The Better To Cut Osb Slab
My tips for installing OSB boards (OSB)
Recently I have noticed that more and more houses are sheathed with OSB (OSB. Oriented Strand Board). And there are several good reasons for this. After all, OSB boards. It is an affordable and reliable material with an absolutely homogeneous internal structure.
What makes OSB boards the best material for external cladding of frame structures? First of all. It is dimensional stability. That is, all OSBs have exactly the same dimensions after they leave the sawmill. In addition, OSB has an absolutely homogeneous composition. This means there are no voids or air bubbles in them. Another OSB. It is an environmentally friendly material that is suitable for both outdoor and any indoor work. OSB is made from fast growing trees and is virtually waste-free.
But the best part. That’s what OSB is. It is an economically advantageous purchase because this material is much cheaper than plywood comparable in quality and physical characteristics.
When you install OSB boards, remember about two things: about the gaps between the boards and about the fastener card.
All wood building materials change their size, because wood reacts to changes in humidity and air temperature. This is completely natural and applies to all wood materials, including OSB. Therefore, so that OSB does not lead, from every edge you need to leave a gap of 3 mm.
Now let’s talk about the fastener card. This is a phrase. Just a nice way to tell how to hammer in nails. Note that I said “nails” for a reason. For fixing OSB boards during exterior cladding, nails should be used, not self-tapping screws. This is due precisely to the fact that nails better tolerate the “walking” of OSB.
In general, self-tapping screws can be used for interior decoration. I just do not recommend using self-tapping screws for drywall, because they are not considered reliable enough.
So, OSB needs to be nailed along the edge every 15 cm.And after 30 cm into the intermediate frame racks (which were not on the edge, but inside the sheet).
Such a number of nails may seem excessive to someone, but do not forget that when we fix OSB, our goal is not only to prevent OSB from falling off under its own weight, we also need to stiffen the entire structure so that the house can withstand a hurricane or an earthquake.
Nails should be at least 2.5 times longer than the OSB thickness. Also, do not nail them closer than 1 cm from the edge of the plate.
Interesting fact: in the vertical position, the OSB board can withstand more loads than in the horizontal position. This is due to the specific direction of the fibers of the material from which the OSB boards are made.
When you nail the OSB to the frame, always move from one corner further along the perimeter of the slab. In no case you cannot first nail the plate in the corners, and then hammer in the rest of the nails.
And one last tip for today. When OSB boards are brought to your site, they will need to be protected from moisture. To do this, put pieces of wood under the plates, and on top. Film, but only in such a way as not to interfere with the free circulation of air.
This not only keeps the OSB dry, but also stabilizes the wood and adapts it to the humidity in your building site.
The most suitable for protecting wood (and OSB) from moisture is the so-called yacht varnish on a urethane-alkyd or alkyd-urethane base. Some of the popular brands:
- Tikkurila UNIKA SUPER (Finland). This brand is leading in resistance to environmental influences, immunity to ultraviolet radiation and temperature changes.
- Marshall protex (Turkey). Creates a plastic surface film.
- Marshall Protex Yat Vernik. Possesses increased wear and moisture resistance.
- PARADE (Russia). Keeps fresh for a long time.
- Belinka Yacht (Russia). Has dirt and water repellent properties, emphasizes the texture of wood materials.
- Antiseptic varnish for wood Drevolak on an acrylic basis with the addition of wax (Russia). Along with antiseptic and antibacterial action, it successfully protects wood from moisture.
The cheapest treatment option is water-repellent, colorless impregnation. There are no special solutions for OSB. Any wood product can be used, except water-based products. Examples of such formulations:
- Elcon wood preservative-impregnation, silicone-based. Designed for long-term protection of wooden structures from weathering, decay, mold. Scope: for indoor and outdoor use. Forms a water-repellent film, non-toxic, allows the tree to breathe.
- Innovative domestic hydrophobizing composition NEOGARD-Derevo-40 based on organosilicon oligomers. Designed to impart water-repellent properties to products made of wood and materials based on it: plywood, chipboard, fiberboard. Water absorption for chipboard is reduced by 15-25 times. Obviously, it works for OSB too. Does not change the natural color of the material, the protective properties remain for at least 5 years.
OSB (OSB): how to treat against moisture
Oriented strand board (OSB), which is used inside a dry room, does not need any additional protection from moisture. In the worst conditions, the outer cladding of the house is made of this slab. Over time, it darkens not only from rains, but also from solar ultraviolet radiation. Of course, it is possible to close the slabs with siding or blockhouse, but this is associated with high costs. How to process OSB (OSB) board from moisture is not an easy question. We will try to answer it.
Do you need additional processing?
The moisture resistance of oriented strand boards is characterized by the amount of swelling in thickness during the day. According to this parameter, according to the American PS 2 standard, European EN-300 and Russian GOST 10632-89, the plates are divided into 4 types (see table).
|Swelling in thickness in 24 hours,%|
Recall that only OSB-3 and OSB-4 slabs are allowed for the outer cladding of a building.
If the constructed structure still somehow gets off, then during the construction the OSB slabs lie on the construction site in bundles. Even after one rain, several top sheets swell almost one and a half times. They will remain so even after drying. The rest of the sheets swell at the ends. By the way, in order to avoid this, the ends of North American products are painted with a blood-red impregnation.
Among some builders, there is an opinion that OSB boards do not need additional processing, since they are already impregnated with resins, waxed, varnished. Experience shows that after 2-3 years their appearance loses its original freshness, they darken, in some places individual chips bulge out, the joints protrude sloppily.
Therefore, additional hydrophobic treatment will not be superfluous, especially if this is a facade of a residential building without any cladding. Consider how to process the OSB board from moisture.
Since OSB is a product of wood processing, the same paints and varnishes (LKM) can be used for them:
- Oil paints. Due to the presence of polymer resins in the OSB, varnish-based paints do not always fit well on the surface to be painted. For better adhesion to the substrate, it is recommended to make two priming with an intermediate putty before painting. Despite this, oil-based paints and varnishes under the influence of ultraviolet radiation, temperature extremes and atmospheric precipitation are prone to fading, cracking, and even peeling. We can recommend a paint based on natural and modified oil PINOTEX WOOD OIL SPRAY, which has good resistance to external factors.
- Alkyd paints are better suited to chipboards, since they contain alkyd resin, as a product of the chemical interaction of natural oils with acids. Their adhesion is higher in comparison with oil paints, they dry faster and more successfully resist weathering.
- Acrylic compositions, being inexpensive and durable in operation, are distinguished by an optimal ratio of qualities and are most in demand for painting wood. In addition, they are available in a wide range of colors.
Attention: pre-treat a small surface in an inconspicuous place to make sure that the material does not swell under the influence of an aqueous acrylic suspension.
In conclusion, we can say that the question: how to treat OSB (OSB) board from moisture, is difficult to answer unequivocally. Firstly: it depends on whether you want to emphasize the texture of the board with a transparent solution or, conversely, apply a covering (opaque) coating. Secondly: from the financial capabilities and aesthetic views of the developer.
Oil, water, alkyd based varnishes
For a hydrophobic and decorative coating of the facade of a house or dacha sheathed with this material, you can choose the following types of clear varnishes:
- Alkyd. These products form the thinnest film on the surface to be painted, which reliably protects it from moisture. The advantages of this type of paintwork materials include availability, resistance to ultraviolet radiation and low temperatures. They dry quickly and do not emit substances hazardous to humans. The main disadvantages of alkyd varnish are a pungent smell and a tendency to catch fire. Its application requires special preparatory measures, otherwise the coating will begin to bubble and crack.
- Acrylic. Water-based paint and varnish materials. Acrylates are used as adhesive components in their production. After applying the varnish to the surface, moisture evaporates, forming a reliable polymer coating. Plates painted with this agent are resistant to precipitation, UV radiation and fire, as well as low temperatures.
- Oil. The basis of these varnishes is linseed oil. The color can be from straw yellow to dark brown. Oil varnishes show good water and light fastness and form a film that reflects light well. These paints and varnishes are environmentally friendly, affordable, easy to use, reliably protect the painted surface from the destructive influence of external factors.
What is OSB: composition and manufacturing technology of the board, material features
The abbreviation OSB (OSB) comes from the English phrase oriented strand board and is translated into Russian as oriented strand board. Many Russian masters call this material OSB (and this is a more correct name). The material is a sheet consisting of several layers, which is made from wood chips (thin chips) and gluing components of formaldehyde resins or polyurethane compounds with paraffin-wax impregnation.
The production of this building material includes the following stages:
- Preparation of raw materials for shavings. The bark is removed from the logs without signs of rot, the wood is steamed, the raw materials are dried and sorted.
- Resinification. An adhesive composition is added to the chips. Different manufacturers use different adhesive components, which are kept closely secret.
- Forming sheets from shavings. Orientation system places the elements of the adhesive mass in a certain direction.
- Pressing. Under the influence of high temperature and pressure, the workpiece solidifies.
- Finishing. The cooled down workpiece is cut into sectors. Manufacturer’s distinctive marks are applied to products, surfaces are polished, edges are processed.
This material is characterized by:
- High reliability;
- Excellent appearance of the slabs are similar to wood;
- Stability of production quality;
- Low weight and defect rate;
- Ease of installation and handling;
- High coefficient of deformation for fracture;
- Excellent fixing of fasteners;
- Resistance to damage by insects;
- Moisture resistance.
Glazing composition (azure)
Glazing compounds, or azure, are transparent or translucent substances that give the material the desired shade while maintaining its natural structure. They have an acrylic or alkyd base. The first type of paints and varnishes is suitable for indoor work, the second is used exclusively for painting external surfaces.
Water based paints
These paints have a low moisture resistance, so they should not be used for interior decoration in wet areas in kitchens and bathrooms. Highly eco-friendly water-based paints are ideal for painting in bedrooms and living rooms. The most popular brands are Tikkurila, Teknos, Sadolin. Manufacturers of most of these paints allow regular wet processing of the surfaces they painted.
If, when purchasing paint, we take into account that these boards mainly consist of wood raw materials, the choice will be obvious oil-based paintwork materials. Such brands as Colorey and Sintilor have proven themselves well. This type of dye composition adheres perfectly to the work surface, is available, and has minimal absorbency, which significantly reduces product consumption. They allow you to create a coating that is resistant to mechanical stress, so they are ideal for painting floors.
Alkyd based paints
Coloring compounds based on alkyd resins are the best choice for painting walls and floors covered with OSB. They allow you to create a strong and durable coating, but not too economical.
Finishing the house outside with OSB slab
OSB slabs are used to erect frame buildings or to sheathe wooden houses. They are distinguished by good indicators of insulation and strength, although such a material is not sufficiently moisture resistant. The raw material for the manufacture of OSB is non-working coniferous tree or wood processing waste. The OSB facade can be deformed by water. Nevertheless, it favorably stands out for its environmental friendliness, practicality, easy processing and installation.
Construction experts advise using the OSB 4 or OSB 3 slab to cover the outside of the house, but the second option is considered less preferable. It is possible to sheathe the house outside the OSB of the third group, but it does not have special protection against moisture, therefore it must be additionally processed. OSB 4 is significantly more expensive, therefore, exterior decoration of a house made of OSB slabs is not performed very often when erecting economical buildings.
Since the basis of the OSB board is pressed shavings, smallpox for outdoor decoration can be processed with any paint compositions that are suitable for wood material. The limitations are determined solely by aesthetic features. In particular, there is no need to choose transparent varnishes or glazes. The chip texture is not endowed with special beauty, so it does not need to be displayed.
In addition to painting OSB plates, facade plaster is also suitable. Facade plastering technology is described in detail in the corresponding article, it will not have any peculiarities if the base of the wet facade is an OSB slab. You can perform plastering with or without insulation. Pay attention to the primer, it increases the adhesion of the substrate, i.E. The plaster composition better lays down and is fixed. In this article, we’ll talk in detail about how to paint smallpox on the facade.
You can read more about the characteristics and properties of OSB boards here.
How to paint the OSB slab correctly
The outside paint for OSB boards can be unevenly done. Therefore, it is important to know the features when performing painting work on a particle board.
Before painting the edges of the slab, sand the corners by rounding them a little. Otherwise, the surface will become unevenly colored. If the OSB texture is broken, then you will need to putty the entire slab before starting to paint the surface.
Primer application is considered a mandatory procedure. It makes the coating smoother and improves the adhesion of the paint to the wood. As a result, the period of exploitation of the decorative finish is extended.
OSB boards should be painted in two layers, and sometimes three or four colors are required. This is caused not only by the need to protect the OSB board from the outside from negative external factors, but also with aesthetics. Chips of building material are visible through a thin layer of paint, negatively affecting the facade.
To extend the life of the decorative finish and the facade, it is necessary to use anti-septic protection. This does not apply to OSB 4, since during manufacturing it is processed with all the necessary impregnations.
Examples of the selection of paint and primer. Stamps
In order not to carry out experiments, wondering how to paint the OSB plate outside and with which primer the paint is combined, it is easier to opt for those options that have already been tested and really work when finishing is done. This will save you time and money, and ensure durability.
Good results are obtained by combining a primer called Aqua Primer-3130 with a paint called Aquatop-2920 04. For a dense and high-quality decorative finish, only 2 layers of paint are required. The result is a smooth, waterproof surface with high UV protection. You can use detergents for cleaning later.
There is also a more economical way to successfully match colors. Namely, a primer called Teknol-2881 together with a paint called Nordica Eco-3330. Such a combination in its own parameters is not much different from the previous one, but it is not very well able to withstand the negative effects of household chemicals.
How to paint an OSB slab for exterior decoration on the facade of a house
When the building material from which the walls are made is oriented strand board (OSB or OSB boards), the question arises about the method of finishing. Facing of OSB slabs can be made with decorative natural or artificial stone, siding or corrugated board. But the enamel surface is more affordable and easier to execute. It is worth choosing how to paint the OSB slab on the facade of the house, master the technology and you can start finishing.
Which paint to choose
Before deciding how exactly to paint the OSB plate outside, you need to choose a suitable paint and varnish product. OSB is made of wood, so experts advise using paint for wood coatings. over, it is necessary to select only the one that is intended directly for facade work.
You can consider the most popular types of paints than you can cover the OSB plate on the street:
- Acrylic paint. The best option than painting the osb plate, both for its price and for the duration of operation. Quite unassuming paint, it is easy to apply, it is resistant to different climatic conditions. The variety of colors that are created thanks to color schemes is considered an obvious advantage of this type of painting.
- Oil paint. Painting OSB slabs with oil paint is being done in an increasingly less common way due to a significant number of disadvantages. It is quite toxic, keeps drips and dries for a long time. The duration of the preservation of such a surface is poor under the influence of sunlight and time, it is subject to fading and peeling. The cost of such paint is above average.
- Latex paint. It is the most expensive material, but also the most attractive. The latex surface is distinguished by its own density and strength and is reliably protected from impact, scratches and climatic factors. The coating stretches easily during various deformations of the base. Such paint is considered completely impervious to moisture, which is by no means always good. This is due to the fact that for a long and normal operation, wooden boards need to breathe.
- Alkyd enamel. The main positive aspects of this option are the favorable cost, resistance to sun rays and low temperature conditions (up to minus thirty degrees). The enamel dries quickly enough (within ten hours). At the same time, the enamel is highly flammable and endowed with a sharp and not very pleasant odor.
In order to paint the OSB facades, varnish is also used, which is intended for external work. It must certainly contain inhibitors that prevent the negative effects of ultraviolet rays.
Painting osb plates step by step
It is necessary to correctly observe the technology that allows you to effectively paint OSB, namely, one by one, perform the following actions:
- Make the filling of interpanel joints using a sealant, in particular acrylic.
- Thoroughly clean and prime the board cover.
- When paint and primer are applied, it is important to pay special attention to the ends, since they are considered the most vulnerable point of sheet building material.
- The edges of the OSB must be painted to visible rounding of all sharp corners.
Step 1 sanding
Grinding the surface is necessary only to smooth and hide the texture of the OSB board, as well as in the case of coating the surface with stains. This is best done with a grinder. To make the surface uniform, it will have to be carefully sanded. Especially deep grinding will have to be applied to plates of OSB-3 and OSB-4 brands, since it is necessary to completely remove the protective coating from varnish and wax.
Step 2 filling in the unevenness with putty
An oil-glue putty is used to seal various depressions. It fills in voids and traces of screws. After that, the plates are additionally sanded. It is not necessary to putty the seams and joints on the border of the slabs, you still will not be able to completely mask them. After painting, the seams will still be visible. Better to beat these mowing lines with decorative strips and correctly arrange the sheets of material so that there are no chaotic joints.
Important! When choosing a material, try to select plates where there are no particles of bark or it is minimal. During use, the bark often flakes off and spoils the appearance of the panels. The paint lays down worse, then you have to repeat the entire staining process. If the OSB plate is to be painted outside, this is especially noticeable because under the influence of ultraviolet radiation, the delamination process goes faster.
Preparation of OSB boards for painting
The better you prepare the OSB sheets for painting, the better the paint will be, the more resistant the coating will be. It is not advised to paint OSB panels before installation, because you still have to adjust the joints, grind irregularities. It is better to paint the already prepared wall.
Next, we will consider the recommended procedure for preparing the surface of the OSB board for painting.
What features should be considered when choosing paint for OSB
When choosing a paintwork for OSB, it is necessary to take into account certain features of this material.
How to paint an OSB plate the right choice of paint for exterior and interior work
Oriented strand board (OSB or OSB in a foreign manner) is a modern, very popular and affordable material for the construction of lightweight structures and buildings. It is convenient to mount it. Slightly uneven, textured surface gives room to the imagination and does not limit the possibilities for finishing. In order for surfaces made of OSB to serve for a long time, they must be protected from the negative effects of environmental factors.
One of the ways to protect OSB is to paint it. Next, we will tell you how to paint the OSB board, how to apply paint or varnish correctly, how to process the joints and prepare the surface for painting.
Adhesion of paint and varnish coatings and OSB boards
Some paints adhere very poorly to the surface of the OSB board due to poor adhesion between materials. This happens because OSB boards are initially impregnated with resins and poorly absorb paint. It is not recommended to use water-based paint and other formulations on a water-soluble basis for OSB coloring. It is necessary to give preference to acrylic or other polymer-based compounds.
What paint to choose for interior work?
You can paint with any material, given its characteristics. Since OSB boards are glued with resins and polymers, it is better to use organic-soluble pigments for coloring for maximum adhesion of paint and board when pigments penetrate into the structure of the panel:
- Coating with oil paints is considered the best option due to their high viscosity and low absorption into the board. The paint dries for a long time, but provides a high-quality and reliable protective layer.
- Coating with alkyd enamels or special alkyd paints for wood panels guarantees a long service life due to deep penetration into the structure of the material. In this case, you can refuse to varnish on top of the paint. This allows you to reduce finishing costs.
- You can use an acrylic water-dispersed composition, but then the board may swell from exposure to liquid.
If there is no need to close the texture, then impregnations are used, for example, Valtti Color Satin from Tikkurila. These products create a toning protective film with a semi-gloss or matte texture.
Zinga Electrically Conductive Metallic Paint can be used for decoration if the substrate is carefully prepared. To protect the panel from fire, they use antipyretics developed for wooden coatings: Vuprotek, SPAS and their analogues.
Outside, OSB can be painted with alkyd, acrylic, oil and latex paints. OSB finish the facade, install internal partitions and floor covering. For the topcoat, paints are used as the most affordable and inexpensive way of decorative cladding.
How to paint OSB
OSB boards (OSB) consist of a composite material made of crushed wood chips, glued together with various resins, adhesives and polymers. To protect the OSB board from moisture, it is impregnated with a compound that repels water or is painted.
OSB boards come with a different chemical composition of impregnations, fillers and protective coatings, so they are of 4 types:
- OSB 1 withstands minimum humidity in dry rooms, since there is practically no moisture-proof component in the boards;
- OSB 2 withstands average indoor humidity;
- OSB 3 withstands high indoor background humidity and occasional wetting;
- OSB 4 withstands high humidity inside and outside buildings.
It consists of a resin cooked from a mixture of acids and vegetable oil. A thin but strong film will protect the surface from moisture after the alkyd paint has dried.
Sandpaper is used to carefully sand the OSB board in order to mask the recognizable texture and exclude the penetration of the primer and paint into it.
It’s important to know. OSB-3 plates should be deeply and thoroughly sanded to remove the outer wax-varnish coating.
Why do you need to paint slabs?
Coating OSB boards with paints and varnishes has its advantages:
- Paint or varnish provide additional protection against moisture. Water will not be able to penetrate into the structure of the slab, no deformation will occur inside and on the surface of the OSB.
- Modern paints mask the texture of the slabs, so large chips are almost invisible.
- Painting is less time consuming than decorative paneling and costs less.
It’s important to know. They paint OSB, and then varnish only for interior work. Outside, slabs are protected by more serious methods due to significant climatic influences.