Last week, as part of the HOMI Moscow interior exhibition, designer Elena Tikhonova(MARCHI graduate, head of the Cameleon interiors design bureau) told how to use the features of plywood and MDF for the benefit of the interior, as well as whether living near these materials is really dangerous for health.
Plywood
Plywood is made from thin veneers, the layers of which are pressed and glued so that the fibers of each layer are perpendicular to the fibers of the previous one. This technology allows forming sheets of any size and thickness. They are durable and flexible at the same time, they are easily attached in a variety of ways (glue, self-tapping screws, nails) and well accept any finishing coatings.
Due to the fact that plywood sheets can be large in size, they are very popular in Europe for decorating walls and other surfaces. "Plywood" interiors are minimalistic and cozy.
As a rule, plywood is not tinted or painted, since its beauty lies in the pattern on the surface and on the cut. However, the panels can be stained. They can be attached so that the fibers are parallel, or you can make accent squares with a perpendicular pattern.
The wall in the photo below is a real art object. The sheets are placed end-to-end to the viewer and polished. The result was a three-dimensional construction with an emphasis on a beautiful cut of plywood.
In this and similar works, the relief on the end of the litas looks very impressive.
Plywood is much cheaper than veneer or solid wood, but, like them, it allows you to bring a real wood texture into the interior. You can play, for example, on the contrast between cold white walls and rough wood.
The similarity or difference of textures, color accents allow you to zone the space, change its architecture.
In the photo below - the interior, reminiscent of a topographic map. Sheets of plywood are simply cut, sanded and laid on top of each other with some beating. Making a table or shelves using this technique is easy even on your own.
In the children's room, plywood is rare, but also found.
Plywood can be used to create multifunctional and mobile furniture, such as shelving for a small room.
At the same time, being the only flexible wood material, it allows you to give the object a very different shape. Lamps, partitions, tables - many things made of plywood look very simple, but at the same time, due to its pattern, it is interesting.
Fashionable minimalistic decor is made from plywood: animal heads, small Christmas panels, letters.
MDF
MDF is an abbreviation derived from the term Medium density fibreboard, "medium density fibreboard". As the name implies, this material is made from individual wood fibers that are dried, pressed and sanded. Visually, MDF is much simpler than plywood, it does not please with excellent textures and flexibility, but it is very good for cutting and working with relief.
“For us, this material is quite new, it was mastered only in 1997, and now it is mainly used for furniture,” says Elena. “Unlike living wood, which has the ability to “play,” MDF is more stable and resistant to environmental influences, which is why it is possible to make durable furniture from it.”
The first option for using MDF is to simply make shelves, a cabinet, or whatever, and cover the thing with a finish.
The second option is wall panels. Popular in office spaces, with the right approach, they can also look good in a living space. You can add stone, lighting, ceramic layers to them.
The third option for working with MDF is to make a through thread. Such sheets can be used as a screen for a heating battery, a screen separating one area of the room from another, or a carved panel behind which decorative lighting is hidden.
Finally, the fourth way to process MDF is relief carving and the creation of 3D panels. They can decorate the entire wall, or, if you want to minimize installation difficulties, make an accent fragment from several sheets, arranging them with a small step. It is important to remember that in order for the panels to play, it is necessary to take into account the direction of the light.
And, finally, another option for interior design using MDF is to cut out plates of different sizes from the plates and lay them out on the wall.
Dangerous or not?
Although recycled wood materials are practical, inexpensive and even aesthetic in their own way, we tend to prefer solid wood over them. It's all about the bad reputation: each of us has heard at least once that such materials emit formaldehyde and other compounds that are not the most healthy for health.
Speaking about plywood, Elena admits that she has not yet finally decided for herself the question of the benefits and harms of this material.
“We see how actively foreign design bureaus use plywood. We have one big problem: plywood is glued together with adhesives that are of poorer quality. Depending on the release of harmful substances, plywood can be labeled from E0 to E3, and we have the best - E2. So it is better not to use our plywood in nurseries, bedrooms and other rooms where you spend a lot of time. It is better suited for terraces, outdoor and semi-street spaces where you don’t visit as often and which are well ventilated.”
The best thing, Elena notes, is to order plywood in Europe: judging by how often and boldly foreign designers use it, they have fairly safe options. You can look for production using more expensive adhesives, and with us. Unfortunately, all these options will negate one of the main advantages of plywood - its cheapness.
But MDF, the designer is sure, can be used anytime and anywhere: “Of all materials that are not solid wood, MDF is the safest and most convenient. It is produced without the use of chemicals, so the question of harm depends on the finish.
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Of all the finishes in use today, plywood finishes are rightfully considered classic. More and more new types of cladding are constantly appearing on the modern market, but despite this, home and professional craftsmen still widely use plywood, both for exterior decoration and for cladding or arranging the base indoors. In this article, from the point of view of practice, I will tell you what plywood is, how to mount it inside the house, as well as about all the subtleties associated with this process.
What to look for when choosing a material
Facing the house in general and the interior decoration of housing in particular is a responsible occupation that does not tolerate negligence. After all, you have to look at these walls, floor and ceiling for more than one year.
Plus, not every finishing plywood is suitable for housing. And in case of a mistake, instead of the desired environmental cleanliness, you risk getting a finish, roughly speaking, “stuffed” with carcinogens.
For those who want to know as much as possible about the types, purpose and other exact parameters of plywood as such, I can advise GOST 3916.1 - 96. It has 2 editions, one is responsible for hardwood material, the other for softwood plywood.
At the moment, these standards are considered fundamental. But keep in mind, this information is more intended for professionals.
What you need to know about labeling
As a finishing and partly building material, plywood has been actively used since the end of the 19th century. Naturally, over such a long period, a lot of brands and varieties have appeared. And it is quite easy for a simple layman to “get lost” in these wilds.
In this regard, I will not talk about narrow professional areas, those who are interested in such areas, let them study GOST. And for the general public and home craftsmen, it is enough to navigate the four most common brands:
- At least a third of the entire market is traditionally occupied by the brand "FK". This plywood is used for interior walls, floors and ceilings. It is made on the basis of carbamide compounds and is considered perhaps the most environmentally friendly. According to historians, it was with this brand that all production began. For dry living spaces, this is the best option;
The instruction for the brand "FK" positions this material as waterproof, but you should not take everything so literally. I once stepped on this rake - it turns out that there is simply moisture-resistant plywood and sheets with increased moisture resistance. So for outdoor work, as well as for facing wet rooms, such as a bath or toilet, the brand "FK" is not suitable. It needs other material, but first things first.
- The FSF brand just has increased moisture resistance. But it has very serious limitations. Such sheets are glued together with phenol-formaldehyde compounds, and recently, all over the world, phenols in any form are strictly prohibited from being used in residential premises, as they are recognized as powerful carcinogens. But for exterior decoration "FSF" fits perfectly;
- For residential wet rooms, for example, for finishing a bath or a bathroom, the FB brand is the best fit.. It is made on the basis of bakelite resins and will not delaminate, even if you water it every day. But the price of such a product is somewhat higher. By the way, it is from such plywood that craftsmen make boats, it is also used for lining marine yachts;
- For "home-made" people who are fond of furniture production, there is a brand "FOF" on the market. It is sold both laminated and blank. Finishing the walls inside the house with FOF plywood is acceptable, but often it doesn’t go further than arranging a kitchen apron or ceiling in the kitchen, since the price for these sheets is much higher than, for example, for FC, and with proper processing, it’s normal "FC" fully withstands kitchen loads.
If you need beautiful and safe
In addition to the type of plywood sheet, modern marking provides for two more important parameters - this is the safety class and sheet grade. With safety, everything seems to be clear, and the grade is responsible for the appearance of the material and the permissible number of defects on the "shirt" of the plywood sheet.
According to domestic SNiPs, there have always been 4 material safety classes, but after foreign products entered our market, these standards were revised and now there are 5 such classes. They can be found in the marking by the letter “E”.
- The highest degree of security for the class "Extra" Although the parameters for the class E-1 are approximately the same. Scrupulous owners are often interested in whether it is possible to use plywood for interior decoration of a nursery. So these two classes are just designed for such premises. If this marking is indicated in the certificate, then you are not afraid of any sanitation station;
- Sheets of class E-2 are also allowed to veneer residential premises. Often, it is this class that professional and home craftsmen prefer to use, since it is much cheaper than the previous one;
- Exterior cladding, as well as interior decoration of utility rooms and non-food warehouses, is carried out with sheets of class E-3;
- As for class -4, it is not used in finishing work. Such sheets, as a rule, go to non-food packaging or the arrangement of bulk foundations.
Grade is responsible for beauty. With the division into grades, things are about the same as with safety labeling. That is, before there were 4 of them, and with the fall of the Iron Curtain it became 5:
- Variety "Extra" is the perfect cover. It shouldn't have any flaws at all. It is not difficult to guess that the cost of such a product is the highest;
- The first grade is not far from the previous version. The only thing that is allowed in it is 1 - 2 fragments of a healthy change in the color of the shirt;
- The second grade in finishing is considered the most demanded. Color change is not regulated here, plus the presence of 2 - 3 healthy ingrown knots is allowed. In my experience, people choose this variety not only for the more affordable price, although this is also important. The reasonable presence of knots gives the lining a natural naturalness. For example, finishing the ceiling in a wooden house with second-grade plywood does not spoil the surroundings of a wooden frame;
- The third grade is not yet a marriage, but it is already difficult to call it facing. No one here pays attention to the change in the color of the shirt. There can also be as many ingrown knots as you like. The only restriction is on dark falling knots, they should be no more than 3 - 4 per 1m²;
- There is also a 4th grade, but it does not apply to the topic of our article, since it is used only for technical purposes and there are no restrictions, there are no shirts at all in appearance.
Important: in professional terminology, if the plywood thickness does not exceed 12 mm, then it is called a sheet. All material whose thickness exceeds 12 mm is already referred to as plywood board.
Plywood finishing technique
It is believed that in a wooden house plywood can be faced with almost any internal and external surface, but in block houses only the attic is finished in this way.
I don’t know who came up with such conventions, but let’s say my dacha is made of cinder block, and inside all the decoration is plywood. In those years, there was simply nothing of inexpensive and decent materials that could be assembled with your own hands.
And I know for sure that if the interior decoration of a block house with plywood is done correctly, then it will stand for an arbitrarily long time. At least in my dacha, plywood cladding has been standing since the late nineties and looks quite decent.
Floor arrangement
As you know, the floors in the house are experiencing the greatest load, respectively, and they need to be equipped in good conscience. Although there is nothing particularly difficult here.
Such a coating can be mounted on logs, this is the easiest. On loose insulation, such an installation is also called a dry screed. And on a concrete or floor slab.
In order for the floor to be sewn up with plywood sheets, the logs should be at a distance of no more than half a meter from each other. In this case, the width of the log itself starts from 50 mm.
As I said, this is the easiest and by the way, the most practical way to install the floor. After all, between the lags it is easiest to lay some kind of insulation. Yes, and any amateur can fasten plywood to a wooden beam.
If insulation is planned to be installed between the lags, then a ventilation gap of at least 10 mm must be left between the insulation and plywood. Otherwise, condensate may collect from the inside, and this, as you understand, is not desirable for wood.
Theoretically, the floor can be covered with thick plywood slabs in one layer, but in practice this approach is justified only if you mount the base under any finishing material, for example, laminate or parquet.
The coating will be much better if you lay plywood in 2 layers. So a floor assembled from 2 layers of 10 mm each can withstand much greater static and dynamic loads than a solid slab 20 mm thick.
The installation technique itself is not very complicated. It does not matter in one or two layers you will cover the floor, in any case, a compensating damper gap of 10 - 15 mm must be left around the perimeter. It is needed so that with the inevitable temperature and humidity fluctuations of the material, your floors do not swell.
Then you just take and fasten the sheets to the logs, before this was done with nails, now people have switched to self-tapping screws. But by and large, there is not much difference, because both nails and self-tapping screws on the floor have nowhere to go.
When mounting sheets in 2 layers, in no case should the joints of the lower and upper layers coincide. It is due to the shift between the sheets that the increased strength of the coating is ensured. Moreover, this law is valid for the arrangement of any multilayer coating.
The technology for installing a plywood floor on a loose heater or a dry screed is no more difficult than the previous version. As a rule, such floors are laid on leveled expanded clay. And the most difficult thing for a novice master is to properly level expanded clay.
Sheets are laid on top of such a base in 2 layers and fixed only to each other. Moreover, both layers are mounted simultaneously.
That is, they laid a sector of 3 - 4 sheets of the lower layer and immediately on it, with a shift, attached 2 - 3 sheets of the upper layer. And so on, until the whole room is closed. And don't forget the damper gap.
Mounting plywood on a concrete screed or floor slab is not much different from arranging a dry screed. The only serious requirement for such a floor is good concrete waterproofing.
According to the rules, it is desirable to do concrete waterproofing using modern roll materials. Such a “carpet” is soldered with a gas burner or, at worst, smeared with bituminous mastic.
But as far as I have come across, most craftsmen simply cover technical polyethylene in 2 layers on concrete. It's cheaper and faster, and the result is almost the same.
Concrete is a rather cold thing, plus it is quite difficult to bring it to zero, that is, to make a perfectly even coating, without the slightest drops and defects. Therefore, a layer of extruded polystyrene foam is now being covered over the concrete. If you feel sorry for the money for such a heater, then you can use foamed polyethylene, but the effect will be worse.
Then you just have to lay plywood sheets in 2 layers and, as usual, fasten them together with self-tapping screws or nails. Naturally, self-tapping screws must be selected so that they do not crawl out from the back of the flooring and do not break through the waterproofing.
Wall arrangement
Decorating the walls inside the house with plywood is a little easier task than arranging a plywood floor. It is best to take sheets that are equal in length or slightly higher than the height of the ceiling. So you do not need to measure the joints and suffer with the layout of this "patchwork quilt".
In a wooden house, plywood can be sheathed directly along the walls, of course, if these walls are relatively even. Or at least the vertical is maintained along the upper points. Otherwise, you will have to mount a wooden crate.
Installing it is not difficult. When choosing planks for the crate, and the width should not be less than 25 mm, otherwise they may crack when driving nails.
Although if it is not planned to install wall insulation, I use a planed board with a section of 20x50 mm. It is easier to insert wedges under it, if necessary, and it is more convenient to mount sheets on such a wide platform.
It doesn't matter which plane you equip, floor, wall or ceiling. Plywood sheets cannot be fastened rigidly end-to-end. Be sure to leave a couple of millimeters of damper gap between them.
The interior decoration of a block house with plywood has its own peculiarity. A vapor barrier membrane should be attached to the walls under the wooden crate. Keep in mind, not polyethylene, but a vapor barrier membrane, in which one side is vapor-permeable.
It must be mounted taking into account the direction of steam movement, and steam in any residential heated room moves in the direction from the inside to the street. All such membranes have a marking indicating the vapor permeable side, so look carefully.
A few words about ceiling installation
The installation of the ceiling itself is practically no different from the arrangement of the walls. In the same way, sheets are sewn on a flat wooden ceiling in a continuous layer. And the curvature of the ceilings can be quickly corrected with plywood mounted on a wooden crate.
In this case, it is more important than finishing the plywood ceiling. In general, finishing ceilings and finishing walls with plywood have one common problem. No matter how hard you try, the joints between the sheets need to be hidden.
And if the gaps between the sheets on the floor can be filled with colored sealants, then such a number will not work with the walls and ceiling. Here you will constantly have the feeling of an unfinished picture.
I saw a lot of experiments on this topic and came to the conclusion that the only correct solution would be to close the gaps between the sheets with decorative overlays. Previously, these were exclusively wooden planks with figured processing. Now there are pretty decent overlays made of plastic and MDF.
But when choosing how to finish plywood, you need to be careful. So if you have a second-class veneer front shirt, then no matter how you grind it, only curly wooden planks will fit a natural, somewhere even rough pattern with ingrown knots.
Plywood of the highest and first grade is quite another matter. After a good sanding, it can be covered with several layers of varnish and then you can decorate the joints of the sheets as you please. Both wooden planks and MDF or plastic are equally well suited here. The main thing is that everything should be linked with the main design line.
In some cases, it makes sense to spend money on laminated furniture sheets of the FOF brand. This will be cheaper than taking top-class plywood, additionally sanding it and covering it with several layers of varnish.
Briefly about paints and varnishes
Separately, I want to say about paints and varnishes. Since we are dealing with facing wood material, special paints are needed here. When it comes to topcoats for wood, acrylic formulations come to the fore.
The quality and durability of such paints is one of the highest. And most importantly, almost all acrylic compositions are water-dispersed.
This means that they are environmentally friendly and do not clog wood. Simply put, wood breathes. Although you need to be prepared for the fact that such paint is not cheap.
As for varnishes, according to my observations, the share of their use in plywood finishing now reaches 70%. The most affordable option for interior work is ordinary furniture varnish.
Although the market now offers a lot of other interesting compositions. For example, at my dacha, I covered plywood with urethane-alkyd varnish, this varnish is also called yacht varnish. Now a liter can of yacht varnish costs about 400 rubles.
On the other hand, an ordinary “FK” sheet, covered in three layers with yacht varnish, can be safely mounted not only in the kitchen, but also in services. The coating is of high quality and durable, but such a varnish completely clogs the wood, so choose.
Subtleties to keep in mind
As you can see, the finishing technology, in general, is not complicated. But if you have not come across such works before, then relying only on your intuition will be very reckless, because, as in any work, there are a lot of small nuances and subtleties.
In cases where plywood is the final face covering, it is almost always varnished or at least painted. And here, if you start applying the composition to the sheet shirt without preparation, then you will not be able to achieve decent quality. The veneer must first be sanded with sandpaper.
Then it is advisable to walk on it with soil or apply the first starting layer. When the composition dries, a barely noticeable pile will rise on the wood. To remove it, you will need to sand the sheet again with thin emery. And only after that you can apply all the other layers of the coating.
Regarding grinding, there is one more small recommendation - sheets are sold in three types: polished only on the front side “Sh1”, sanded on both sides “Sh2” and not polished “NSh”.
So, if you want to get a really high-quality coating, you should not trust factory grinding. Even when the marking indicates that the surface is polished, in any case, it should be finished with your own hands using fine emery.
Now let's talk about cutting. The most problematic place of the plywood sheet has always been the corners. And so that they do not crumble during cutting, you must first cut all the markings that are applied across the fibers of the front side, and then only go to the lines drawn along the fibers.
Another important point is the selection of a tool for cutting plywood. If you have a hand saw for wood or a band saw, then you need to cut from the front side. But if you have a circular or contour saw in your arsenal, then they cut plywood from the wrong side.
When dissolving a sheet at a sawmill or working with a hand-held circular saw, the maximum speed should be set on it. But the sheet must be submitted as slowly as possible. Otherwise, you run the risk of crumbling the edges of the top or bottom shirt.
Plywood refers to wood materials with increased strength. Accordingly, the tooth of a hacksaw or circular saw is selected smaller. The cut, of course, will not be so fast, but it will be clean.
If you are working with a powerful electric saw, then during the cut you need to press on it lightly so that you feel a slight return, in which case the likelihood of a crease will be much lower.
To ensure a smooth cut, without splitting the edge of the shirt and creating creases, there are a couple of little tricks. The first trick is to pre-stick masking or simple stationery tape on the cut line.
And the second trick, so that the bottom shirt remains intact, another, roughly speaking, ownerless plywood sheet or wooden plank is placed under the work sheet.
True, not every novice master has ownerless material that he does not mind adding, but still keep in mind. By the way, clean holes in plywood are drilled according to the same principle, using a lining.
Since we have already begun to talk about the rules for cutting plywood, it would be useful to recall: if you value your eyes, hands and your health in general, in no case use a grinder to cut wood in general and plywood in particular. For those who doubt, I can recommend typing the appropriate query in the search and see what it leads to.
It is far from always that novice masters get an even cut. Don't worry, small irregularities in the cut can be corrected with a planer by lightly trimming the edge. But you need to plan in the direction from the corners to the middle, otherwise the corners may crumble.
As a rule, plywood cladding is fastened with nails or self-tapping screws. So, the length of the nails should be about 2.5 - 3 times greater than the thickness of the sheet. In other words, for a sheet of 10 mm, nails of about 30 mm are selected. And when a sheet 18 mm thick is attached, nails 47 - 55 mm are taken for it.
When you are sheathing walls or ceilings, nails should be hammered along the edge in increments of 100 - 200 mm. In the middle of the sheet, the step can be made wider than 200 - 300 mm. When arranging floors, such a tight fixation interval is not needed, here 200 - 300 mm is enough at the edges, and in the center the step can reach up to half a meter. And yet, a nail or self-tapping screw cannot be driven closer than 10 - 15 mm from the edge of the sheet.
Conclusion
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Technology
The production technology of laminated plywood can be conditionally divided into two stages
- production of PSF as such;
- plywood lamination.
Production of plywood FSF
Making plywood is a fairly simple process if you don't go into details, and extremely complex if you go into it. We will try to describe it in general terms.
Plywood is made from peeled veneer, which in turn is obtained from pieces of tree trunks (churaks). Churaks are steamed in hot water until the lignin softens and then placed in a shelling machine. The peeling knife cuts off a thin strip of veneer from the rotating block, which is then straightened, cut and dried.
The resulting veneer is glued with a resin-based adhesive. For the manufacture of FSF plywood, which is used for lamination, phenol-formaldehyde resins are used. Such resins are a product of the polycondensation of phenol and formaldehyde. Plywood mills usually do not have their own resin production and purchase resins from chemical companies.
So, the resin-based adhesive is applied to veneer sheets, which are stacked on top of each other and then placed in a press. In a press, under the influence of high temperature and pressure, veneer sheets are glued together, and a multilayer wood board is obtained.
An essential point: the veneer is stacked not at random, but taking into account the direction of the fibers. Usually plywood consists of an odd number of layers of veneer. The central sheet is laid along the conditional axis, the next two on both sides of it - with fibers across the axis, the next - again perpendicular to the neighboring ones. This arrangement is necessary to achieve maximum tensile strength in all directions and compensate for internal stresses. Both are extremely important for film faced plywood, which is commonly used in formwork and takes a lot of load.
The glued plywood is removed from the press, cooled, marked and packaged.
lamination
The most widespread lamination of plywood with phenol-formaldehyde and melamine films. Melamine film has less moisture resistance, but does not emit phenol and other harmful substances at room temperature. Phenol-formaldehyde resins are gradually destroyed, releasing both phenol and formaldehyde compounds, but such a film has a very high moisture resistance.
The difference in properties determines the difference in application: plywood laminated with phenol-formaldehyde film is used for formwork, and melamine-coated plywood is used as a material for finishing and furniture production (if we are talking about FK or FKM plywood).
Laminate applied to plywood is a sheet of thick paper impregnated with the appropriate composition. The surface of the plywood sheet is smeared with glue (the same phenol-formaldehyde or melamine-formaldehyde resins), after which a film is applied to it. The sheet is then placed in a hot press where the laminate is fully pressed against the veneer to form a single unit.
The laminate layer is a reliable barrier that protects the wood fibers from moisture, but it can penetrate through unprotected ends. The ends of the formwork plywood are coated with phenol-formaldehyde resin, which does not allow water to pass through. Furniture laminated plywood is subsequently cut anyway, and therefore its ends are not covered with anything.
Plywood is a well-known and widely used material. Its operational properties are well known to everyone who at least once engaged in self-repair of housing or furniture. From this article you will learn about the new qualities and characteristics of this material - finishing plywood.
Despite the well-established image of a technical construction material, plywood is becoming more and more popular for fine finishing and creating unique interiors, while maintaining its reliability and ease of processing. This became possible thanks to the creation of a new variety - finishing plywood.
Specifications
Finishing plywood consists of three layers - constructive, decorative and protective.
structural layer. This is a board formed by multilayer gluing of wood sheets. Such sheets with a thickness of 0.5 to 3 mm are called veneer, they are obtained by cutting timber (logs). Then the individual sheets are glued with epoxy adhesives (resin based), alternating the direction of the fibers.
Plywood production video
decorative layer. End sheets of veneer on one or both sides, made of valuable or simply beautiful woods. It can be, among other things, selected (without defects) veneer of the material of the structural part. In most cases, it is made from oak, hornbeam, beech and other hard and resistant species. The decor may include structuring - structure imitation furrows, staining, tinting, branding (burning out a pattern, letters).
protective layer. It is necessary for protection against pollution, attrition and moisture. It is applied in two ways, depending on the purpose of the product.
Lacquering. It is used to protect the finishing layer of natural wood. Alkyd and water-soluble (yacht) varnishes are used for coating. Products are often supplied unsanded or clean-sanded for fitting, finishing and varnishing on site. This option is popular when creating unique interiors and decorating fireplaces, cabinets, vertical and horizontal panels.
Lamination. There are two types - constructive and decorative:
- Constructive. A polymer layer of 1-3 mm is glued to the structural base (“rough plywood”) by the factory thermal method, or rather, welded. It serves as a finish and protection at the same time, and it allows you to apply additional finishing layers - tiles, plastic, etc. The polymer itself gives strength and durability to the plywood board.
- Decorative. Sheets are pasted over with a moisture-proof film or thin polymer panels on heat-shrinkable glue. Easily "turns" structural plywood into any kind of wood. Scope - finishing panels and shields, consumer furniture.
A subspecies of laminated plywood is formwork plywood, it has an E4 safety class and is used only for concrete formwork.
Classification of finishing plywood by raw material
According to the type of raw material used, finishing plywood is divided into two types with generic names:
- "Birch". For production, birch, poplar and other “white” hardwood veneers are used. Such wood has greater structural strength than softwood, but is more prone to shrinkage and moisture saturation, soaking. Used as a base for parquet boards, furniture boards, interior decoration. "Birch" finishing plywood is widely used in the manufacture of furniture.
- "Coniferous". Layers are created from wood of any coniferous species. A distinctive feature is the saturation of the fibers with natural resin. This gives better (than birch) resistance to moisture, shrinkage and corrosion. Allows you to reduce the amount of glue. It is used for exterior decoration and cladding of rooms with a difference in humidity - vestibules, verandas.
- "Mixed". Both grades of raw materials are used - properties are averaged, and technical indicators are achieved by additives in glue and impregnations.
Scope and safety class
Safety is the main requirement of the modern building materials market. The safety class is denoted by the letter E and a number characterizing the emission of harmful substances. For plywood, these are phenol, formaldehyde, phenol-formaldehyde and ammonia - decomposition products of epoxy glue for layers.
In the European classification, there are 5 safety classes for the emission of harmful substances - from E4 to E1 and Super E. For interior finishing materials, only the last two classes are applicable - E1 and Super E. This indicator limits and specifies the scope of products from finishing and structural plywood:
- Class Super E and E1. Children's and hospital furniture, decoration of premises associated with a long stay of children and patients.
- Class from E1 to E2. For residential buildings, animal kennels and food stores. Part of the construction of the shields of the walls of the house, floors, roofs, ceilings, partitions.
- Class from E2 to E3. For public needs. Furniture of public buildings, sports equipment, MAF *.
- Class from E3 to E4. For industrial needs. It is used to make technical furniture (workbenches), industrial parts, elements of mobile vehicles and machine tools, containers and packaging.
* MAF - small architectural forms. Benches, sandboxes, slides, gazebos, etc.
Separately, it is worth highlighting the veneer, which is part of the plywood, but does not have a place in the certification for toxins, because it consists of pure wood. Read more about security classes in our article.
Finishing plywood products
Sheet. All types described in the article can be purchased in the form of an uncut sheet. Area dimensions:
- 1525x1525 mm (2.32 m 2)
- 2440x1220 mm (2.97 m 2)
- 2500x1250 mm (3.125 m 2)
- 2800x2070 mm (5.796 m2)
Sheet thickness:
- 4-8 mm (1525x1525 mm)
- 8-16 mm (1525x1525 mm, 2440x1220 mm)
- 16-32 mm (any size is available)
- over 32mm (any size to order)
Parquet board. The most common joinery made of finishing plywood. Reliable and durable flooring, similar to parquet. Many times cheaper than a natural prototype due to the replacement of solid wood with plywood. It is produced in the form of finished panels (width 100-250 mm, length 1200-1800 mm) with locks around the perimeter. Completely ready for installation and operation.
Furniture. Kitchen and cabinet furniture imitating natural wood. Usually these are the facades of kitchen and cabinet sets, decorative inserts. Recreation or imitation of antique furniture, fireplaces. Usually this is a "custom" work - cutting is done in the workshop. Finishing - in the shop or on site.
Wall panels. Elite decoration of antique or modern wooden interiors, walls, ceilings. When covering large areas, plywood sheets of a given size end up with a lock like on a parquet board.
Like any composite material, finishing plywood helps to achieve several goals. First of all, this is saving personal funds, because products made from it are much cheaper than those made from living wood, and they look completely indistinguishable. In such products, up to 80% of natural material is replaced. Secondly, such products are much more resistant to moisture and are uninteresting to insects. Thirdly, the colossal savings of natural resources - valuable and rare species of wood, because it is precisely the careful attitude to nature that makes a person - a Man.
Among the methods used in the interior decoration of premises is plywood cladding. Plywood is made from veneer of different types of wood, more often it is birch or coniferous (pine, larch). Thin (up to 1.5 mm) veneer is laid in layers, in each of which the direction of the fibers is perpendicular to the previous one, and glued together using synthetic resin compositions. 
When finishing work, there may be such a need as sheathe the walls with plywood. The ceiling of the room can also be lined with plywood.
Plywood is also used in the manufacture of a clean floor when it is directly laid on logs standing on a wooden or reinforced concrete floor.
It is also used to form a new outer surface of old wooden plank floors, as well as concrete - over a cement-sand screed.
- Drill (screwdriver);
- Electric jigsaw;
- Sander;
- A hammer;
- Hacksaw;
- Plumb;
- Levels - water and bubble;
- Narrow spatula;
- Axe.
Preparation of surfaces for cladding
The types of plywood for walls, ceilings and floors that can be used in construction can be classified as follows.
Plywood is produced in different thicknesses - from 3 to 30 mm.
Its outer surface can be:
Alignment of walls with plywood, as well as ceilings, is most often performed with flexible plywood made of softwood with a thickness of 6 to 22 mm, for floors along logs - 30 mm. Standard sheet sizes are 1220 x 2440 and 1225 x 2500 mm.
The surfaces of the interior of structures and buildings that can be finished with plywood sheets are:
To determine the amount of the required material, the surface areas of walls, ceilings and floors (minus the areas of openings) to be lined are calculated and summarized. What happens is divided by the area of one sheet and multiplied by 20 ... 25% (margin for unforeseen circumstances). The calculation of the frame rails is carried out based on the known dimensions of their cross-section, the number of required plywood sheets. The calculation will be greatly simplified if you first draw a diagram of the layout of plywood and frame elements on a sheet of paper. 
When the work planes have a flat pre-smoothed surface (for example, they were previously covered with a layer of ordinary plaster), plywood sheets can be installed directly on the glue. In this case, it is necessary to provide for any devices that rigidly hold the sheet on a vertical or horizontal surface until the adhesive composition is completely set.
An easier way, suitable for any cladding surface, is to attach plywood to the ceiling and wall using a frame.
The simplest frame can be made from wooden slats with section dimensions of 100 x 25 for the perimeter (to which adjacent sheets will be attached vertically and horizontally, 2 per rail) and 50 x 25 mm for intermediate parts. If there is a need for thermal insulation, and mineral wool mats or foam panels are usually used as its quality, wooden frame elements should be taken 1 cm thicker. 
It is more convenient to assemble the frame from individual elements on a flat horizontal surface, after which it is rotated at an angle of 90 degrees, leveled and fixed on the desired wall, or also horizontally rises to the level of the existing ceiling and joins its bottom.
As fasteners when attaching the frame to wooden walls and ceilings, long screws are used, designed for wooden joints. The installed frame must fit snugly against the surface to be lined; wooden wedges and linings can be used to level it. During installation, for better adhesion to the surface, strongly protruding areas can be slightly leveled with an ax. 
Wall decoration with plywood
To install the frame on a brick or concrete surface, you can use perforated bending metal strips designed for metal frames for drywall.
Before use, the wooden frame elements, as well as the reverse (invisible) side of the plywood sheets, must be protected from fungus, decay, mold by impregnation with antiseptics, as well as compounds that prevent easy ignition.
Plywood sheets and a wooden frame are fastened together with screws, the pitch of which in the vertical and horizontal direction must exceed 400 mm.
When constructing a floor from a plywood sheet along the logs (additional floor-supporting beams laid on top of the supporting structures of the floor) with a step of no more than 400 mm, a wooden beam with a thickness of at least 60 mm and a width of 50 to 100 mm is used for their manufacture (to ensure fixing two adjacent sheets on one lag). The thickness of the sheet for such a floor should be 30 mm. 
After installation, plywood sheets are puttied and primed. There are many ways to finish the final surface of a plywood room. It can be either simple coloring or wallpapering of different types.
If for the purpose of a certain design of the room it is required to preserve the texture of wood, plywood can be ennobled with a variety of stains, tinting impregnations and coated with a colorless varnish.
In this case, it is better to close the seams between plywood sheets with wooden planks or mask with strips of a self-adhesive laminating film matched in color.
The benefits of plywood
Finishing walls and ceilings with plywood is especially good in a wooden country house. When choosing interior finishing work, plywood sheets are a worthy replacement for the more commonly used drywall. You can also use the combined method, where these two materials can be used together. It is known that drywall is very easily destroyed by impact. In places where it is critical, it should be replaced with plywood, which is practically devoid of this drawback. 
If you want to use the texture of natural wood when decorating the premises of the house, it is not recommended to use a varnish that gives a shiny finish, as the gloss reveals a large number of flaws in the finish, which are invisible on a matte surface. Interior plywood cladding is as simple as drywall cladding and is easy to do yourself.
