OSB – 3, the technical characteristics of which comply with safety standards, can be applied in the internal space of residential premises. The class OSB – 3 assumes the possibility of using the material during external and internal works. At the same time, humidity can be moderate, which distinguishes canvases of this class from OSB – 1 and OSB – 2. The last two options have not so impressive density and do not undergo even a bit of high humidity.
OSB – 3 is based on wood chips. Canvases are obtained by pressing chips, when they are subjected to high pressure and high temperature. The adhesive base here is a waterproof resin. The plates consist of several layers, the chips in each of which are multi-oriented. OSB – 3 is a plate whose characteristics deserve attention - much stronger and more elastic than wood. The material is devoid of defects in the form of knots.
OSB – 3, whose characteristics are impressive, can be used in the construction of frame structures, as well as in the process of covering the wall framework system. Canvases are comfortable when leveling floors as well as floors. Builders found OSB is another use: in the construction of a constructive system of stairs and landings.
Leveling the floor with OSP – 3
OSB – 3, the characteristics of which allow the material to become more and more impressive, can also be used in leveling the floor. They are laid on a pre-mounted lag system. At the same time between the canvases at the moment of laying the temperature gap should remain, the minimum width of which is equal to 3 mm. Whereas between the slab and the wall, the width of this groove should be equivalent to 12 mm. The blades should be positioned, directing the main axis at an angle of 90 ° relative to the logs. Conjugation of short edges of the OSB should be located on the logs. Long edges that do not have an emphasis on the bars should have a tongue-and-groove lock, a brace, or some kind of support.
If the material is laid on logs installed on the ground, the soil should be well-insulated. Screws should be used to fasten the plates, which can be replaced with 51 mm spiral nails. Whereas if ring fasteners are used, its length should be equal to 45-75 mm. Installation of fasteners is carried out in increments of 30 cm. As for intermediate supports, fasteners are installed at the joints at a distance of 15 cm.
OSB – 3 - the plate, the characteristics of which will allow it to determine whether it should be purchased, can be glued to the surface of the lag, this will increase the rigidity of the system. It is recommended to use an installation adhesive made on the basis of chemical solvents. In the areas of locks, a crest-groove must be applied with glue of type D3.
Installing the OSP – 3 on the walls
OSB – 3, the characteristics of which allow installation on all types of surfaces, can also be used when leveling walls. Between the canvases, as well as around the openings, leave a gap, the minimum width of which is 3 mm. For wall cladding, professionals advise using an OSB that is 12 mm thick. If there is a need to make additional insulation of the system, then you can buy mineral wool, and on top of the plates to apply mineral plaster.
OSB – 3 plywood, whose characteristics attract home craftsmen and professional builders, is mounted on the wall using self-tapping screws or 51-mm nails. When installing fasteners, do not approach the edge of the sheet by more than 1 cm.
Installation of OSB on the roof
OSB – 3 plates, the technical characteristics of which make it possible to use them even when carrying out external work, should be fixed only after checking the flatness and strength of rafter legs or the lag of the batten system. If the above elements are not installed exactly enough, this will affect the appearance of the roof. When wet in the rain, it is not recommended to use them until it dries. When installing above the attic or any other space that is not heated in winter, you should take care about ventilation. Holes for this should not be less than 1/150 from the entire horizontal base.
Given the structure of the canvas, it must be fastened with a long edge at a right angle with respect to the rafter leg or elements of the batten. Conjugation of the short edges of the sheet should be on the backing of the roof. As for the long edges, they also need to hedge or connect with brackets, where necessary. Between the material with straight edges it is worth creating a gap, the minimum width of which is 3 mm: this will prevent deformation during expansion. The slab must be covered with at least two supports.
Installation in the presence of the chimney
At the time of fixing the material masters should remain on the roof beams or elements of the batten. If the roof system has an opening for the chimney, then the skin should be moved away from the chimney by a distance approved by building codes. In this case, you must also use screws or nails. Install fasteners should be at a distance of 30 cm, with screws on the rafter legs or components of the batten. As for the mating areas, the distance between the screws should be equal to 15 cm.
OSP – 3 2500х1250х9mm "Kalevala"
OSB – 3 2500х1250х9mm "Kalevala" plate, the characteristic of which will allow you to determine whether you should use it for your own needs, is a modern material. It is superior in its qualities to plywood and chipboard. The basis of the canvas is not only chips, but also technological resins. As a rule, OSB is made of aspen, as this breed is less exposed to the external environment. The cost of the canvas is 550 rubles. When mounting, it is worth counting that the weight of one sheet is equal to 17.3 kg. It is enough just to cut, cut, planed, and even grind if necessary.
You should not be afraid of the fact that the material will not hold the nails in itself, besides, the plates can be glued together with a joiner's composition, which will make it possible to obtain a sufficiently strong connection. If you intend to use the material outdoors, it is recommended to varnish it.
Covering the roof of OSB – 3, you will get a system that has excellent thermal and sound insulation qualities, which is very important for private buildings when it rains or when birds are excessively active. If you have a business in the production of upholstered furniture, then the described material will find its use there in the construction of buildings.
A fairly wide area of use has allowed OSP to gain popularity. This material is gradually replacing analogs, because its quality characteristics attract the attention of consumers.
Properties of plates and their characteristics
1. relatively high strength - about 2.5 times more than that of chipboard and MDF, but 2 times less than that of plywood,
2. low weight (depending on the size from 12 to 46 kg) - for the transportation of plates along the height, no special lifting equipment is required, the load on the roof, walls, foundation of the building is reduced,
3. relatively low cost (the price of the OSB of popular brands - in this review),
4. appearance, like that of natural wood, the surface is smooth, the color is uniform, the absence of voids and knots,
5. uniformity of technical characteristics, dimensional stability,
6. moisture resistance - oriented strand board does not lose its qualities after being in water for 24 hours,
7. ease of cutting and processing conventional tools (according to builders),
8. a relatively high retention rate of fasteners (25% more than chipboard or plywood), this property is due to the transverse orientation of chips in different layers of the sheet, nails can be hammered at a distance of 6 mm from the edge,
9. good thermal insulation and noise absorbing properties - better than natural wood and foam polymers (polystyrene foam), polystyrene foam,
11. resistance to vibration loads - due to its suitability for use in construction in seismologically active zones,
12. You can putty, paint, plaster, glue wallpaper or ceramic tiles, etc.,
13. Biological resistance, does not rot, is not a favorable environment for the development of fungi and mold.
- low vapor permeability - if it is of decisive importance in a particular case, then the problem is solved by frequent ventilation or a ventilation device,
- the probability of harm to health due to the release of formaldehyde and other toxic substances in a volume exceeding the maximum permissible concentration (maximum permissible concentration), but this indicator is better for OSB than for particle board, fiberboard and MDF because of the lower content of glue,
- narrow standard size range - this drawback does not matter much, as the products are easy to saw, and it is easy to assemble large items from the grooved items; it is possible to manufacture slabs of a non-standard size.
The disadvantages of RSD include relatively low fire resistance. They can not be used for construction and decoration of buildings with a high level of fire hazard. Some manufacturers impregnate the sheets with compounds that increase this indicator (flame retardants), but since the material is based on pressed wood, it will still burn after a while in a fire.
Fire resistance characteristics:
- flammability - B3 (highly flammable),
- smoke-forming ability - D3 (high),
- flammability - G4 (strong)
- toxicity of combustion products - G4 (extremely dangerous).
Varieties of surface finish and ends:
- lacquered - varnished on one side
- laminated - covered with laminate, is intended for reusable use (up to 10 cycles) as a formwork for pouring concrete,
- grooved - the ends have the shape of grooves-tongue locks for securely connecting the sheets to each other, in many cases additional mechanical fasteners are not required.
- OCP 1 - for use in low humidity conditions,
- OSB 2 - for bearing elements of building structures in dry rooms,
- OSB 3 - the same in rooms with high humidity,
- OSB 4 - for systems bearing significant loads in conditions of high humidity.
OSB3 and 4 are well tolerated by short-term exposure to moisture, due to which they are suitable for facade work, but are not designed for long or permanent stay in water.
Scope of use of plates:
- removable multiple formwork for concrete work,
- draft floor (dry screed) - logs and flooring for ceramic tiles, laminate, linoleum, carpet, parquet, solid and parquet boards,
- flooring for light buildings,
- wall cladding - combined with many types of exterior finish,
- roof lathing - withstands significant wind and snow loads, is used as a base for slate, flexible and concrete tiles, metal roofing, many other types of roofing materials,
- I-beams for wooden buildings
- wall leveling
- SIP panel,
- furniture production - for the manufacture of frames,
- construction of stairs, scaffolding,
- installation of temporary buildings
- assembly of boxes for transportation, shelving, exhibition stands, billboards.
OSB is not recommended to use:
- for decoration of children's rooms,
- in medical and child care facilities
- in the bathroom, shower, pool.
About the harmfulness of the plate
The danger to human health lies in the release of formaldehyde contained in adhesive resins and which, according to doctors, is not only toxic, but also carcinogenic. The same harm can be caused by any building materials from wood waste - particle board, fiberboard, MDF, laminate. They all contain adhesive components that release formaldehyde. In OSB, this indicator is the best, since less adhesive is required for its manufacture.
To minimize potential harm, it is recommended to purchase plates with a high emission class of hazardous substances - E 0 or E1. Materials of this quality comply with the requirements of safety standards for human health. When buying, you need to pay attention to the labeling. If the emission class is not specified or lower than recommended, it is better to choose products from another manufacturer.
It is advisable to purchase products of famous European or American companies. Most Russian factories are a little inferior to them in quality and safety, only a few have reached a similar level. The worst characteristics of harmfulness have Chinese sheets. They can only be used for finishing non-residential premises. Many large manufacturers produce OSB plates with the brand Eco or Green. The adhesive components used to manufacture them do not contain or have a minimum amount of harmful substances.
In the process of working with OSB, protective equipment such as goggles and a respirator are required during cutting and processing. Resins cause irritation of mucous membranes, allergic reactions, generally worsen health.
“He built the second floor, used birch boards and OSB 4. The material is excellent, stronger than drywall. Sheets with a thickness of 9 mm approached the outside of the wall paneling; 6mm plates took for the interior trim. The fasteners are perfectly supported (even the radiators are fixed). ”
Anton, Nizhny Novgorod.
“It was necessary to level the board floor in the old house, the choice fell on the oriented strand board. First of all, because of the price - it is almost two times cheaper than plywood. The new floor is three years old, there are no defects, everyone is happy. ”
“We needed building material for dry screed. Stumbled upon a grooved oriented strand board, the price pleased. The tongue-and-groove connection system helped to mount the subfloor very quickly, in just two days, finished the whole apartment. ”
“Made of OSB 3 (moisture resistant) floor in the kitchen. I laid linoleum on top of it, not sticking. Later it turned out that water leaked from one of the hoses of the washing machine and fell directly into the gap between the linoleum and the wall. As a result, the plate is still rotten. I admit that I am guilty, not the manufacturer. "
“On the poisoning of people with formaldehyde, released from the OSP. After reading the reviews, we bought Canadian plates of class E0. The quality is very high. The sheets are flat, smooth, the ends are processed with a green edge. Decorated the entire loggia (ceiling, walls, floor). Top covered with panels, the floor is laminate. They coped with the work quickly; there is no smell about them. ”
What is OSB?
Since the creation of the first OSB plate, the abbreviated name of which in Russian sounds like OSB (Oriented Strand Board) 30 years have passed. This material was developed in the era of mass construction of prefabricated frame houses. Today, millions of citizens of Canada, the United States and Europe live in them.
The wooden frame required light and durable sheeting, able to withstand the action of moisture and solar radiation. Traditional chipboard is not suitable for this. It is too heavy and is afraid of moisture. Natural wood for exterior decoration is suitable, but its installation is low-tech (takes a long time). The solution was found when, instead of indiscriminately mixing sawdust and shavings, the technology of oriented layering of long chips was applied. The adhesive for it was glue based on formaldehyde resins.
Wood chips treated with adhesive mixture are placed in the outer layers of OSB in the longitudinal direction, and in the inner layer - in the transverse. After that, it falls under a powerful thermal press. Here the process of polymerization (hardening) of the glue takes place and the plate turns into a solid wood conglomerate of minimum thickness and maximum strength.
Since the chips are laid in mutually perpendicular directions, the deformation of the OSB under the action of alternate soaking and drying is minimal. This fact is of paramount importance for high-quality cladding walls "skeleton" and crumb.
Summarizing all that has been said, the question of what is PCA can be answered briefly. This is glued and pressed wood chips.
Insulated CIP panels for prefabricated houses, the creation of which without OSB would be impossible, became the first stage in the use of new material. Today it can be found in almost all areas of the construction industry.
Specifications and applications
- OSB board density ranges from 640 to 700 kg / m3.
- Swelling ratiofrom 10 to 22% (tested by soaking with water for 24 hours).
- Flexural strength. According to the European standard EN 310, it is 20 and 10 Newton per 1 mm 2 (longitudinal and transverse bending, respectively).
- Mechanical holding capacity This material does not have an exact digital expression, but is estimated by experts as very high. Screws and nails such a plate holds securely.
- Paintability and adhesion. Plates well perceive paints and adhesives, which allows to vary their appearance over a wide range.
- Manufacturability. This material can be cut, cut, drill, nail and grind. The large area provides the plates with simple and quick installation.
- Fire safety. Плиты из ориентированной стружки относятся к группе горючести Г4. Это значит, что они весьма пожароопасны. Для снижения горючести до приемлемого в жилищном строительстве уровня (Г2-Г1) их обрабатывают огнезащитными составами.
Области, в которых нашла применение OSB плита, весьма многочисленны:
- обшивка стен каркасных домов,
- основание под кровельную битумную черепицу,
- подшивка потолков, основа для монтажа напольных покрытий,
- обшивка деревянных лестниц,
- formwork panel structures,
- racks and stands,
- fencing construction sites.
Types and sizes
There are several varieties of this material. The first level of differences belongs to the class of plates, denoted by the numbers from 1 to 4:
- OSB-1 - material of low strength class. Such plates can be used only in dry rooms in structures that do not bear the load (furniture, siding).
- OSB-2- it is allowed to use for the erection of supporting structures in dry rooms.
- OSB-3 designed to operate under load in high humidity conditions.
- OSB-4 designed for wet environments and intense mechanical stress.
The industry also produces special types of OSB - laminated. They can be put indoors, and also reused for formwork.
For the installation of floors using tongue-and-groove plates. At their ends, special notches and protrusions (grooves) are applied for a more tight connection.
Note that OSB-3 plates are the most widely used in construction. They have an acceptable cost, good installation and performance.
Manufacturers produce OSB boards of the following size range:
- (with smooth edges) 3125x2000 mm, 2800x1250 mm, 2500x1250 mm, 2440x1220 mm,
- (grooved edge) 2500x1250, 2450x590, 2440x590, 2440x1220 mm.
In retail, OSB plates with a size of 2.5x1.25 meters can most often be seen.
The thickness of this material is from 6 to 22 mm.
Advantages and disadvantages
In the category of advantages of OSB plates can be written:
- High moisture resistance.
- Low weight.
- High mechanical strength and stability of geometric characteristics.
- Easy installation.
- Aesthetically acceptable appearance.
Some authors attribute the low cost to the GSP. We will not agree with them, because a high-quality imported cooker, impeccable by sanitary standards, has a high price.
The disadvantages of this material include:
- Low bending strength.
- Low level of environmental safety of products of some domestic companies.
Harm to health
This is the most "painful" topic, around which there are constantly disputes. Plate manufacturers claim they are completely safe for health. Experts, on the contrary, are skeptical about their sanitary and hygienic properties.
Let's see what is the reason for such polar opinions. As we have said, the adhesive in formaldehyde acts as a binder in the plates. In a chemically bound state, it is safe. However, in the process of pressing the plates under the action of high temperature, the molecular chains of the glue break down and gaseous formaldehyde enters the atmosphere.
As you know, the line between poison and medicine is very thin. In low concentrations, poison is a medicine, and in large concentrations it causes serious harm. Something similar happens with formaldehyde. The degree of its toxicity depends on the number of molecules in the air.
There is a notion of emission level. It is used to standardize the sanitary and hygienic qualities of OSB, dividing them into three classes:
- E0 - emission from 3 to 5 mg / 100 grams of dry material,
- Е1 - emission of no more than 10 mg / 100 g.,
- E2 - formaldehyde emission is in the range from 10 to 30 mg / 100 g.
For indoor use, OSB E0 and E1 can be used. The material of class E2 is intended only for outdoor installation (roofing, wall cladding).
In the sanitary certificates issued to manufacturers of slabs, you will not see this classification. In them, the assessment of toxicity is based on the MPC (maximum permissible concentration). It is measured in milligrams of formaldehyde in 1 m3 of room air. The permissible concentration in this case is no more than 0.003 mg / m3.
After formaldehyde in the sanitary certificate is a long list of other toxic substances, the level of which requires checking GOST.
At the end of the list we see the final indicator, called the toxicity index in percent. In this case, it ranges from 70 to 120%. According to sanitary classification, this means that OSB is non-toxic.
In order to protect your home from formaldehyde emissions, we recommend taking the following steps:
- Do not buy a slab class below E1.
- If there are doubts about the quality of the material, then before installation it should be kept under an open shed for 3-4 months. During this period, the concentration of free formaldehyde will decrease several times.
- Interior finishes of low toxicity OSB must be treated with a detoxifying primer.
- The room lined with this material should be aired daily.
- During the summer period, it is not allowed to overheat the room above + 30С.
- Do not allow air humidity to increase above 70%.
Verified Manufacturers and Estimated Prices
Since it is not difficult for a manufacturer to get a “fake” certificate for a poor-quality domestic plate, we advise you to focus on products of proven brands when buying. This group includes the Egger, Glunz, Kronospan-Bolderaja, Kalevala trademarks.
Approximate prices for materials (end of 2015) produced by these well-known manufacturers are:
Kronospan-Bolderaja OSB-3 (emission class E1) size 2500 * 1250 mm - from 510 rubles / sheet (thickness 9 mm) to 1300 rubles / sheet (thickness 22 mm).
German plates Glunz and Egger of the same size and thickness are significantly more expensive - from 650 to 1800 rubles for 1 sheet.
The average price group is represented by Russian Kalevala OSB-3 plates. They can be purchased at a price almost identical to Kronoshpan from 530 rubles per sheet (9 mm) to 1,300 rubles per sheet (22 mm).
Finally, we traditionally note that material prices may vary significantly depending on the region, as well as on the volume of the purchased batch.
Oriented strand board OSP-3 (OSB-3)
Oriented strand board, eng. "Oriented strand board" - material compressed from three layers of oriented (directed) wood shavings. The orientation of chips in OSP-3 has a special meaning:
- internal the part has a transverse orientation
- external parts have a longitudinal orientation.
The production of plates is carried out by special chip machines, in which the wood is crushed (debarked), and then thoroughly dried in special installations.
The final stage of preparation is the sorting of chips and its rejection according to the characteristics. In the production of OSB, wood chips may have the following dimensions:
- in length up to 15 cm
- in width to 1.2 cm,
- in thickness to 0.08 cm
At the end of the production, the layers of chips are laid out in orientation along the conveyor of the machine in a certain plane, after which they are pressed and cut along the dimensional grid. At the output of such production, a material of a certain size is obtained, made of correctly oriented wood chips, glued together with resin hardened from high temperatures in the press and treated with chemicals to increase the resistance to weather conditions.
Oriented strand board according to generally accepted European standards is classified by type:
- low strength for use in rooms with low humidity - type OSB-1,
- high strength for use as a supporting structure in rooms with low humidity - type OSB-2,
- high strength for operation in high humidity conditions - type OSB-3,
- durable material for use as a supporting structure in high humidity conditions - type OSB-4.
Depending on the external coating, OSP-3 is divided into the following types:
- with additional surface treatment (polished),
- without additional surface treatment (unpolished),
- with finished ends (grooved),
- one-side varnished (varnished),
- covered with laminate (laminated).
The type of plate depends on the area of its application. The higher the density and strength of the plates, the higher the endurance under heavy loads in difficult conditions. This quality of OSB directly affects the cost of the material, since the higher the marking of the material, the higher the cost.
Modern production of building materials allows us to produce products with any technical characteristics.
OSP-3 has various formats:
- sizes can be: 1220 mm × 2440 mm, 1250 mm × 2500 mm, 1250 mm × 2800 mm, 2500 mm × 1850 mm,
- plate thickness may be: 6 mm, 8 mm, 9 mm, 11 mm, 12 mm, 15 mm, 18 mm, 22 mm.
Video: overview and material properties of the OSP OSB-3Weight depends on the size and thickness of the OSB and can vary from 15 kg to 45 kg.
OSB density - 650 kg / m2, which equates to the density of coniferous plywood.
The choice of oriented strand board is influenced by the scope of the future application of the material and the conditions for storage if necessary. Maximum storage characteristics help storage in a warehouse with moderate humidity and good ventilation.
In the absence of such conditions, storage under film or a shed is suitable, and it is important to isolate the plates from all sides with environmental protection from the film cover.
Oriented strand board in its characteristics has such positive qualities:
- the naturalness of raw materials in production determines the environmental friendliness of OSB,
- reasonable cost makes the material in demand,
- made of wood chips, so it has a small weight,
- OSB made from natural raw materials provides ease and convenience in work, so it does not require the use of highly professional tools,
- the transverse orientation of the wood chips gives the board flexibility, this quality is appreciated when working with rounded surfaces,
- transverse orientation also allows to withstand heavy loads in operation,
- wood chips have sound and heat insulation, giving such qualities and OSB.
In contrast to the mass of advantages, the flaws of the PCB have few The main reason for their presence depends on the manufacturer:
- A large amount of detachable wood dust when working with OSB requires the obligatory presence of protective equipment (goggles, mask, gloves). Moreover, a material that has been processed by the production of chemicals, getting into the bronchi and settling there, can cause allergic reactions or other complications in the functioning of the respiratory organs.
- For the production of low quality OSB, resins with phenol-formaldehyde components can be used, which, during the operation of the material, are capable of releasing carcinogens, poisoning indoor air.
Scope of oriented strand board is extensive. In the internal workings of OSB use:
- for leveling floors,
- wall cladding and ceilings
- construction of frame structures, including ladders and floors,
- in the manufacture of frame furniture or storage racks.
For external works, PCBs are used:
- as a roofing base for laying shingles, Use of OSB for laying shingles and covering the facade walls
The best manufacturers in Russia
Good characteristics and low cost of OSP-3 makes the material in demand, and its production are in many countries around the world. The only significant difference is the presence of high technologies and innovations in European production of oriented strand board, which is directly reflected on the quality of the material.As for Russian manufacturers, there are also manufacturers of high-quality building materials, including OSP-3, capable of competing with European manufacturers.
The best producers of oriented particle boards in Russia are:
- MLC “Kalevala”With a production capacity of over 600,000 m2, it is located in the Republic of Karelia.
- Company "STOD" (Modern wood processing technology), with a production capacity of over 500,000 m2, is located in the city of Torzhok.
- Kronospan plant (Kronospan)With a production capacity of over 900,000 m2, it is located in Yegoryevsk.
To help carry out construction work quickly and efficiently oriented strand boards, the work with which does not require "super efforts" and professional tools. The main advantages of the material include a wide range of formats, convenient labeling and low cost. These qualities are many times superior to the small deficiencies of OSP-3, and competent use of plates ensures a high level of operation.
Feedback from network users
It is cut easily, practically without chips. The main thing is not to hurry.
The range of use of such a plate is quite wide. Someone is stitching the ceiling, someone is using it as a material for partitions, I saw that they also sheathed the garage from the inside, and here I am using the OSB 9 mm thick slab. to cover the roof under the flexible tile.
The material is perfectly smooth, sheet sizes 1.25 meters by 2.5 meters.
It turns out like this. The material OSB-3 is moisture resistant, but this does not mean that it is waterproof. A week in the rain is not critical for him, but it is not worth diving into water. For especially wet rooms there are other materials. I recommend as a fairly versatile material for many types of work. I bought an OSB-plate in the winter even at the price of 14 Belarusian rubles per page. Now the price is about 17 rubles, but if you look at the shops you can find a bit cheaper. The material is not cheap, but there are no special options. Under a flexible tile or edged board to lay down closely, or OSB a plate. The board option is about 3 times more expensive.
In the section, an oriented strand board is a layered structure - several rows of shavings are tightly glued together under pressure and temperature. The main raw material is coniferous wood, most often it is pine. Large chips with a length of 8 to 15 cm are differently oriented in layers. That is why the PCB received such a name. In English, it sounds like an "oriented strand board" or OSB. The layered structure and large-sized chips increase the flexibility of the material and allow you to reduce the amount of glue, which in its properties makes the material closer to solid wood.
The binder is a mixture of water-resistant resins, boric acid and synthetic wax. In their composition, they contain a small amount of formaldehyde, which, when properly processed, practically does not harm human health.
Oriented strand boards, presented on the domestic market, are divided into 4 types:
- OSP-1 - the lowest quality variety. Not intended for use in high humidity conditions. Used in the manufacture of furniture and packaging.
- OSP-2 - suitable for the creation of supporting structures in rooms with low humidity.
- OSP-3 - used to create structural elements in any conditions.
- OSP-4 - a material capable of withstanding significant mechanical stress and is used in conditions with any humidity.
The last option is the most expensive, it is rarely found on the normal construction market. Therefore, it is most commonly used OSP-3 plate.
Technical characteristics of this material can be used in almost all areas of construction.
OSB-3 knowingly deserved such popularity among builders. This confirms the following list of its main advantages:
- Strength. The building material is able to withstand an average load of up to 640 kg / m3.
- Ease of processing. For cutting and grinding OSB no special tools are needed, regular drills, hacksaws and screws are suitable.
- Installation. For all their strength, these plates are light enough to be installed by one person.
- Density. When drilling and sawing material does not crumble and stratified. Large chips can keep the screws even at a distance of 1 cm from the edge of the plate without the formation of chips.
- Appearance. For some, the aesthetic properties of OSB boards are quite attractive. However, if desired, the sheets can be covered with any paint designed for working with wood.
- Moisture resistance. Certified material does not change its operational properties at a temperature of more than 20 ° C and a humidity of 65%.
- Fire safety. The building material is being tested for fire resistance and speed of spread of fire. The results show that it can be used for wall cladding. For additional protection, special impregnations and fire retardant paints can be used.
- Price. OSP-3 compares favorably with the cost of materials analogues with similar technical characteristics.
- Dimensions. Standard dimensions of the OSP-3 plate allow you to select sheets for various purposes: with smooth edges: 2440 * 1220, 2500 * 1250, with grooved ends: 2440 * 1220, 2440 * 590, 2450 * 590, 2500 * 1250. Plate thickness can vary from 9 to 22 mm.
Areas of use
Operational properties allow the use of OSP-3 for the following purposes:
- Создание обрешетки для крыши.
- Обшивка внешних и внутренних стен.
- Устройство черновых полов.
- Монтаж перекрытий.
- Двутавровые балки, сравнимые по своим прочностным характеристикам с бетонными и железобетонными конструкциями.
- Creating support surfaces for veneering materials or logs.
- High-quality packaging in the form of pallets, boxes and boxes.
- In furniture production, oriented strand boards of the third type are used for the manufacture of parts subject to increased load.
- Sandwich panels for the construction of frame houses.
Is there OSB-3 in North America?
The supply of OSP-3 that meets all standards in the territory of the Russian Federation is mainly carried out by two companies - this is Kronospan and Egger. Nevertheless, many dream to buy exactly the North American building material. After all, this region is famous for its extensive coniferous forests, and Canada and the United States - a serious approach to quality control. But with the purchase of a real OSB-3 plate from North American manufacturers, difficulties may be associated.
Plates from the USA and Canada can be called OSB-3 only if they are created by a special recipe and have passed the corresponding European certification. Such sheets have a special marker with a display of the grade, the recommended step of the rafters, the class of binder material and the logo of the organization that conducted the inspection. They are not deformed, practically do not swell, have high strength and durability.
How to choose a real North American OSB-3:
- When buying Canadian or American plates, make sure that they are OSB-3 labeled and marked EN-300.
- Review the test report enclosed with the certificate of conformity. The swelling ratio should be no more than 15%.
Not for nothing among the different types of oriented chip sheets, the OSP-3 plate has won the greatest popularity. Technical characteristics allow to use it in various areas - when creating floors and ceilings, walls and roofs, in furniture production and for the manufacture of complex structural elements. Being reliable and durable, it is really trustworthy.
What is swaps?
As part of the OSP - several layers fine (0.5–1.5 mm) chips of various shapes and sizes, oriented within each layer. The dimensions of wood chips for OSB are 1–20 cm in length and 1–50 mm in width. Read more about how to make chips, read here.
Clear orientation in the longitudinal or transverse direction notHowever, most of all large wood chips are oriented in the right direction with a tolerance of up to 60 degrees (in most cases, the turn relative to orientation does not exceed 30 degrees).
Due to the fact that most large chips are oriented in one direction, layer gains increased transverse or longitudinal rigidity and strength.
All layers are interconnected with a mixture of different natural and synthetic adhesives, each manufacturer using its own recipe and keeping it secret.
As a result all layersunited in a single carpet jointly react to any bending or twisting an effort, which provides high rigidity and strength compared to chipboard.
In this case, the plywood oriented chipboard is inferior in these parameters, because in plywood each layer consists of a whole sheet, therefore its strength and rigidity are much higher. All sheets correspond to the size accepted at the enterprise.
In the Russian Federation characteristics of PCB regulates GOST 32567-2013, which you can find here via this link.
The basis of this document was the international standard EN 300: 2006 "Oriented Strand Boards (OSB) - Definitions, classification and specifications". Therefore, plates that comply with GOST will also meet international standards.
The document applies only to the characteristics of the finished product, allowing the manufacturer to independently choose the most appropriate technology. We talked about general technological aspects in the article OSB production as a business.
Oriented strand sheets
GOST 32567-2013 and the international standard EN 300: 2006 divide oriented strand board (OSB shown in the photo) into strength classes:
In addition, all types of plates are divided byappearance of the front side:
and on the release into the air (emission) of formaldehyde:
Classes of strength and water resistance and application features
The class of OSP-1 include material that is unsuitable for the creation of load-bearing structures and has minimal moisture resistance. It is used for finishing inside dry rooms, plating of various panels. In addition, it applies for making furniture.
Despite the fact that OSP-1 has the lowest fracture strength, even it surpasses drywall in this parameter (GKL) of the same thickness and cement-shaving plates about which we told here.
OSP-1 is inferior in terms of rigidity of gypsum board and DSP, therefore it is necessary to reduce the distance between the parts of the batten, otherwise the skin will be pushed.
The class OSP-2 include more rigid and durable plates, which can act as carriers.
For example, due to the low price, OSP-2 of different thickness is often used for laying on a subfloor.
However they too not suitable for use in high humidity environmentstherefore, they do not make exterior cladding of buildings or CIP panels.
OSP-3 class includes plates that differ in their technical characteristics - durable and moisture-resistant elements that have found application as construction. OSP-3 of different sizes are often used as a subfloor, because they successfully replace the floorboard, and their price is noticeably lower.
OSB-2 and OSB-3 are comparable in strength, therefore the main difference in the minimum ability to absorb moisture, due to which the expansion as a result of swelling is also minimal.
Moisture-proof oriented chipboard class OSB-4 of all sizes are distinguished by the highest price, maximum rigidity and strength, therefore they are used only as construction, and on sites with maximum load.
In addition, OSP-4 have a minimum ability to absorb water, thanks to these characteristics they are distinguished by the most positive reviews and are used in the manufacture of CIP panels, as well as exterior cladding for frame houses.
Type of front surface and ends
The first experience of using oriented particle boards of different sizes - moisture-proof OSB for exterior work and ordinary for interior decoration, showed their high efficiency and significant superiority over other materials in terms of price / quality ratio.
As a result, there was a demand for higher quality products with a smooth and relatively smooth surface.
So the first appeared sanded slabs. Grinding retains a unique surface pattern, but eliminates all major irregularities. In addition, the tolerance of the thickness deviation for polished products is much lower and amounts to 0.3 mm, whereas for unpolished, a deviation of 0.8 mm is permissible.
Most of the plates have flat ends, however, the OSB, designed to create solid flooring, at the ends cut locksthat allow you to stack sheets without cracks.
Such oriented strand boards are called grooved. Read more about the grooved plates here.
Manufacturers also offer ground slabs, varnished or laminated.
The front side of the first ones is impregnated with a waterproof and wear-resistant varnish, while in the second, a thin wear-resistant film is deposited on the front side. Typically, such coatings are applied to a material intended for flooring and waterproofing the exterior.
3 classes of formaldehyde emission and environmental friendliness
To reduce the cost and increase the strength of OSB manufacturers forced to use adhesives containing formaldehyde. After hardening and polymerization, such adhesives have rather high resistance to water and good strength.
The use of adhesives that do not contain formaldehyde either does not provide the necessary strength, or greatly increases the cost of the finished product, depriving it of its main advantage - low price compared to plywood.
Therefore it was necessary to divide the PCA into formaldehyde emission classes. Minimum class E0,5 Allows up to 4 mg / 100 grams OSB. Wherein toxic content in the air for any time should not exceed 0.08 mg / m 3 .
For class E1 formaldehyde content should not exceed 8 mg / 100 grams, and the maximum allowable the air content is 0.124 mg / m 3 .
For class E2 the formaldehyde content in 100 grams of OSB should not exceed 30 mg, and the emission should not exceed 1.25 mg / m 3 .
At the same time, the average daily concentration of formaldehyde in residential premises should not exceed 0.01 mg / m3, as described in Appendix 2 of SanPiN 18.104.22.1682-00 “Sanitary and epidemiological requirements for residential buildings and premises”.
You can read this document by following the link. Even the conditionally safe class E0.5 allocates more than the standard amount of this poisonous substance, therefore, GSP can not usefor interior decoration living quarters without ventilation, because it can still render sufficient harm to the human body without observing these safety measures.
Dimensions and weight
Uniform standard i.e. standard OSB sizes does not exist, but most manufacturers adhere to the following length and width parameters in mm:
There are other sizes of OSP-1, OSP-2, OSP-3 and OSP-4. If instead of purchasing finished products, you prefer custom-made products, then you can make any size, up to a length of 7 meters.
Sheet thickness ranges from 6 mm to 25 mm in increments of 2 or 3 mm. but most popular plates with a thickness of 8–16 mm are considered. Also, quite often in the Russian market there are OSBs with a thickness of 9 mm, 10 mm, 12 mm and 15 mm, their cost usually increases with the increase in their parameters.
The mass of the sheet depends on its thickness and size, because the average density of a plate of any type is the same and amounts to 600–700 kg / m 3. Therefore, the OSB with dimensions of 1220x2440 mm is 12.5 kg with a thickness of 6 mm, with a thickness of 9 mm and 12 mm will be, respectively, more, and with a thickness of 22 mm - will be 42.5 kg.
The general principle of labeling PCB issued in Russia and abroad is the same. On one side indicate:
- dimensions (length, width, thickness),
- formaldehyde emission class
- type of front surface
- manufacturer name.
If you get swaps, intended for sale in America and Europe, then you need to know about the differences in labeling. The variety may not be listed as it is in EN 300: 2006, but in accordance with CSA O325, i.e:
- W - oriented strand board for covering the interior walls of dry rooms,
- 1F - rough flooring,
- 2F - OSB for fair flooring,
- 1R - material for the roof lathing without creating a support on the edges,
- 2R - the same, but with a support on the edges.
In addition, after the letter indicates a two-digit number, which means the maximum allowable distance between supports in inches, for example, 1F18.
If the CAP is suitable for various applications, then all tolerances are listed, for example, 1F18 / 2R20. Moisture resistance with such labeling also indicate separately:
- Interior - analogue OSP-1, with its technical characteristics suitable for use only in dry rooms.
- Esposure Type Binder - a plate with medium moisture resistance. It can be used in rooms with a slightly increased humidity level, and after treatment with protective preparations it can also be used for exterior decoration.
- Exterior Bond - material with maximum moisture resistance, suitable for any application even without additional treatment with hydrophobic agents.
Besides, may occur and other labels:
- SHEATHING SPAN - the distance between the axes of the lag in inches, if the numbers are indicated through a fraction, then the first value refers to the roof lags, the second value to the floor lags. If instead of the second value the figure 0 is indicated, then the oriented strand board is suitable only for use on the roof and cannot be laid on interfloor overlaps.
- THIS SIDE DOWN - bottom side label. On the outside of the OSB, with such an inscription, small grooves were made for diverting water, therefore improper installation will result in inefficient water being drained out during the rain, and the stove will begin to swell.
- STRENGTH AXIS THIS DIRECTION - this inscription is always accompanied by an arrow that indicates a direction perpendicular to the lags. In other words, an OSB with such an inscription must be laid so that the arrow is rotated 90 degrees relative to the lag.
Marking of laminated and varnished plates is not spelled out in generally accepted documents, so each manufacturer designates this type of material in its own way.
The same applies to wood-oriented plates with locks on the ends.
Price plates depends on:
- strength classes, water resistance and formaldehyde emission,
- sizes (length, width, thickness),
- sanding, varnishing, lamination or locks on the ends,
What is an OSB: composition, structure, production features and varieties
Externally, OSB plates are markedly different from MDF and particleboard due to the peculiarities of the structure. In the production of the material, thin and long wood chips are used, which are oriented longitudinally in the outer layers and transversely in the inner layers. Even in cases where the orientation is not too obvious, OSB can be recognized immediately by large, compared to other wood plates, pressed elements. The length of the chips in the plate is 75-150 mm, and width - 15-25 mm. Thanks to this orientation of the chips, the OSB plate acquired properties that greatly expanded its areas of application.
The original name of the material is OSB (oriented strand board), which, in English, means “oriented strand board. In Russia, both abbreviations are used - OSB and OSB. In some cases, you can hear the abbreviation of RSD, which is nothing more than a transliteration of English abbreviations.
OSB is produced by pressing flat wood chips mixed with a binding material. For this purpose, special equipment is used, first of all - modern high-tech pressing lines. Large plants in the US and Europe use ContiRoll - continuous pressing lines.
The production process of OSB boards goes through several stages:
1. Raw material sorting. The raw material for the production of oriented strand board is the timber of such tree species as aspen, spruce, pine and poplar. After the delivery of raw materials to the production line, a careful selection of logs is made.
2. Raw material preparation and chip production. After sorting, mechanized debarking of logs is performed. Next, peeled logs are cut into short pieces and sent to a planer installation, where they are split into chips along the direction of the wood fibers. At the end of the stage, the chips are dried by the conveyor method and sorted.
3. Preparing the composition for pressing and molding. As a binder for OSB, wax and adhesives based on paraffin, phenol-formaldehyde or isocyanate resin and boric acid are used, with which the chips are mixed in stages. Then, the resulting mixture is transferred to the molding station, where it is rolled out and molded into a homogeneous carpet before being sent under a press.
4. Plate pressing. The plate is pressed under a pressure of 5N / mm 2 and at a temperature required for the resin to solidify - 170–200 degrees. The temperature and pressure in the pressing zone is constantly monitored. After pressing and trimming, the material is subjected to control measurements of thickness and density, as well as checking for defects, and then aged for 48 hours before the final polymerization of the binder compositions.
5. Cutting and packaging. After a quality control check, OSB canvas is cut into elements of a standard format, the edges of the elements are profiled, and the resulting plates are sent to the marking and packaging line.
The main producers of OSB boards are Canada, Austria, the USA, the Baltic States. OSB production lines were opened in China, however, due to the poor quality of the plates, Chinese products did not become popular. In the period from 2012 to 2016, production of oriented strand boards was launched in Russia, where, with the quality of the material, it was possible to achieve a lower cost.
OSB Plate Types
Depending on the quantitative and qualitative parameters of the OSB plate is divided into 4 classes.
- OSB-1. Due to the lowest moisture resistance compared to plates of other classes, it can be used exclusively in dry conditions in non-loaded structures.
- OSB-2. The material is used for the erection of structures, with the carrying of a load on them. It is used exclusively in dry conditions.
- OSB-3. The class of material most widespread in finishing and construction. It can withstand load-bearing loads and has an optimal price / functionality ratio. The technical characteristics of the OSB-3 plate ensure the use of the material, including in wet conditions.
- OSB-4. These are the most durable and expensive materials. Increased reliability allows the use of material in building structures with large loads in wet conditions.
В данном случае термин "сухие условия" предполагает, что влажность воздуха при температуре 20 0 С, лишь на несколько недель в году может превышать порог в 65%. Термин "влажные условия" предполагает, что влажность воздуха при температуре 20 0 С, лишь на несколько недель в году может превышать порог в 85%.
Прочностные характеристики ОСП
The strength characteristics of OSB boards may vary slightly depending on the manufacturer. However, there are standards by which manufacturers and manufactured products must comply with them. Most often it is possible to meet the plates made according to the European EN 300 standard.
Mechanical properties of OSB boards according to EN 300:
The result clearly demonstrates that the oriented strand board has an extremely low vapor permeability comparable to the same property of foam glass or linoleum on a fabric basis. The whole problem lies in the production technology. OSB stove is not reading wood, but a mixture of wood and resin, which have low vapor permeability.
Manufacturability OSB plates
Due to the composition and structure, oriented strand boards are amenable to various types of processing. Their planing, grinding, drilling, grinding, sawing and milling are allowed. OSB can be handled with both stationary and portable electric and hand joinery tools, which are recommended to be equipped with hard metal blades.
In the process of working with OSB boards it is necessary to observe the following conditions:
- using tools with sharply sharpened carbide blades,
- maximum attention to even tool management,
- reliable fixation and ensuring an even protrusion of the web
- reduced tool speed when sawing.
One of the key points of working with oriented strand board is ensuring safety for life and health. Dust emitted during mechanical manipulations is a strong carcinogen, therefore it is strongly recommended to carry out any work with OSB in overalls, it is necessary to use a mask or respirator and choose instruments with suction. It is highly desirable presence in the room exhaust ventilation.
The ability of OSB boards to hold fasteners
The combination of high density and fiber OSB provides all the conditions for high-quality retention fasteners - fixing strength even at the outer edge of the panel is quite high. All types of fasteners suitable for wood-based panel materials, including screws, nails and staples, are allowed. Fix the fasteners can be already 10 mm from the edge of the plate without fear of breakage or delamination of the material. In a pinch, you can hammer in nails and at a distance of 6 mm from the edge, but this requires special care.
Oriented strand boards of all four classes have a good navel. However, you should be aware that there are certain requirements for fasteners used for mounting panels. The length of the fastener must not be less than 2.5 times the thickness of the plate, but must not be less than 50 mm. If you need to use staples you need to pay attention to the thickness of the wire staples, it must be at least 1.53 millimeters.
According to the standard DIN 1052-2 for OSB plates it is recommended to use fasteners made of stainless or galvanized steel. There are certain requirements for the shape of the nails - the best option are nails with a flat cap and thread, chute or ring groove. Due to the high resistance to pulling, it is not allowed to excessively penetrate the nail head into the slab. When using nail guns during installation, you must use special glasses and strict adherence to safety regulations.
The ability of OSB plates for bonding and staining
For oriented strand boards, the use of high-quality paints used for surfaces made of natural wood is permissible. To obtain an aesthetically attractive and stable result, a number of specific requirements must be met when processing OSB:
- Mandatory priming before painting. When using polished slabs, primer mixtures must be applied in two layers due to the increased ability of the polished OSB to absorb paint, linseed oil and stain.
- The use of primer coatings with certain properties. For OSB, it is desirable to use formulations that provide a high level of protection against mold. The slabs can also be stained well, but it does not provide good material protection from moisture, and therefore is used less frequently.
- Easy grinding of the surface after applying each layer of primer or paint. Such processing provides a uniform distribution of coloring compositions and an attractive appearance of the panels.
- Use durable waterproof paints. The optimal solution for oriented strand board is the application of the finishing layer using varnishes or acrylic-based lacquer paints.
Gluing of OSB panels is possible with the help of any adhesive compositions used for wood. Grinding the surface before adhesive treatment will significantly increase the strength of the joint.
Biological resistance OSB
OSB plates have sufficient biological stability, however, with prolonged exposure to high humidity and temperature extremes, the risk of material damage from molds increases. First of all, it concerns panels made of spruce or aspen chips - pine and maple chips show a higher resistance to mold.
To protect the OSB plate from the effects of fungi and bacteria, you need the additional use of waterproof materials, as well as the use of paints and varnishes with protective properties.
OSB affected by mold due to the negative impact of the external environment.
Ecological purity of the material
One of the controversial points in the technical characteristics of OSB plates – harmfulness and toxicity of the material to humans. Indeed, melamine-formaldehyde, urea-formaldehyde and phenol-formaldehyde resins are used as binders for OSB, which, under the influence of high temperatures, release free formaldehyde. That is why there is a perception that this material is more dangerous than chipboard and plywood. However, this is nothing more than a delusion.
The fact is that the content of glue and resins in the composition of oriented strand boards does not exceed 3% - for the particle board this indicator is 12-14%. Thus, manufacturers managed to achieve emission (emission) of formaldehyde not higher than 8 mg per 100 grams of dry plate. Some experts argue that even if OSB plates are produced in violation of environmental requirements, they will have less formaldehyde emissions than chipboard and even plywood. In addition, today formaldehyde resins are increasingly being replaced by glue based on MDI, an aromatic diisocyanate, which has extremely low toxicity. But the cost of these materials is higher. Continuous improvement of the technology of creating PCBs can significantly improve the environmental friendliness of the material.
In Europe, OSB plates according to the level of formaldehyde released are divided into three groups:
- Е1 - up to 0.1 ppm, when converted to mg / m³ will be - 0.125 mg / m³,
- Е2 - 0.1 - 1.0 ppm, when converted to mg / m³, it will be from 0.125 - 1.25 mg / m³,
- E3 - 1.0 - 2.3 ppm, when converted to mg / m³, will be from 1.25 - 2.87 mg / m³.
In construction, it is allowed to use materials with formaldehyde emission level E1 - E2. Materials with an E3 emission level are prohibited.
No matter how environmentally friendly the material is, the release of formaldehyde in a certain amount still happens. Most of all, it stands out during the first year of operation of the material.
OSB Fire Safety
To determine the fire safety of the material, the classification according to the degree of flammability is used according to GOST 30244-94.
- Class G-1 (low combustible). Materials with a degree of damage in the area of not more than 65% with a degree of destruction of not more than 20%. The flue gas temperature during combustion does not exceed 135 degrees. Melt drops are not formed.
- Class G-2 (moderately flammable). The group of materials, the degree of damage to which during combustion is not more than 85%, the degree of destruction does not exceed 50%, and independent burning is a maximum of 30 seconds. Flue gas temperature - up to 235 degrees. Melt droplets are not allowed.
- Class G-3 (normally flammable). The flammability characteristics are similar to class G-2 - with a discrepancy in self-burning (300 seconds) and flue gas temperature (450 degrees).
- Class G-4 (highly flammable). Materials of this class have a degree of damage on the area when burning more than 85%, the degree of destruction is more than 50% percent, and independent burning - more than 300 seconds. The temperature of the flue gas exceeds 450 degrees.
Because of the wood shavings that make up the OSB, it is highly flammable, forcing it to fall into class G-4. To improve fire safety in rooms lined with OSB boards, as well as structures made of this material, it is recommended to install a layer of refractory material - for example, mineral wool. In addition, manufacturers seek to improve the class of flammability of oriented strand boards by adding flame retardants (boric acid) to the composition or by additional impregnation of the panel with flame retardants.