floor covering - laminate, parquet, planks, linoleum, carpet, PVC boards, as well as ceramic tiles, if the floor structure is sufficiently rigid and does not vibrate.

When deciding on the use of OSB, it is necessary to pay attention to the environmental friendliness of this batch. In Western countries, OSB is produced with very low emissions of harmful formaldehyde. Due to the release of vapors hazardous to humans, it is now not recommended to use well-known chipboard and some types of OSB in residential premises.

Due to the danger of formaldehyde release, the base made of OSB or OSB must be completely and very reliably fenced off by steam from the living space. Vapor barriers must be designed for such purposes.

How to level a concrete base using OSB

It is not a rare situation when there is a lumpy concrete base, but you need to get a flat surface. It won’t be difficult to lay OSB on your own.

If the slabs are fastened with tongue and groove, then it is possible to create a solid covering that does not need to be attached to the base. Separately laid slabs do not need to be secured to the base if the floor covering is not a rigid single structure and is not attached to subfloor. For example, under a laminate, particle boards do not need to be secured to the base, but under block parquet it is better to secure them.

Leveling a concrete base or cement-sand screed using OSB particle boards is performed in the following order. The surface is cleaned of dust and primed. Particle boards are prepared, cut to size, immediately for the entire base or for a significant part of the area. The plates are laid out and their position is verified.

Between the slabs are left expansion joints 3 mm thick. The offset of the seams in the rows is observed. From the walls to the OSB are left expansion joints 1 - 1.5 cm wide, into which polystyrene foam can be inserted.

Fastening OSB boards to the old floor

An old lumpy board base can also be leveled with OSB. There are no special differences in the work from a concrete base, only the fastening will be done with self-tapping screws in increments of 30 - 40 cm. To do this, holes are drilled in the OSB boards, and drilling is done for the screw heads.

It is important to properly prepare old wood floors for covering with slabs. Separately lumpy boards must be tightened to the joists with screws. Try to wedge loose and fastening floorboards from the underground side or tighten them with inclined screws... Irregularities, sagging old paint, can also be removed by sanding or shaving the boards.

Laying on joists

The distance between the lags is linked to the thickness of the OSB. It is recommended to make floors with a safety margin for vibration and deflection. Below are only the minimum values for the thickness of the particle board depending on the span between the joists:

400 mm – 18 mm
500 mm – 22 mm
600 mm – 25 mm

Usually the span between the lags is chosen to be 600 mm - according to standard width insulation, while the distance between the centers of the logs can be 75 cm with their own width of 15 cm. The floors will be durable if you use OSB with a thickness of 27 - 30 mm in this case.

The most common size of OSB sheets is 1250 x 2500 (mm).
The seams between the plates must be exactly in the center of the joists, leaving a gap of 3 mm between the sheets. The fastening step is 150 - 200 mm, the screw should not be closer than 1 cm to the edge of the slab. Holes are drilled for the screws and countersunk so that the heads are recessed.

The logs themselves can rest on a strip, columnar foundation, or a combination of both. Also, wooden logs can be laid continuously concrete floor and attached to it using anchors. The position of the lag is verified by level.

Application of insulation

The use of logs allows you to place insulation between them, and the following must be ensured.
The insulation layer is protected from the underground (concrete base) by a vapor barrier membrane. A ventilation gap of at least 2 cm in height must be left above the insulation. (The reverse placement is also possible - the insulation is left open at the bottom, laid on a solid wood flooring between the joists, and on top it is closed with a vapor barrier membrane, which is attached to the sides of the joists).

The appropriate foam thickness for a temperate climate zone, if the ventilated underground is insulated, is 12 cm, and if it is used mineral wool then this value will already be 15 cm. Above open passages, these values increase by 15%.

Oriented strand boards OSB can be laid without logs on a layer of extruded polystyrene foam, which in turn is laid on a leveled concrete base or on a wooden flooring. But in this case, you can only use OSB that is fastened with tongue and groove to each other, since the flooring will not be attached to the base. The evenness of the installation will depend only on the evenness of the base.

You can also lay OSB boards fastened together on top of a bulk layer of expanded clay. But this material should only be placed on a vapor barrier, as it perfectly accumulates moisture. The usual thickness of the expanded clay layer is 30 – 35 cm.

As you can see, leveling floors using OSB and creating OSB bases is not difficult at all.

To work with them you need at least a jigsaw, but for large volumes it is better to get a circular saw.

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 (pine, sometimes aspen). 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:

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.
OSB – 2. Such sheets can be used for arranging load-bearing structures only in dry rooms.
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.
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.

Table of characteristics of OSB-3 with different board thicknesses

Material thickness: 0.6-2.2 cm.
Environmental friendliness: according to laboratory studies of various 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 ranges from 420-780 rubles. a piece.

How to choose the right product?

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

Type of base. The thickness of the material depends on this.
Product size.
Necessary qualities (for example, if you are laying OSB in a dry room, then you may not need the quality of moisture resistance).
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. In this case, the seams in the lower and upper layers 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, an elastic sealant is used. 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 the 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 made 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.

Wooden floors in a private home lose their presentable appearance over time. Numerous layers of paint are cracking and peeling at the edges. And because of this, often even a newly painted surface looks sloppy. To tidy up such a floor, you have to completely clean the boards, treat the wood, and then periodically paint it again.

Therefore, when carrying out the next renovation, many homeowners make a different decision. Specifically: lay one of the modern decorative coverings on top of the wooden floor - laminate, parquet board, linoleum or carpet.

To implement such an idea, it is necessary that the base of the floor is suitable for laying a decorative covering. That is, it had a perfectly flat surface, aligned in a horizontal plane, without protrusions, “ladders,” or sagging areas. This can be achieved by installing OSB on a wooden floor.

Characteristics of OSB boards

General information about OSB boards

Unique physical and mechanical characteristics, at a relatively affordable price, make OSB boards increasingly popular in various fields of construction. With the help of this material, floors are perfectly leveled and laid, and with minimal effort, low cost and saving time. In addition, even a home owner inexperienced in the art of construction can handle the installation of slabs on the surface on his own.

Before studying the technology of installing OSB boards, it is necessary to briefly consider their characteristics and compare them with other similar materials.

It must be said that oriented strand boards, in some of their technical and operational characteristics, are superior to other materials of a similar purpose. But, due to their design features, they most often cannot be used as a floor finish.

Oriented strand boards are made from wood chips laid in several layers in a longitudinal-transverse manner. On the outer layers, chips are usually placed along the length of the slabs, and on the inner layers - across. The layers are bonded together under pressure with polymer resins.

Thanks to this technology for manufacturing OSB boards, they have improved physical and mechanical properties compared to some other similar building materials.

The main characteristics of oriented strand boards are shown in the table:

The characteristic features of OSB boards during their installation and operation can be outlined as follows:

High moisture resistance. When testing in laboratory conditions, the material was completely immersed in water for 24 hours. As a result, the swelling was only 18÷25%. And at the same time, the slab was not destroyed, and its strength was preserved.
Durability and long service life. Oriented strand boards can withstand high loads and extreme conditions. Thanks to the multilayer structure of the material, the plates hold fasteners well.
Easy installation of large-format sheet material.
The low cost makes such slabs affordable, even if the amount allocated for repairs is limited.
OSB boards, manufactured in accordance with technological requirements, consist of 96% natural materials. Therefore, they can be called conditionally environmentally friendly. If slabs are purchased for use in residential premises, you should choose material marked E1.

Thanks to your technical specifications oriented strand boards are excellent for subflooring under decorative flooring.

The slabs have a perfectly flat surface. Therefore, they can easily level wooden floors made from ordinary wooden board and deformed during long-term use.
Each slab covers a fairly large floor area. The most common sizes are 2240x1220 mm and 2500x1250 mm. And this corresponds to 2.98 and 3.125 square meters. When laying them, the surface will have a minimum number of joining seams. Therefore, they are ideal for arranging a base for flooring consisting of small-format elements - parquet boards, parquet, vinyl tiles, etc.

OSB boards have self-supporting ability and stable geometry. Therefore, they can be used as a subfloor covering, secured to frequently installed joists or sparsely left floorboards. Thanks to these same qualities, slabs can strengthen the old one, increasing its load-bearing capacity and rigidity.
Since the slabs consist of several layers of wood, which itself has sound and heat insulating qualities, covering them to some extent can protect the room from extraneous noise. In addition, an additional layer attached to the wooden floor will help reduce heat leakage from the rooms.

OSB boards are not afraid of moisture, so they can be used to create a subfloor structure on joists. Moreover, by sheathing the logs with them both above and below, it is possible to fill the resulting space with one of the insulating materials.

The table below, for greater clarity of information, shows the comparative evaluation characteristics of various slab materials, made from wood raw materials and having approximately the same purpose.

Name of the estimated parameters	Rating on a five-point scale
Final average score	2,86	3,00	3,28	3,57
	MDF	Chipboard	Glued plywood	Plates OSB
Strength	2	3	4	4
Resistance to external weather influences	1	2	3	3
Stability of dimensional parameters	2	3	3	3
Weight	2	2	3	3
Manufacturability of machining	3	4	4	5
Manufacturability of surface painting	5	3	3	2
Probability of material defects (delamination, presence of sinuses, knots)	5	4	3	5

Types of OSB boards

Today, construction stores offer several varieties of oriented strand boards. They differ in characteristics, and therefore in purpose. Therefore, when choosing a material for a specific area of construction or repair, it is necessary to pay attention to this factor.

OSB-1 - this material has very low moisture resistance and strength, and is not of particular quality. Therefore, such slabs are most often used only for auxiliary work.
OSB-2 boards are already of much higher quality, but their moisture resistance indicators are still not outstanding. They are, as a rule, intended for use in dry rooms in those structures where contact with moisture is completely excluded.

OSB-3 are universal products that can be used for covering surfaces both in dry rooms and in rooms with high humidity. They are used to cover walls, lay them on wooden floors when leveling them, and arrange floors along joists.
OSB-4 have a thickness of 15÷25 mm and are most often used for the construction of load-bearing structures in rooms with any level of humidity or even in outdoor conditions. They can also be used for flooring as a subfloor.

Plates can have different linear dimensions, but the most common are those dimensions that have already been mentioned above. However, you need to pay attention to this parameter when purchasing material. This way it will be possible to reduce waste when cutting them.

Preparing the surface for OSB boards

In order for OSB boards to fit perfectly on top of plank floors, and to avoid problems in the form of creaks and sagging during operation, a number of preparatory work must be performed before their installation:

An inspection of the plank base is carried out to identify rotten boards and joists. Creaking and warped areas of the old flooring are identified.
In addition, it is necessary to check the condition of the insulation, if it is present in the overall “pie” of the floor structure. Thermal insulation should not be damp, settled, damaged by rodents, etc. Sometimes you have to change it too.

You can check the evenness of a wooden floor using a building level or a rule. The tool is installed on the surface across the boards. If a gap has formed between the boards and the tool, then the floor is deformed and requires repair.

Unevenness in an old wooden floor is by no means uncommon. Over many years of operation, it is not only subjected to high loads, but is also “tested” by changes in humidity. A wet board becomes deformed when it dries - it can bend, wrap itself like a “propeller,” etc.

If the floors are not put in order, then the laid OSB boards will not rest on the entire plank surface, but only on the raised sections of the boards. And what will happen in the end?

During installation work, slabs with a small thickness will take the form of irregularities in the plank base. It will not be possible to properly lay laminate or parquet boards on such a surface due to the peculiarities of the interlocking joints.

Oriented strand boards of large thickness do not have pronounced flexibility, so it will not be possible to press them tightly to an uneven base using fasteners. This means that the coating will begin to creak either immediately after installation, or after some time.

There are two ways to level a plank floor:

Dismantling deformed boards and replacing them with new, smooth ones. The option can hardly be considered cost-effective, so it is used infrequently.

Surface scraping using special equipment.

The second option is possible if the boards have risen above the main surface to a not too great height.

If the boardwalk sags, it means that the board used is too thin. Or the logs underneath are spaced too far apart. If you use thin OSB boards to level such a floor, they will begin to sag along with the plank base. Well, the decorative coating will begin to “dance” along with them. In such situations, if the condition of the logs themselves does not cause any complaints, it is necessary to use OSB with a thickness of 18÷22 mm for covering the surface.

However, we repeat, this is only possible if the plank covering is mounted on strong, reliable joists. That is, they also need to be inspected by temporarily removing two or three floorboards.

If the floors were leveled using scraping, then upon completion of the work the boards must be thoroughly cleaned and then covered with a special impregnation with an antiseptic effect.

Installation work for laying OSB on a wooden floor

OSB boards are laid on wooden floors in different ways. This often depends on what kind of flooring will be laid on top.

For example, if you plan to lay laminate, parquet boards, vinyl tiles, etc., then the installation should be planned so that the joints of the flooring parts do not coincide with the joints of the OSB boards.
If you do not want to calculate the location of the floor covering elements, then you can choose the option of transverse laying. That is, lay the OSB slabs so that the joints of the finishing flooring elements are perpendicular to the joints of the base slabs.
Or, if you like, you can choose to lay the topcoat diagonally, at an angle of 45 degrees. By the way, such an installation scheme, for example, of a laminated board, can be relevant in rooms with uneven walls. This option will visually hide flaws in the geometry of the room.
Before starting installation, be sure to check the evenness of the corners. And it is advisable to start installation work with the smoothest of them.
Another frequently occurring problem is the divergence of opposite walls in the form of a trapezoid. In this case, it is necessary to make preliminary markings and adjust the slabs laid along the walls according to it. Leaving narrow wedge-shaped strips along the walls in the hope of later filling them with scraps is absolutely the wrong approach.

Installation tools

To perform installation work, naturally, you will need some tools and auxiliary materials:

To cut OSB boards, you must have a wood saw, an electric jigsaw and/or a hand-held circular saw on hand. A cut made with a regular hacksaw will not be very neat, and it will take much more time and effort. That's why best option- this is a jigsaw. Even a novice master can handle this tool. It is somewhat more difficult to work with a circular saw, but it is faster, and the cut is the most even.

If you don’t have such tools at your disposal, you can look for rental options. Many stores offer similar services.

To secure the slabs to a plank surface you will need
You will need a tape measure, a long metal ruler, a construction square, painter's cord for marking straight lines and a black marker.
Fasteners are black self-tapping screws 35 mm long.

There is a lot of controversy about black self-tapping screws, saying that they do not provide reliable fixation. It is difficult to agree with this - with a prepared, leveled, stable foundation, exorbitant loads are not expected. And such a self-tapping screw can break off only under very catastrophic destructive influences. But in such a situation, no other fasteners will help.

Installation of OSB boards

So, the installation process consists of several stages and is carried out in the following order:

The first step along the longitudinal wall of the room is to mark a line, which will immediately show how smooth it is.
The edge of the slab that will join the wall must be marked and trimmed so that it takes the direction of the wall and the shape of the corner in which it will be laid. The outer lines of the slab must remain perfectly smooth, with a factory edge. Therefore, it is not recommended to touch at least two sides of the sheet.
When laying the slab against the wall, it is necessary to maintain a deformation gap, which should be 10÷12 mm. To ensure that the gap is the same, you can use spacer wedges. Another option is to glue an elastic damper tape around the perimeter of the walls below before starting work.

All sheets of the first row may have to be adjusted along the line of the wall so that on the outside their edge forms one straight line. To make it easier to maintain this boundary, focusing on the outer edge of the first sheet, using a painting cord, beat out an even line on the plank floor from wall to wall.

All the slabs of the first row are laid along this line and then secured. It is necessary to leave a gap of 3÷5 mm between the plates to avoid squeaks or even deformations during thermal expansion of the material.

The second row of sheets, whatever their size, is laid so that their joints do not coincide with the joints of the sheets of the first row. That is, a displacement is made according to the “brickwork” type. It often happens that the remains of the last sheet of the previous row become the beginning of the next one.
The last row will also have to be adjusted, but to the opposite wall. Well, the very last sheet goes to the corner.

The slabs are fixed to the base using self-tapping screws. They are screwed in strictly vertically in increments of 350÷400 mm. And their caps should be recessed into the thickness of the slab by 2–3 mm. In order for the slabs to be fixed as firmly and reliably as possible, it is best to fasten them not only around the perimeter. As an option, draw two diagonal lines, and also screw in self-tapping screws along them with the same pitch. This is especially important if the base is covered with large, entire OSB sheets.

Some craftsmen use nails for fastening. But this is not recommended, since squeaks may occur during further use of the coating.

In fact, this is all the secrets of installing OSB boards on wooden base. As you can see, the task is not so difficult, and any owner should cope with it.

* * * * * * *

A few final words. Although oriented strand boards are considered suitable only for arranging a subfloor, some craftsmen can easily turn them into a decorative coating. For this process, special technology and varnish are used. At the same time, the floor surface is no less aesthetic and durable than when expensive materials are laid on it.

One more thing. You should never forget about your own health and that of your loved ones. Completely environmentally friendly OSB can be considered products of emission class E1 or E0.5 with the designations “Green” or “ECO”.

Such materials are made without components harmful to human health. As a rule, these are products from European manufacturers that fully comply with technology that meets strict EU environmental standards. However, the cost of such products is somewhat higher.

Some Russian manufacturers, unfortunately, do not care enough about consumer health. And most often, adhesives containing formaldehyde resins are used as a binder. The cost of such materials is low.

When purchasing OSB, each owner must decide for himself what is more important to him: the price of the material or the health of his family. And to make sure that the selected slabs are clean, you should ask the seller for a certificate of material quality.

The information content of the article will be complemented by a video that shows the nuances of installing OSB boards on a wooden base.

Video: Leveling a plank floor with OSB boards

Oriented strand boards (OSB) are a relatively new type of building material. They are often used as alternative option instead of chipboard and plywood when constructing flooring. Plates help get rid of various irregularities. This increases the strength of the floor. It's getting warmer. This base can be used for installation of almost any type of decorative coating.

Material advantages

The advantages of the material include:

it has high density;
moisture resistant;
the floor slab can be used to decorate an unheated room or bathhouse;
the surface does not crumble;
environmentally friendly;
natural wood chips are used in the production process;
easy to install;
has a low price;
using one element you can treat a large area of the floor;
able to withstand large deformation loads.

Classification of different types of slabs

Pressed wood chips are used in the production of the board. Waterproof resins are used for gluing it. The product consists of three layers. In the outer layers, chips are laid along the surface of the material. In the interior it is located perpendicularly.

There are 4 types of products:

OSB 1 is used in packaging production and in the manufacture of furniture blanks;
using OSB 2, internal rough work is carried out;
OSB 3 is a moisture-resistant material, used for interior and exterior decoration;
OSB 4 is a high-strength material used to form load-bearing structures.

The flooring is laid using OSB 3 sheets. They are able to withstand the required load and are resistant to temperature changes. They are easy to process and install. The material can be used as a base for laying linoleum, laminate and ceramic tiles.

Laying material on an old wooden surface

The plates are used to level the surface being treated. Laying OSB on a wooden floor is carried out in a certain sequence:

Uneven areas are located using a building level. Loose or raised floorboards must be pulled to the joists. For this, special dowels are used.
The paint is being removed from the floor. Sanding machine or use sandpaper to remove blisters.
Products are laid out on the floor surface. Cross joints must be avoided.
Gaps are left between adjacent panels. Their size should not exceed 3 mm.
Holes are drilled in the products. Their diameter must correspond to the diameter of the screws used. The holes are located along the perimeter of the panels at a distance of 30 cm.
Countersinking is performed for the screw heads.
By using fastening elements the panels are fixed.

The length of the screws should not be less than 45 mm. To make the flooring more durable, the OSB board is laid in 2 layers. The seam near the wall is filled with polyurethane foam. After it has completely dried, the excess is removed with a construction knife.

Creating a floor surface on a concrete base

Let's look at how to lay a coating on a floor with a concrete base. The boards contain natural wood chips. This structure of the material allows you to create high thermal insulation. In addition, the panels reliably isolate the room from the penetration of various noises.

Installation of OSB on a concrete floor is carried out as follows:

debris is removed from the concrete surface;
if necessary, it is further leveled;
a primer is applied to the concrete for better adhesion adhesive composition with base;
the panels are laid out on the surface to be treated;
glue with a rubber base is applied to the inside of the slabs;
sheets are glued to concrete;
the coating is additionally fixed using driven dowels;
There should be seams between the panels to compensate for deformation changes in the products;
at final finishing they are filled with polyurethane foam;
After drying, excess foam is removed using a sharp knife.

OSB sheets for wooden floors

Installing coating on joists

How to install panels correctly? Is it possible to do without using a leveling screed when laying slabs on a concrete base?

The technology for installing oriented strand panels allows work to be carried out in a similar way. In this case, wooden logs should be laid directly on the concrete surface. For fastening, special dowels or anchors are used. The installation step of the fasteners will depend on the thickness of the wood boards used.

Thermal insulation material is placed in the space created between the joists, the concrete floor and the top covering. If there is a damp basement below, vapor barrier films or membranes are additionally added to the structure.

When performing installation work, you must follow the following rules:

expansion joints must remain between the adjacent sheets;
the slabs are laid across wooden blocks;
self-tapping screws or special nails are used to fix wood panels;
the distance at which the fastening elements will be located should not be less than 15 mm;
their length should exceed the thickness of the panels used by 2.5 times.

Installation sequence

Installation of panels on logs is carried out in the following order:

logs are attached to the foundation or attached;
the fastening pitch depends on the thickness of the sheets used (it increases with increasing material thickness);
a rough roll is installed on the surface of the lag;
the main covering is laid on top and secured;
its internal surface is treated with waterproofing materials;
a vapor barrier layer and insulation are installed on the panel;
fits upper layer OSB on the floor.

Features of installation work

When performing installation work, you should use special clothing, gloves and safety glasses. The material itself has a fairly strong structure. But during the cutting and additional processing process, small chips and wood dust are formed, which can damage the eyes.

The panels must be laid and cut carefully, without using unnecessary force. Using the above instructions, you can easily lay the material yourself, without resorting to the services of professional builders.

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