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Properties and characteristics of OSB boards. OSB boards: types, sizes, technical characteristics, manufacturers, photos and videos Material osb 3

Sheet building materials are used in frame house construction for dry leveling of planes. One of these materials is OSB board (OSB). She pushed aside GKL. And all because, with good technical characteristics, it has a low price.

What is OSB board and OSB

One of the sheet building materials is OSB (also called OSB). The name is an abbreviation of the full name of the material - “oriented strand board”. That is, it is correct to call this material OSB. The second name - OSB - comes from the transliteration of the English version of the name - OSB ( oriented strand board). English letters were simply replaced with similar ones in Cyrillic.

OSB is a multilayer material (3 or more layers). Each layer consists of wood, ground into chips, mixed with resins. The wood chips used are long and thin (several millimeters thick, up to 7 cm long). The chips in the layers are located in different directions: the outer layers have a longitudinal orientation, the inner layers have a transverse orientation. Due to this, high elasticity and dimensional stability are achieved. Various resins are used as a binder. They make the material waterproof, but contain formaldehyde. It is the content of this substance that stops many from using OSB. But, if the material is produced in accordance with GOST, formaldehyde emissions do not exceed those of wood. But this can only be verified in laboratory conditions. So the average buyer can only rely on the inspection authorities. Or choose a different material.

Types of OSB

Depending on the consumer properties, oriented strand boards are produced in several types:

If you need moisture-resistant OSB, carefully choose the manufacturer. Be prepared for the fact that OSB 3 is more expensive than non-moisture resistant brands. You will have to pay even more money for OSB 4. We do not recommend looking for cheap material. Too many people complain that purchased OSB 3 swelled by 3-8 mm due to humidity, in some cases it even blossomed or became overgrown with fungi. All this is due to attempts to reduce costs. To do this, they use less disinfectants and a cheaper binder. Chinese manufacturers use deciduous wood instead of pine wood chips, which is easily affected by fungi and diseases.

Properties and technical specifications

OSB boards compete with other sheet materials both in the field of construction (for covering frames, creating formwork) and in the field of finishing (leveling walls, floors, ceilings). This is facilitated by the properties of OSB:

Once again, please note that moisture resistance and resistance to deformation are characteristic of OSB, which was made in compliance with the technology. Unfortunately, Russian-made material is not of high quality. Less powerful presses are used, they try to save on binders, and do not apply markings. As a result, there are many examples of negative experiences: slabs swell from moisture, they warp, the glue is washed out... The solution is to look for slabs made imported (Europe or the USA). Due to the rise of the dollar, they now have considerable prices; there are very few of them on the market, but, if desired, you can find them or order them for delivery.

The situation is aggravated by the fact that it is impossible to distinguish moisture-resistant OSB3 from non-moisture-resistant OSB2 or 1 by appearance. The latter cost much less. Unscrupulous sellers sell cheaper ones under the guise of being moisture resistant. This is where trouble starts. As a way out, you can do this: buy one sheet of OSB 3, check its behavior at high humidity. If there are no visible changes, buy a batch.

Application area

The properties of OSB allow this material to be used as a construction or finishing material. Here are the types of work it can be used for:

• Covering frames and walls inside and out.
• Leveling the floor and ceiling.
• Laying rough or finished floors along joists.
• Removable formwork when working with concrete.
• Continuous sheathing for metal tiles, slate,.
• Production of SIP panels and thermal panels.

There is constant debate among developers about how safe OSB board is. Its production uses resins that emit formaldehyde. Manufacturers claim that the release of this substance does not exceed 1%. Materials with such formaldehyde emissions are considered absolutely safe. Wood releases approximately the same amount of this substance. Therefore, such materials are allowed for the construction of children's furniture. In addition, OSB boards with emissions of 0.5% appeared. They can be distinguished by two criteria: the name contains the prefix Bio or Green and they are more expensive.

Please note that the level of formaldehyde emission must be controlled. Each batch of material must be checked and the actual parameters indicated in the accompanying documents. Despite all the arguments, not everyone considers this material safe, preferring to use natural material - boards. They are, without a doubt, an environmentally friendly material, but the boards take longer to work with and are more expensive. In general, everyone decides for themselves whether to use OSB boards or not.

Oriented Strand Board Dimensions

Since OSB boards have different purposes, different sizes may be convenient. The situation with the sizes of OSB boards is not simple. 1220*2440 mm and 1250*2500 mm are always on sale. There are also formats 1250*2800 mm, 1250*3000 mm, 1200*6000 mm, but they are extremely rare on our market, although in many cases they are much more convenient to use. By choosing the right size, you get rid of the need to “grow” the missing centimeters or saw off the extra ones. But there are not many of them on the market, since these are imported slabs, and importing is now difficult...

The OSB board can be of different thicknesses - 9 mm, 12 mm, 15 mm, 18 mm, 22 mm, 25 mm. Each type of use has its own thickness:

• Wall and ceiling cladding - from 9 mm.
• Continuous sheathing for roofing materials - from 12 mm.
• An OSB board with a thickness of 15 mm or more will be used on the floor.

Another application of OSB boards is removable formwork for concrete work.

OSB board is a convenient building material. You can cut it with a regular wood saw, use a grinder with a cutting disc, or use a jigsaw. The material drills well; screw nails can be used without pre-drilling. But then their hats stick out, which is not always convenient.

Before finishing, the OSB board is coated with a primer. It is selected depending on the finishing materials - to equalize absorbency and improve adhesion to other materials.

Oriented strand board (OSB, OSB, OSB - short for the English expression oriented strand board) is a modern structural and finishing material that used for various works.

OSB was conceived as inexpensive alternative plywood and, because the ability to use non-commercial wood to make chips reduces the cost of the finished product.

• what is OSB;
• what types of oriented strand boards are there;
• what regulatory documents regulate the quality and characteristics of OSB boards;
• what sizes do chip OSBs have, and does their price depend on this;
• how much does this material cost?
• advantages and disadvantages compared to other structural and finishing materials;
• What is OSB used for?

As part of the OSB - several layers thin (0.5–1.5 mm) of various shapes and sizes, oriented within each layer. The sizes of wood shavings for OSB are 1–20 cm in length and 1–50 mm in width. You can read more about how chips are produced.

Clear orientation in longitudinal or transverse direction No However, the majority of all large wood chips are oriented in the desired direction with a tolerance of up to 60 degrees (in most cases, the rotation relative to the 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 connected to each other using a mixture of various natural and synthetic adhesives, and each manufacturer uses its own recipe and keeps it secret.

As a result all layers, combined into a single carpet, react together to any bending or twisting an effort, which provides high rigidity and strength compared to chipboard.

In this case, oriented strand board is inferior to plywood in these parameters, because in plywood each layer consists of a whole sheet, so its strength and rigidity are much higher. All sheets correspond to the size accepted at the enterprise.

Regulations

In the Russian Federation, characteristics of OSB regulated by GOST 32567-2013, which you can view at this link.

The basis of this document was the international standard EN 300:2006 “Oriented Strand Boards (OSB) – Definitions, classification and specifications”. Therefore, slabs that comply with GOST will also comply with the international standard.

The document applies only to the characteristics of the finished product, allowing the manufacturer to independently choose the most suitable technology. We talked about general technological aspects in the article.

Types of oriented strand sheets

GOST 32567-2013 and the international standard EN 300:2006 divide oriented strand boards (OSB shown in the photo) into strength classes:

1. OSB-1 (OSB-1).
2. OSB-2 (OSB-2).
3. OSB-3 (OSB-3).
4. OSB-4 (OSB-4).

In addition, all types of slabs are divided By appearance of the front side:

• unpolished;
• polished,

and on the release of formaldehyde into the air (emission):

1. E0.5.

Strength and water resistance classes and application features

The OSB-1 class includes a material that is unsuitable for creating load-bearing structures and has minimal moisture resistance. It is used for finishing inside dry rooms, covering various panels. In addition, it applies for furniture making.

In terms of rigidity, OSB-1 is inferior to gypsum plasterboard and fiberglass board, so it is necessary to reduce the distance between the sheathing parts, otherwise the sheathing will be pressed through.

The OSB-2 class includes more rigid and durable boards that can act as load-bearing elements.

For example, due to its low price, OSB-2 of various thicknesses is often used for laying on subfloors.

However, they too not suitable for use in high humidity conditions, therefore they are not used to make external cladding of buildings or SIP panels.

The OSB-3 class includes slabs that differ in their technical characteristics - durable and moisture-resistant elements that have found application as structural. OSB-3 of various sizes is often used as a subfloor, because they successfully replace floorboards, and their price is noticeably lower.

In terms of strength, particle board OSB-2 and OSB-3 are comparable, so the main difference is the minimal ability to absorb moisture, due to which expansion due to swelling is also minimal.

Moisture-resistant oriented strand boards class OSB-4 of all sizes are distinguished by the highest price, maximum rigidity and strength, therefore they are used only as structural, and in areas with maximum load.

In addition, OSB-4 has a minimal ability to absorb water, thanks to these characteristics they have the most positive reviews and are used in the production of SIP panels, as well as as external cladding of frame houses.

Type of front surface and ends

The first experience of using oriented strand boards of different sizes - moisture-resistant OSB for exterior use and conventional ones 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 an even and relatively smooth surface.

This is how the first ones appeared polished slabs Sanding preserves the unique surface pattern, but eliminates all major irregularities. In addition, the tolerance for thickness deviation for sanded products is much lower and amounts to 0.3 mm, while for unpolished products a deviation of 0.8 mm is acceptable.

Most slabs have straight ends, but OSB, designed to create a continuous flooring, has locks are cut out at the ends, which allow you to lay sheets without gaps.

These oriented strand boards are called tongue and groove. You can read more about tongue and groove slabs.

Manufacturers also offer polished slabs, varnished or laminated.

The front side of the former is impregnated with waterproof and wear-resistant varnish, while the latter have a thin wear-resistant film fused to the front side. Typically, such coatings are applied to material intended for finished flooring and external waterproof finishing.

3 formaldehyde emission classes and environmental friendliness

To reduce costs and increase the strength of OSB, manufacturers forced to use adhesives containing formaldehyde. After hardening and polymerization, such adhesives have fairly high resistance to water and good strength.

The use of adhesives that do not contain formaldehyde either does not provide the required 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 OSB into classes based on formaldehyde emission. Minimum class E0.5 allows up to 4 mg/100 grams of OSB. Wherein content of a poisonous drug in the air for any time should not exceed 0.08 mg/m3.

For class E1 formaldehyde content should not exceed 8 mg/100 grams, and the maximum permissible the content in the air is 0.124 mg/m3.

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/m3.

At the same time, the average daily concentration of formaldehyde in residential premises should not exceed 0.01 mg/m3, as stated in Appendix 2 of SanPiN 2.1.2.1002-00 “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 releases an amount of this toxic substance that exceeds the standards, so OSB can not use For interior decoration residential premises without ventilation, since it can still cause sufficient harm to the human body without observing these safety measures.

Dimensions and weight

Single standard that is, standard OSB sizes does not exist, but most manufacturers adhere to the following length and width parameters in mm:

• 1250x2500;
• 1200x2400;
• 590x2440.

There are other sizes of OSB-1, OSB-2, OSB-3 and OSB-4. If you prefer something made to order instead of purchasing finished products, then they can make you 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. However most popular slabs with a thickness of 8–16 mm are considered. Also quite often on the Russian market there are OSB thicknesses of 9 mm, 10 mm, 12 mm and 15 mm, their cost usually increases according to the increase in their parameters.

The weight of the sheet depends on its thickness and size, because the average density of any type of board is the same and is 600–700 kg/m3. Therefore, the weight of OSB with dimensions 1220x2440 mm is 12.5 kg with a thickness of 6 mm, with a thickness of 9 mm and 12 mm it will be correspondingly greater, and with a thickness of 22 mm it will be 42.5 kg.

Marking

The general principle of marking OSB produced in Russia and abroad is the same. On one side indicate:

• variety;
• dimensions (length, width, thickness);
• formaldehyde emission class;
• type of front surface;
• manufacturer's name.

If you purchase OSB, intended for sale in America and Europe, then you need to be aware of the differences in labeling. The variety may not be specified in the same way as in EN 300:2006, but in accordance with CSA O325, that is:

• W – oriented strand board for cladding internal walls of dry rooms;
• 1F – rough flooring;
• 2F – OSB for finishing flooring;
• 1R – material for roof sheathing without creating support at the edges;
• 2R - the same, but with support at the edges.

In addition, after the letter a two-digit number is indicated, which means the maximum allowable distance between supports in inches, for example, 1F18.

If OSB is suitable for various applications, then all tolerances are listed, for example, 1F18/2R20. Moisture resistance with this marking is also indicate separately:

1. Interior– an analogue of OSB-1, with its technical characteristics suitable for use only in dry rooms.
2. Esposure Type Binder– a board with average moisture resistance. Can be used in rooms with slightly increased humidity levels, and after treatment with protective preparations can also be used for exterior decoration.
3. Exterior Bond– a material with maximum moisture resistance, suitable for any application even without additional treatment with hydrophobic agents.

Besides, may meet and other inscriptions:

1. SHEATHING SPAN– the distance between the axes of the joists in inches, if the numbers are indicated through a fraction, then the first value refers to the roof joists, the second to the interfloor joists. If the number 0 is indicated instead of the second value, then the oriented strand board is only suitable for use on the roof and cannot be laid on interfloor floors.
2. THIS SIDE DOWN– bottom side mark. On the outside of the OSB with this inscription, small grooves are made to drain water, so improper installation will lead to the fact that during rain, water will not be drained effectively and the slab will begin to swell.
3. STRENGTH AXIS THIS DIRECTION– this inscription is always accompanied by an arrow that points in the direction perpendicular to the joists. In other words, OSB with such an inscription must be laid so that the arrow is rotated 90 degrees relative to the joist.

The marking of laminated and varnished boards is not specified in generally accepted documents, so each manufacturer designates this type of material in its own way.

The same applies to wood-oriented boards with locks on the ends.

Price

Price of slabs depends on:

• strength, water resistance and formaldehyde emission classes;
• dimensions (length, width, thickness);
• sanding, varnishing, laminating or locking the ends;
• manufacturer.

The most popular strength class is OSB-3 and emission class E1 - it is quite difficult to find OSB particle boards of other emission classes, so most often they are made to order, so the price is discussed individually.

It is also worth noting that with the same length and width parameters, but with different OSB thicknesses - for example, 9mm, 12mm, 15 or 18mm, the price for them will also be different.

Technical characteristics and comparison with other finishing materials

Here main competitors oriented strand boards:

• plywood (No. 1);
• Chipboard (No. 2) (link to chipboard);
• Fiberboard (No. 3);
• GKL (No. 4);
• glass-magnesite sheet (No. 5);
• smooth slate (No. 6);
• DSP (No. 7).

In parentheses are the numbers assigned to them, in the order in which we included them in the table where you can compare Main settings and technical characteristics, that is:

• density;
• the possibility of use as a structural element, that is, subflooring, roofing, etc.;
• thermal conductivity;
• vapor permeability;
• flammability (ability to sustain combustion);
• toxicity under normal conditions/in case of fire.

Density finishing material affects the weight of the sheet and can make it difficult to climb to the upper floors and install. Therefore, the low density of OSB is a serious advantage, which is further enhanced if we take into account the possibility of using oriented strand boards as a structural material.

With low OSB density has high strength, so you can do from it:

• rough and finished floors in residential premises;
• roof decking;
• steps on stairs;
• removable formwork;
• SIP panels;
• various fences.

By thermal conductivity OSB is comparable to plywood and superior to most finishing materials, second only to DSP and fiberboard. However, in such an important parameter as vapor permeability, it is inferior to most competitors.

Because of this, in houses lined with OSB, it is necessary to take special measures to remove moisture and protect against condensation. For more information about the effect of vapor permeability on the humidity in the house and the condition of the walls, read the article (Application of OSB).

Oriented Strand Boards belong to the class of flammable fire hazardous materials.

Manufacturers are trying to reduce the level of flammability using pyrophobic preparations, but even such boards are superior to plywood and wood in this parameter.

In addition, high strength finished slabs manages to get only using formaldehyde-based adhesives, which is a strong poison, and therefore OSB is not environmentally friendly.

Therefore, covering the internal space with OSB sheets, although inexpensive, leads to exceeding the maximum permissible concentration of this substance, which negatively affects well-being and health.

However, all the significant disadvantages of this material can be neutralized by proper use. After all, even in E2 class slabs, the rate of formaldehyde release is so low that any ventilation or periodically opened window can easily cope with it.

But you still need to know - during a fire, OSB emits not only carbon dioxide and carbon dioxide, but also many toxic substances posing a threat, causing harm to health.

Installing fire safety systems, including smoke detectors, is useful in any home. After all, during a fire, the main danger is not toxic substances, but smoke, which makes it difficult to leave the room.

In addition, many pieces of furniture and household appliances release toxic substances in large quantities during a fire. That's why in case of a small fire OSB sheathing poses no threat, if the fire safety systems work properly and extinguish the fire. If the systems do not work and the fire gains strength, then there will be enough smoke and toxic substances even in houses without such cladding.

Video on the topic

Briefly and concisely about the main properties, advantages and disadvantages, benefits and possible harm of OSB in the video presented:

Conclusion

OSB boards are a good and modern structural and finishing material that has both advantages and disadvantages. However, all the disadvantages are compensated by the correct use of boards, and the advantages make OSB more attractive than other materials.

After reading the article, you learned:

• what is OSP, and how to decipher this abbreviation;
• about the characteristics and properties of OSB boards;
• what is the difference, for example, between OSB-2 and OSB-3 and other types of oriented strand boards;
• about the price of chip OSB;
• about the features of their use and other parameters.

In contact with

Oriented strand board has recently appeared on the construction market - it has replaced the previously popular chipboard. The material has outstanding technical data, thanks to its multilayer structure and special manufacturing technology. Information with specific numbers will help you understand the characteristics of the material and its level of safety.

Accurate knowledge of the technical characteristics of the OSB board and the level of its harmfulness will help to understand how advisable its use in construction is. The raw material used in the manufacture of strand board is large sized wood shavings. It is bonded using waterproof phenol or formaldehyde resin under pressure and high temperature.

OSB boards are made from large-sized wood chips

The predecessor of this material is chipboard. Their main difference is the arrangement of chips in the layers. OSB is characterized by a transverse direction in the inner part and a longitudinal direction on the outside. A total of three or four layers are made, alternating the direction of the particles. This allows you to achieve special strength parameters. As a result, chipboard is gradually replacing its more progressive counterpart.

The chips underlying the oriented slab have a length of 7.5 to 15 cm. The norm for the width and thickness of internal particles is 1-1.2 cm, 0.5-0.8 mm, respectively. Smaller chips are sifted out and used to produce less durable chipboard. Pine or aspen are used as raw materials. Modern equipment and the latest technologies make it possible to achieve maximum uniformity of the slab composition in all directions. High-quality material has no cracks, voids or chips.

Depending on strength, manufacturers divide products into main classes:

• OSB 1 - belongs to the low class. The area of ​​their use is dry rooms and structures that are not subject to special loads, for example, cladding or furniture.
• OSB 2 is a medium strength class. They can be used both as cladding and for load-bearing structures, but in dry rooms. For example, these could be partitions inside a room.
• OSB 3 – high class. Operation under good load and high humidity is possible. External cladding of the building.
• OSB 4 – the board has special strength characteristics: it is designed for a humid environment and constant intense mechanical stress. Cladding of houses without additional cladding.

In addition to the alphanumeric classification, there are separate types of oriented strand boards:

• Laminated – additionally treated with laminate components. The characteristics of OSB boards make it possible to successfully use it for covering floors and making furniture. They can be used to make interior partitions and be used for formwork several times.
• Grooved - grooves and protrusions are applied to the ends of such slabs. By driving them into each other, a tight connection without gaps is obtained.
• Lacquered - used in the furniture industry.

The tongue-and-groove slabs have recesses and protrusions at the ends for a tight connection with each other

The material can be produced either with or without coating. As a facial treatment, paint, anti-moisture and anti-fire compounds, and bioprotection are used.

Production technology and scope of OSB boards

Understanding the manufacturing processes of oriented strand boards will help you better understand how and where they can be used and what the benefits of this material are. Production stages:

1. 1. Selection of raw materials. At this stage, the trunks of thin non-commercial trees are sorted.
2. 2. Cutting. Selected trees are cut into small pieces, which then serve as blanks.
3. 3. Grinding. The blanks are placed in a special machine that chops the wood into chips. It spills onto the conveyor belt. The size of the chips can be adjusted depending on what kind of slab you need to get.
4. 4. Drying.
5. 5. Sorting of wood chips. Small chips are separated from large ones.
6. 6. Gluing. A binding element – ​​phenol or isocyanate – is added to selected chips of the required size. It gives the future building material moisture resistance and strength. Paraffin is added to the mixture, and it is all mixed in a special drum.
7. 7. Formation of the slab. The chips are stacked in layers. The machine does this using scales and magnets.
8. 8. Pressing. The resulting tape is subjected to a pressure of 5N/mm2 at high temperature. The elements adhere firmly to each other, resulting in a single slab. After cooling, pieces of the desired size are cut from it.

The range of applications for OSB is wide:

• OSB-4, due to its strength and moisture resistance, is used for the construction of frame houses and outbuildings. The material produces inexpensive temporary housing.
• Arrangement is the best option for an oriented slab. It holds shelves with heavy objects, racks, and heating radiators well.
• The building material is used to cover walls, ceilings and floors during the interior decoration of buildings. A perfectly flat, smooth surface is convenient for plastering, painting, and wallpapering.
• A large area of ​​application is the furniture industry, packaging production. Strength, low price and low weight make oriented strand boards suitable for the manufacture of upholstered and cabinet furniture, and shipping containers.

The material is used in combination with both wooden and metal structures.

This material is widespread in construction due to its attractive properties from the point of view of the builder.

Thanks to the large chips in the composition, OSB boards perfectly hold any fasteners

• OSB is easy to process - in order to work with them, it is enough to have a standard set of carpenter's tools on hand. The slab can be sanded, cut, planed, sawed. It will not crumble or break if holes are punched or drilled in it.
• Large chips provide high retention capacity. Thanks to its contents, nails can be driven into the slab at a distance of six millimeters from the edge. The plate holds any fasteners well without chipping. You can use wood glue to secure it.
• The average density of the slab is 640 kg/m3. This also includes the strength of the material, which depends on elasticity:

• Moisture resistance is the level of thickness swelling after the slab has been in water for 24 hours. The table shows the percentage of the total volume:

• Fire safety. Since the slabs are made of wood chips, they are easily ignited and burn well. For this reason, it is recommended to use OSB in combination with non-combustible insulation or cladding materials. For example, mineral wool or metal siding.

During construction, it is better to use non-flammable insulation or cladding materials

OSB is convenient to use in construction, but together with durable load-bearing structures and fire protection. The high level of elasticity of the slabs allows them to withstand earthquakes well. Compared to stone, they are superior in this regard. Disadvantages include the need to use a respirator during installation and processing to protect against small chips and emitted vapors from the resin.

Hazard level of OSB boards for human health

Sellers boldly call this material environmentally friendly. At the same time, you can find a lot of information that NDEs are terribly harmful to health. It is not difficult to understand the essence of the issue. The composition of oriented boards includes types of resins:

• phenol-formaldehyde;
• melamine-formaldehyde;
• urea-formaldehyde.

They are obtained synthetically and give the slabs high-tech properties. OSB will be hazardous to health during further use as a building material if the rules of manufacturing technique are not followed. To avoid purchasing low-quality products, check the certificates when purchasing.

In Russia, the European standard DIN EN120 is recognized, which classifies slabs with chips according to the level of formaldehyde they contain, a substance that produces harmful fumes. The classification looks like this (calculation per 100g of dry matter): E0 - up to 6.5 mg, E1 - up to 10 mg, E2 - 10-20 mg and E3 - up to 30 mg.

There is nothing to worry about when using OSB for exterior finishing, because... the concentration of released vapors in the air will be insignificant. The use of the second and third types for interior cladding of residential premises is strictly prohibited, because the level of vapor released into the room will exceed the permissible limit. E2 and E3 are suitable for attics, sheds and sheds.

According to production rules, all products such as chipboards must be tested for the level of synthetic resin content. Based on its results, a corresponding certificate is issued. Pay attention to the smell of the building material: if it is pungent, like formaldehyde or plastic, the product is toxic and cannot be used indoors.

OSB is a material with good performance, suitable for construction in all respects. By comparing it with other options and weighing the pros and cons, you can easily make the right decision.

OSB stands for Oriented Strand Board - a board made of oriented strands, or OSB in Russian. This is a modern construction and finishing material, consisting of 90% wood chips bound with synthetic waterproof resins. The slabs are formed by 3-4 layers of thin chips up to 15 cm long, pressed at high pressure and temperature, and the direction of the chips in each layer is different.

OSB boards can be used for:

• production of sandwich panels and construction of frame houses,
• when installing floors,
• covering walls, ceilings, floors,
• for covering roofs,
• during auxiliary work (installation of formwork, scaffolding),
• for the manufacture of auxiliary buildings (sheds, storage facilities), street structures, fences,
• as structural elements of furniture.

High-quality OSB complies with the EN 300 OSB standard, which imposes requirements for environmental safety and technical parameters of boards.

Types of plates and their features

There are 4 main types of slabs produced:

• OSB-1- low strength and low moisture resistance, used for interior work, in the manufacture of furniture,
• OSB-2- high strength and low moisture resistance, used for internal partitions, load-bearing structures, floors,
• OSB-3- high strength and high moisture resistance, ideal for outdoor use,
• OSB-4- ultra-high strength and high moisture resistance, used for load-bearing elements, walls, roofs.

The moisture resistance of the board depends on the composition of the glue used, and the strength depends on the number of layers and the relative position of the chips in them.

In addition, there are boards with a varnished or laminated surface on one side, which, for example, can be reused for the manufacture of formwork. For installation on a horizontal surface, you can use OSB with tongue-and-groove joints at the ends on 2 or 4 sides.

The most common standard slab sizes are:

• 122 * 244 cm,
• 122 * 366 cm,
• 125 * 250 cm * 6 –40 mm,
• 125 * 370 cm,
• 125 * 600 cm.

Pros of OSB

Manufacturers sometimes refer to OSB as “improved” wood. It is just as durable, light and easy to process, but at the same time it is free from such disadvantages as fire hazard, susceptibility to rot and mold, the presence of voids and knots. In terms of technical properties, OSB is superior to chipboard, fibreboard, MDF and even plywood.

Factory conveyor production allows for stable dimensions and uniform thickness throughout the slab. OSB provides excellent heat retention; it is not subject to deformation and destruction in water. For its processing, the same tools and materials are used as for wood. Large sheet sizes allow the construction of walls with a minimum number of joints. The service life of structures made from such plates is practically unlimited.

Cons of OSB

Recently, there has been a lot of material about the dangers and negative effects of OSB on health. All the criticism is related to the use of phenol in synthetic resins, which are used to join wood chips and release carcinogenic substances. Today, most European manufacturers have switched to polymer resins that do not include formaldehyde and are completely safe; such boards are usually labeled ECO-, Green-.

In any case, before purchasing OSB for building a house, you should familiarize yourself with the certificates for this material and make sure that it corresponds to class E1, or even better, E0 (the emission class determines how much formaldehyde compounds are released into the environment).

For interior work and furniture making, it is permissible to use only OSB intended for interior work, and if there are doubts about its quality, insulate it well with plasterboard, finishing materials and floor coverings and take care of ventilation in the room. OSB-3 and -4 can only be used for work outside the home.