Which windows are better to install: plastic or wooden. Which windows are better: plastic or wooden? Reliability of plastic windows

Probably, each of us, when building a house, or when replacing dilapidated frames in an apartment, was faced with the problem of choosing windows - plastic or wooden? Warped and cracked, difficult to close, dusty between the cloudy openings of rattling glass, these construction elements dating back to Soviet times have become the subject of numerous ridicule and are an eyesore for caring family owners.

Why plastic windows?

In many ways, it was the stereotype formed from the past that contributed to the boom in construction know-how - plastic windows. More precisely, metal-plastic, because the frame is reinforced with metal from the inside for rigidity. Production of products began back in the 1960s in Europe. At first there were imported ones from Germany and Poland. Then production was established in our country.

Plastic quickly conquered the window market in Russia, standing out primarily for its insulation characteristics, tightness, durability, and aesthetics. And also the absence of constantly jamming vents and latches, as it is equipped with a convenient opening system in two (three) directions.

Competently and culturally structured service marketing also played a major role in activating demand for plastic windows. Manufacturers and suppliers of PVC windows immediately established service and maintenance, offering the buyer turnkey installation of products.

PVC – polyvinyl chloride – the main composition of the material.

It is enough to pay the purchase price - and there are no problems: delivery, replacement of old structures, installation, even cleaning and removal of construction waste.

Wooden windows could not boast of such attention to themselves.

Firstly, they were not included in the assortment at woodworking enterprises, so there were no significant changes in production technologies established back in Soviet times.

Secondly, manufacturing in the 90s was in the artisanal segment of the economy, and therefore there was a high percentage of defects. Moreover, it was difficult to legally punish such a manufacturer for dishonest work.

Thirdly, an inexperienced buyer had to both choose wooden frames and look for an installation specialist - again, from the above-mentioned “traditional craftsmen”.

And most importantly, the ease of use of PVC windows and their cleaning, compared to wooden ones, was undeniable.

Why wooden?

Few people know, but plastic windows in Europe have long lost ground to wooden windows. For example, today wood accounts for 60% of the European market. It is not without reason that in the EU countries a huge amount of appropriate tools and lines for the production of wooden windows are produced.

Therefore, in the 90s, manufacturers of plastic windows, in order not to lose sales, began to develop the markets of post-Soviet countries, offering tempting prices and service, the quality of which we mentioned above.

Gradually, thanks to thoughtful marketing and advertising, a stereotype was created for residents of the “scoop” that PVC windows are a symbol of wealth and prestige. At the same time, in Germany, Austria, France or Switzerland, on the contrary, wooden Euro-windows are a symbol of prosperity and respectability, being aesthetically attractive and environmentally friendly.

But also more expensive, because the manufacturing technology cannot be compared with the Soviet “ancestors”.

Previously, in the USSR, solid pine timber was used to make windows, which was economically beneficial, but caused the window frames to deform under the influence of humidity and temperature.

In Europe it is used wooden blank made of three-four-layer laminated veneer lumber. For production, pine (the inside of the timber), oak, ash, and Siberian larch are selected, but there are also production technologies from mahogany - meranti.

For example, light red meranti has characteristics similar to oak, slightly inferior in hardness.

Products made from beech and chestnut are classified as elite and expensive. There are almost none of them on the market, not so much because of the high cost, but because of the complexity of preparing the source material and processing. For example, the manufacture of an oak window is preceded by three years of drying of the blanks under certain conditions.

Manufacturers - especially small ones - replace the natural drying of wood with an electric dryer. This leads to the fact that the profiles may become covered with black spots.

Note that a compromise in terms of “price-quality” is windows made of expensive wood on the outside and a layer of pine on the inside.

The workpieces are processed and impregnated chemical compounds, improving moisture resistance, protecting against rotting, but at the same time not preventing the wood from “breathing”.

It is worth noting the diversity paint coatings for wooden windows. It is better to give preference to German, Finnish and Dutch paints, which preserve the properties of wood, improve the appearance of products, and emphasize the structure of wood (if “varnished”). Wide color and texture palette.

Differences between wooden and plastic windows: pros and cons

There are conflicting reviews both heard and on the Internet. But it is worth noting that most of them are initiated by interested parties, and therefore are subjective, speculative, and pursue the goal of “drowning” a competitor or promoting their product.

To objectively evaluate wooden and plastic windows, it is more correct to compare the advantages and disadvantages that have appeared during many years of operation. From the point of view of how these products have proven themselves in practice, common reviews and opinions are analyzed. So let's get started.

1. PVC windows are easy to use

Because of this quality, they have gained popularity in our country. But let us remember that plastic windows appeared in our country against the backdrop of a pitiful state in the production of similar wood products. Modern wooden ones have an elegant appearance, and the profile is in no way inferior to plastic ones in terms of convenience. In addition, partial repairs of wooden windows are provided; the color can be easily refreshed or changed.

2. Plastic windows have excellent tightness

But, unfortunately, they are even too tight, and poor ventilation leads to the formation of mold and moisture condensation. This is one of the main disadvantages of metal-plastic products. To avoid this problem, you must either buy windows with a built-in ventilation system, or purchase separately supply valve. Wooden ones are almost free of this drawback, because, as they say, they “breathe”. According to average data, a standard wooden frame passes through its pores about 2.5 cubic meters per day. air. Thus, wooden products help maintain optimal air consistency, since wood stabilizes the humidity regime better than other materials.

3. PVC windows have high thermal insulation

The question is controversial. Air chambers metal-plastic windows significantly reduce heat transfer. But the main merit in this is not so much the profiles as the double-glazed windows. And modern wooden frames are also equipped with high-quality one- or two-chamber packages (glasses connected along the contour, between which an air-filled space is formed). In addition, the wooden frame itself, due to its natural porous structure, has lower thermal conductivity than PVC, which is especially important in conditions of Siberian cold or Asian heat. The same quality of wood prevents, unlike plastic, the appearance of condensation on the doors.

4. Plastic is highly sound insulating

The statement is also controversial. As in the previous paragraph, everything depends on the quality of the double-glazed window and the number of glasses in it: the more, the more noise is delayed. But wood, thanks to its texture, is an excellent soundproofing material, not inferior to, or even superior to, plastic profiles.

5. Plastics are easy to care for and wash, even with the use of abrasives

It's right. Wooden products are more demanding when it comes to the use of detergent compositions, and especially do not tolerate abrasive ones. Without proper care, they age quite quickly and become unusable. But on the other hand, unlike metal-plastic wooden structures They do not have electrostatic properties - they do not attract dust - so they do not need to be washed as often as plastic ones. This is especially important in industrial or arid steppe areas.

6. PVC windows can withstand high humidity without problems

This is true. Even more: plastic is a hydrophobic substance (repels water). Unlike wooden competitors, plastic windows very well withstand even prolonged contact with moisture or the influence of precipitation. Modern technologies are not yet able to completely protect wood from destructive moisture, which is the main cause of rot and mold.

7. Metal-plastic windows tolerate temperature changes well and are frost-resistant

The statement is quite controversial. Frost resistance - this function is assigned exclusively to double-glazed windows. But very low or high temperatures (-40 – +40) are perceived differently by wooden and plastic structures. Wood is a natural material, hardened in the mentioned temperature conditions, so it is physically more durable. Because of his natural origin Wood, unlike all other materials, also has the lowest coefficient of expansion, which makes it ideal for use, for example, in very cold conditions. That is why wooden windows are especially popular in the northern countries - Finland and Sweden. PVC windows, especially considering the presence in their designs metal parts, in this regard, are quite vulnerable: a large temperature difference over time leads to a loss of insulating properties and, in general, structural strength.

8. PVC windows are less susceptible to deformation and are more durable

A very controversial statement. It is too early to draw conclusions about the durability of metal-plastic windows, since this product has been in use for at most 20-30 years. In fact, each of us has often seen old houses in which the wooden frames have not been changed for a hundred years or more. Even if their paint is peeling, the doors may not fit well, but with proper repairs they can last for many more years. And these are windows made at a time when they did not even think about the advanced technologies and materials used now. The only enemy of wooden windows is moisture, which leads to their deformation and infection with fungus and mold. But with proper care, this danger can be avoided. Plastic windows are also susceptible to other misfortunes. The main one is high coefficient expansion due to temperature changes, which gradually leads to loosening and loss of strength. And not only in the plastic itself, but also in the places where it meets the window opening.

The fact is that wooden frames are made from homogeneous materials (identical in physical properties), which have a similar expansion coefficient and equally perceive external influences. PVC windows in their design have different materials(especially metal fittings inside), and therefore tolerate significant temperature changes worse than wooden ones.
Without plastic ones metal base does not exist: polyvinyl chloride itself is a very fragile material, so without proper reinforcement the profile can be deformed. Another significant problem with metal-plastic windows is rubber seals. Even high-quality ones lose their properties over time, harden, and begin to crumble, especially under the influence of low and high temperatures, detergents, exhaust gases from the street, etc. They are inexpensive, but replacing the entire profile is a troublesome task.

9. Plastic is dangerous for the environment

The polyvinyl chloride from which window profiles are made is extremely dangerous for humans. No less dangerous are various additives (plasticizers, dyes), which are released into the air in small quantities (especially when heated). It is this fact that is often cited as the main argument in favor of wooden windows. But not everything is so scary. Firstly, most toxic and poisonous substances enter the atmosphere not from the finished window, but during the production of PVC raw materials.

Secondly, if you take into account the amount of plastic in the window and the volume of the room in which it is located, then the “harmfulness” from the released substances is reduced to virtually zero.

Thirdly, although the structure of the material contains harmful substances, this does not mean that they must necessarily enter our body (unless, of course, we burn or inhale combustion products). In addition, we are already surrounded by a huge number of products containing plastic: linoleum, toys, vinyl wallpapers, various packaging, etc.

Yes, there is virtually not a single thing around that does not contain some kind of poison. Another argument popular among opponents of plastic windows is that, unlike wooden ones, when polyvinyl chloride ignites, very toxic and poisonous substances are released. In this case, there is only one piece of advice: do not burn plastic windows in your apartment! Just a joke, but... But if, God forbid, it comes to a situation where the windows in the room are already on fire, then these fumes are unlikely to be significant in the overall picture of the tragedy. As is the environmentally friendly burning of wooden windows.

A person values ​​his health more than anything in the world, so concepts such as the harm or safety of a product have become one of the main tools in the struggle for consumers between competitors. Not surprisingly, this is the area most susceptible to subjectivity and bias. Sometimes a product that is hazardous to health is advertised as almost healing, and vice versa: a neutral product is presented as an environmental disaster.

10. Wooden windows look attractive

Wood products have always been valued for their beautiful texture, aesthetic and attractive appearance. But there is no arguing about tastes. For example, “concrete-glass-aluminum” is more suitable for a modern building metal-plastic structures than wooden ones. In addition, PVC windows are now very diverse both in shape and color (about 50). Wooden ones are somewhat limited in the arbitrariness of their designs (the radius of the arch is limited).

Hello, dear friends!
My name is Dmitry Provorov, I work as the head of the client department at the Just Windows company. As you may have guessed, I will talk about windows in my blog. And I know about windows.

There are a lot of offers on the window market: there are so many! And there are not many areas where the spread of prices for the same order would be as great as in windows. And this is if we talk about honest companies. I will definitely talk in detail about dishonest people and how to recognize them in the future. I’m going to boil down the essence of my blogs to one thing: how to understand which windows you need, how to recognize truly useful offers from advertising “tricks,” and choose the best option in terms of price and quality ratio. With all this, we will destroy marketing myths) I hope it will turn out interesting and informative.
So let's get started. Let's start with what to choose: plastic windows or wooden windows? Many articles have been written about this topic. But the whole point is what their marketers write, either to the company that produces plastic windows, or to their rivals, the “wood workers.” Well, and, of course, marketers are very far from construction physics and practical experience. Well, I have more than enough knowledge in these areas. At the same time, I will try to maintain neutrality and objectivity in my assessments.
Plastic windows, I think everyone can imagine it quite clearly, since at present this is the most common option. These windows are made of polyvinyl chloride (PVC). Naturally, the composition also contains various stabilizers, pigments, etc. Many people think that this is not environmentally friendly. But I’m sure you won’t find a single chemist who thinks the same way. Because all these materials strictly comply with all sanitary and epidemiological standards, GOSTs, SNPs and others. However, I still don’t recommend eating or smoking plastic windows, but I think you weren’t going to do that anyway)

A small nuance. The windows are positioned as German, English, Austrian and God knows what. It doesn't matter. Absolutely all PVC profiles are produced in Russia. There is, of course, the same Rehau Brilliant or Geneo, which many position as brought from Germany itself. I know only one company that brings Rehau Diamond from Germany, but their price will be about 25 thousand per square meter window. And I know many companies that deliberately mislead the client, simply deceiving. They can even make fake certificates.

There is nothing wrong, of course, that the profiles are made in Russia. But everyone positions their profile differently. And this often occurs with a loss in quality in order to reduce the cost. Therefore, the company that will implement your order must be chosen very carefully. I think my next post will be about this.

Everything is much more complicated with those windows that are made of wood.

They can be divided into several types: old Soviet (carpentry); new cheap ones (these are sometimes installed in new buildings); wooden euro windows; Swedish; Finnish.
Everyone has probably seen old Soviet windows and many still have them. They sometimes last for decades. They knew how to build back then! But everything comes to an end and they also need to be changed.
In new buildings, sometimes, quite rarely, wooden windows are installed with double-glazed windows and fittings of a modern type. The quality of the wood and processing is simply disgusting. I myself once lived in a new student dormitory with just such windows. A cold winter, then a hot summer - and the windows were incredibly warped. The gaps are so large that birds almost flew in. This option is even worse than the cheapest plastic windows from the developer.

Wooden Euro-windows. This is exactly what they mean when they ask: which windows are better - plastic or wooden.

According to the principle of operation and the sash with frame, such windows are similar to plastic ones. The double-glazed windows installed there are the same. They differ only in the profile material.

Such windows are made from three-layer laminated timber of various, usually valuable, types of wood. (Pine, larch, oak). You will not find exact technical characteristics, for example, sound insulation or heat transfer resistance. Each case is individual. But, approximately, according to these two indicators, these windows correspond to the middle class of plastic windows.

Everywhere they write that such windows “breathe” and are environmentally friendly. This is pure marketing. Nothing breathes there - it’s not just untreated solid wood, it’s three-layer laminated veneer lumber. Which is carefully treated with aseptics, fire protection, painted and so on. The environmental friendliness here is questionable, it’s like inserting a wooden beam inside a PVC profile.

These windows cost 3-4 times more than plastic ones.

It would seem then: why are they needed at all? But, for example, in Germany, where plastic windows were everywhere already in the 70s, they are being replaced by wooden Euro-windows. Here, of course, it is worth making an allowance that in Germany everything is in order with quality, but here they can deceive. It is not so easy to distinguish an ordinary Moscow pine from a Siberian larch. Although, perhaps, in 20 years, plastic windows will be perceived in our country as Soviet carpentry is now.

Well, for now, wooden windows are a matter of image. It's expensive, it's cool. It's like an insert in a dashboard in a Maybach made of Karelian birch. Otherwise, they are definitely no better than many plastic ones. At the same time, they require more careful care.
Well, now let's move on to the exotic) Swedish windows . Sweden is a country where clearly no fools live in natural conditions with a climate similar to ours. That’s why their windows are really cool) If we talk about regular Euro windows, then their design principle is approximately the same as that of PVC. Everything is clear here.

Swedish windows have a different design. There are two paired doors. The internal (the one in the room) sash is equipped with a single-chamber double-glazed window. And this flap is paired with another flap, which is 10 centimeters smaller than the inner one. And there is no longer a double-glazed window, but sheet glass. The outer sash itself is attached to the inner one and can be opened to, for example, wash the windows. Doesn't this design, by the way, resemble our joinery?)

It turns out that there is, as it were, a double frame: one for the inner sash and one for the outer one. There are more connection points between the frame and the sash compared to the classic design. This is, of course, good) Plus, there is a wide space between the outer and inner doors. It's really not airtight. And due to convection, it’s difficult to say for sure whether it’s good or bad that there will be a wide distance. But you can install blinds there)

There is also Finnish windows) They are almost the same as the Swedish ones, only the doors are not paired. That is, two separate doors. The rest is all the same.

In my opinion, the most significant difference between Swedish/Finnish windows and Euro/PVC windows is wide box. Due to this, the slopes freeze less. Another big plus is more sealing points for the frame and sash. If money allows, this is a very good option.

Well, and again about the price. Swedish/Finnish windows will cost 2 times more than wooden euro-windows. At the same time, in Russia there are still few people doing this. Therefore, you need to look in very large cities.

In general, a start has been made. I will add new posts regularly. And this is just a test of the pen. Happy repair everyone. And remember, windows are actually not that difficult. I would even say, Simple)

Let's try to compare the two types completely different windows and come to a certain conclusion. For convenience of analysis, we chose qualitative characteristics by which we compared the windows with each other.

After analyzing each characteristic, we evaluated the type of window being compared with the ideal, in our understanding, window. We made an assessment on a 10-point scale.

By what criteria did we compare?

• The need for ventilation
• Thermal insulation performance
• Diversity
• Aesthetics

The need for ventilation

Whatever material the windows are made of, in any case they must be ventilated. Possibility of window ventilation important characteristic on which it makes sense to compare windows. Let's try to determine which is better in this regard, plastic windows or wooden ones.

Ventilation of plastic windows

PVC, from which plastic windows are made, does not allow air to pass through, so ventilation of the room must be done using micro-ventilation or special supply mechanisms. Otherwise, in hot weather, a greenhouse effect will form or the air in the room will stagnate. An important feature of plastic windows is the ability to install a ventilation valve, which provides the necessary air flow for a person even when the window is closed.

Ventilation of wooden windows

There is an assumption that wooden windows “breathe”. Yes, wood is a natural material, and it breathes, but modern wooden windows (Euro-windows) have an important feature - they are impregnated with various kinds of substances that will not allow bugs to get into the wood, lose color, and prevent the wood from rotting under the influence of external factors. These substances prevent air from penetrating through the wood. Modern wooden windows allow only 3 liters of oxygen per hour to pass through. For normal existence, one person needs 85 liters of oxygen per hour.

To ventilate wooden windows, you can use micro-ventilation and tilt the sash. It is not possible to install passive ventilation valves on wooden windows.

Result

Both plastic and wooden windows need to be ventilated equally. Wooden windows breathe, but this is not enough. We will give an estimate in 8 points And 6 points. Plastic windows receive 8 points for the ability to install valves.

Operating cost and service life

An important indicator of the quality of windows is their service life. The service life of plastic and wooden windows directly reflects the savings from the purchase. For the calculation, we used the following conditions: the windows are installed correctly, the fittings and glass units are of ideal quality, the windows are lubricated and adjusted approximately once every 5–10 years. Only under this condition will they serve their allotted time.

Operation of plastic windows

Average term The service life of plastic windows is approximately 45–50 years. By comparing the costs of plastic and wooden windows, you can derive certain coefficients of the difference between these costs. Let's calculate the cost of operating plastic windows for one day, for which we take the cost coefficient of a plastic window equal to 1, and the conditional cost - 10,000 rubles per window. Let's find out the number of days: 47.5 years * 365 days = 17,350 days of operation. The operating cost per day will be 10,000/17,355=0.58 rubles per day (58 kopecks).

Operation of wooden windows

The situation is different with wooden windows, since the lifespan of wooden windows depends on the type of wood. Windows made of pine will last 55–60 years, those made of larch 50 years, those made of oak about 90. The cost of windows is also different, for example, the markup coefficient for windows made of pine is 1.4, for larch 1.7, for oak 2.1. The corresponding cost of daily operation will be: for a pine window - 14000/(57.5*365)=0.67 rubles; for a larch window – 17000*(50*365)=0.94 rubles; oak windows - 21000/(90*365)=0.64 rubles. We get the average cost of operating wooden windows: 0.75 rubles.

Comparison result

A comparison of plastic and wooden windows in terms of cost and service life showed that the cost of use and service life of wooden windows are 30% higher. If you laminate plastic windows, wooden windows will become about 20% more expensive. We will take this possibility into account when calculating points.

Result

Comparing windows by cost, we will evaluate plastic ones - 9 points, and wooden - 7 points. When compared by service life, plastic ones receive a rating of - 7 points, and wooden 10 points.

Thermal insulation performance

No less important indicator The quality of windows is their ability to retain heat. Unfortunately, there is no correct data on the thermal insulation of windows, since thermal insulation, first of all, depends on the double-glazed window and the quality of the fittings, and we compare only the material from which the frames are made. But, we think, it is already clear to everyone that, under equal conditions, wooden windows are warmer than plastic ones. Plastic windows receive 8 points, wooden - 10 points.

Resilience and Reliability

Susceptibility to impact - the ability of windows to break. Fragility refers to limitations in use, as well as the likelihood of breakage under the influence of various factors. Let's not forget that a window consists of a frame, double-glazed windows, and fittings. In this section we only compare what can happen to a window frame.

Reliability of plastic windows

With time, window frame some manufacturers may turn yellow. The frame can shrink and expand under the influence of temperature. If the window is not properly reinforced, then under the pressure of the walls the window profile may bend in an arc. If scratches appear on the frame, they can be easily removed.

Reliability of wooden windows

Wooden windows can bring you more surprises. If the paint is light, then the sun may darken the wooden window. Also, if you accidentally scratch the frame, you will not be able to repair the scratch, so you must be extremely careful with wooden windows. Wooden windows can catch fire when exposed to fire.

Result

Plastic windows are less demanding to use and get paid for it 8 points, wooden ones - 4 points.

Diversity

As you know, windows can be of any shape, any color, in many configurations and variations. Let’s compare windows based on this indicator and determine which ones are better.

Plastic windows

Plastic windows can be laminated, you can easily make them arched, you can paint them in different colors from different sides . A window of any shape and color, in any variation, can be made from plastic. The only unpleasant moment is the difficulty of making sashes that are too small and too large.

Wooden windows

Wooden windows can also be arched, but there are significant restrictions on the shape of the arch. There are also restrictions on priming windows. Unfortunately, it will not be possible to prime one side with one color and the other with another. You can paint it any way you like, but you can’t prime it. Also, in wooden windows there are such concepts as false sash and additional timber on the sash, which, in some cases, cannot be avoided.

Size restrictions are approximately the same as for plastic windows. There is one in the wooden windows important feature- they can be combined with an aluminum trim and get a window of a completely different quality. It is impossible to install single-chamber glass in wooden windows.

Result

Plastic windows provide great opportunities for designers, and are also more versatile, for which we rate them 8 points, wooden windows receive 7 points, but only thanks to the ability to make them wood-aluminum.

Aesthetics

Windows should be beautiful. This is a very important window parameter. Let's compare windows according to their aesthetic indicators.

Plastic windows

Windows can be painted any color, as well as laminated to match any type of wood. But still, the plastic will be visible to the naked eye. The artificiality of the material does not always add beauty to the windows. Whatever the design, such windows will be artificial.

Wooden windows

In aesthetic terms, wooden windows have no equal. I think you will agree that the most beautiful are wooden windows. Undoubtedly and without a doubt.

Result

Plastic windows are common and everyone has long been accustomed to them. They no longer surprise anyone, which cannot be said about wooden ones. If you have a wooden dacha or cottage, then plastic windows, even laminated ones, will look completely different from wooden ones. We evaluate the aesthetic indicators of plastic windows in 6 points, and wooden ones in 10 points.

Final result

We compared plastic windows with wooden ones and received different ratings for each parameter. To make the results clearer, we have compiled a comparison table.

conclusions

The overall result of comparing plastic and wooden windows was absolutely the same. Of course, it is clear that for each person the compared window characteristics have different degrees of importance. For some, sound insulation is important, for others, the most important thing is for the windows to be warm. We made the comparison based on our own preferences. For us, the result was the same, so we can come to the conclusion that the need to install plastic or wooden windows varies depending on each specific case. We could not come to a clear conclusion which windows are better, plastic or wooden.

For residential buildings in the city, we would recommend plastic windows. For old buildings and buildings that are architectural monuments - plastic laminated or wooden windows. For dachas and country cottages, we recommend installing wooden windows.

Wooden windows are no longer what they used to be. Implementation innovative technologies production made it possible to eliminate most of their shortcomings. Now they can adequately compete with plastic in terms of durability, practicality and functionality. At the same time, “Euro-windows” are still beautiful and safe. Let's look at the features of wooden window blocks in comparison with PVC structures.

Why don't people like PVC in Europe?

Polyvinyl chloride. Not a very beautiful and a little scary word, isn’t it? This is the name of the now incredibly popular basic synthetic polymer. This material has a number of outstanding performance properties, which is why it quickly found application in almost all industries and especially in construction. PVC gets its specific characteristics thanks to a certain set of various additives. Plasticizers facilitate the processing of polyvinyl chloride, make it elastic, stabilizers prevent destruction during the production and operation of products, modifiers improve specific physical properties, fillers reduce cost, dyes allow the production of colored products.

For more than 80 years, polyvinyl chloride has been marching victoriously across the planet, but it is constantly being reproached regarding the safety of PVC products for humans. PVC manufacturers fight fiercely for their products; they are ready to prove their environmental friendliness with all their might. A countless number of tests have been carried out and many certificates have been obtained. But there are no completely safe additives for polyvinyl chloride.

Recently, one famous manufacturer plastic profiles announced that it would stop using extremely harmful lead and switch to calcium-zinc stabilizers.

And this after almost forty years of manufacturing plastic with lead? How many years from now will we be told the truth about calcium, cadmium, zinc? The Russian consumer, who is financially able to afford high-quality European windows, is at a crossroads; he is well acquainted with the terrible wooden products Soviet era, but something worries him about the PVC windows. Many are not ready to completely and completely trust official sources, much less the aggressive advertising statements of plastic window sellers.

Naturally, we are not trying to reinvent the wheel, but are turning to the experience of Western European countries, especially since manufacturers of plastic windows are happy to provide relevant statistical data in their booklets. When they say that in Germany the share of plastic structures makes up more than 50% of installed window systems, it is true, but this percentage concerns the total mass of translucent structures. In the homeland of PVC, 70% of residential windows are made of wood, and their share is constantly growing - by 3-4% per year, naturally due to plastic. If we talk about the Scandinavian countries, more than 70% of all windows there are wooden. The percentage of windows made of wood drops slightly in countries with small differences in annual temperatures and poor forest reserves, such as Spain, Italy, and France. The reality is that, despite the global financial crisis, Europeans prefer parquet, cotton and wooden joinery to linoleum, synthetics and plastic windows, and the PVC window market is quickly and confidently shifting towards Eastern Europe.

What properties do wooden windows have?

Wood is pure natural material, which initially has excellent technological qualities: low thermal conductivity, good sound insulation, resistance to temperature influences, high strength. Unfortunately, wooden windows are afraid of moisture. Wood needs reliable multi-stage protection, including from insects, microorganisms, and fungi. The production of translucent structures made of wood is a high-tech, time-consuming, and expensive business.

Naturalness and beauty. Wooden windows are the embodiment home warmth and comfort, the aesthetic characteristics of wood products remain beyond competition, despite fairly successful attempts to copy its texture. High-quality wooden windows can become the highlight, the core of the entire interior, and largely determine its style. Even staunch supporters of PVC windows, being adherents of the practicality and affordability of plastics, will not argue with the exceptional attractiveness of the natural material. Thanks to the ability to process wood manually or using digital equipment, wooden window manufacturers can offer consumers products of a wide variety of non-standard shapes. In turn, the desire of designers and developers to use some kind of “special” plastic window in the interior is simply impossible due to the official laconism of angular PVC profiles.

Strength. Any type of wood consists of fibers oriented in a certain direction, which, with a competent approach, alternating their direction in laminated timber, allows you to create very strong, durable, geometrically stable products. Compared to PVC windows, which are necessarily stabilized with a metal liner, they have a disproportionately lower coefficient of thermal expansion. On this moment Windows are most often made of pine, oak, larch, beech, cedar, fir, spruce, and mahogany. Each type of wood has its own indicators of strength and durability. But do not forget that the denser and stronger the material, the greater thermal conductivity it has.

Insulating properties. Wood has natural porosity and contains air in capillaries. Therefore, with equal thickness of the profiles, a wooden window retains heat and dampens sound vibrations somewhat better than one made of multi-chamber plastic. On average, oak is 20-25% warmer than PVC, pine - 25-30%.

The need for protection and periodic care. The stumbling block for wooden windows is atmospheric humidity. Wood can easily absorb moisture from the air, which causes the fibers to swell—the product fails. Rapid loss of moisture causes cracking and warping with subsequent loss of insulating properties. It is precisely because serious protective measures must be taken that the overall technological chain is so long, and the cost of wood products remains consistently high. Multi-stage processing only wooden profiles antiseptic impregnations, primers and paint and varnish compositions will provide windows with practicality and durability. However, no matter how technologically advanced the coating is, it has its own service life, so every 3-4 years, sometimes more often, it is necessary to tint wooden window blocks, in particular the lower horizontal parts of the folds, the most vulnerable from rain and ultraviolet radiation. That's why they appeared combination windows, as well as options with aluminum or plastic overlays over wood. In addition, with each year of operation protective covering loses approximately 0.01 mm of thickness, which is why a wooden window should be periodically treated with special polishes and varnishes.

Environmental friendliness. To be fair, we note that, despite the obvious safety of wooden windows, their production cannot be imagined without the use of a certain amount of “chemistry”. Porous fillers, primers, putties, paints, glazing compounds, antiseptic impregnations, glue for making timber, butyl sealants for double-glazed windows - this is what manufacturers of PVC windows talk about when discussing the environmental safety of wooden window systems.

"Breathing" of wooden windows. Manufacturers of wooden windows claim that their windows “breathe”. Some even say that through micropores wooden boxes There is an air exchange of such a volume that is capable of providing ventilation of the room, preventing condensation. They are a little disingenuous. The sashes of wooden windows have several sealing contours; the wood is treated with compounds that fill the pores - in other words, such structures are practically airtight. The air entering the room through the window will clearly not be enough for normal ventilation (GOST 24700-99 “Wooden window blocks with double-glazed windows”), condensation will appear. That is why serious companies persistently offer their clients wooden windows with installed ventilation valves, which were originally invented for PVC products.

High price. Despite all the advantages of wooden windows, their price is quite high compared to plastic ones. For example, a standard window block made of pine (1.45x1.8) already in the basic configuration will cost $600-800, any other type of wood will increase this price by an order of magnitude. This largely explains why domestic consumers prefer to order plastic windows several times cheaper, which, moreover, “don’t need to be painted,” “it’s not wood—they won’t crack or dry out,” “set it up, wipe it with a cloth and forget it.”

How wooden windows are made

The material and profile design are the main things that distinguish wooden windows from PVC products. The production of high-quality window profiles from wood is a complex, time-consuming and very labor-intensive task. It is not surprising that, as soon as the first samples of Euro-windows appeared in the post-Soviet space, energetic owners of traditional “carpentry” quickly noticed their promise and tried to establish corresponding production, but were never successful. Even now, many companies that assemble wooden windows work with a purchased profile.

In most cases, modern wooden windows are made from multi-layer laminated veneer lumber. It is not unreasonably believed that it has greater strength, better resistance to temperature changes, and less hygroscopicity compared to solid wood. Some manufacturers have mastered the technology of producing high-quality windows from solid northern pine, which is carefully selected and equally carefully dried. Raw materials intended for the production of timber undergo several rather complex stages of preparation.

First of all, the wood goes through several stages of drying, the full cycle of which takes some time:

• natural drying,
• processing in the chamber - steaming and dry heating with alternating temperature indicators,
• normalization of temperature and achievement of humidity balance.

Drying is designed to remove internal stresses inside the wood, and also eliminate the possibility of cracking during processing. The preparation of boards in drying chambers is carried out automatically, according to a given program for certain types of wood. Optimal humidity raw materials at the output ranges from 10-12%.

Next, the wood is discarded (optimized). Areas with knots, cracks, resin pockets, core remnants, wormholes, shells and stains are cut out of the board. This is how small planks are obtained - plots, on the ends of which jagged tenons are milled. They are coated with water-repellent glue and, under pressure, spliced ​​into one long board - a lamella. The glued lamellas are kept in a press for some time, after drying they are planed (calibrated).

The next stage of profile production is gluing the timber in thickness. The boards are glued together under pressure, flat, while the inner layers are made of spliced ​​lamellas, and the outer ones are mainly made of solid ones. As a rule, a three-layer beam is made, but some companies use technology with a larger number of layers, and some lamellas can be glued to the sides of a three- or four-layer cake.

It is very important that the fibers of adjacent lamellas are directed in opposite directions. Only such laminated veneer lumber is considered to be of high quality and is capable of ensuring the stability of the geometric shapes of the product.

Then the wooden beam is milled using computer numerical control equipment, resulting in a window profile with a very complex cross-section. For the production of windows with exclusive, non-standard forms An individual approach, “handmade” may be required.

Further, the process of making a wooden window is significantly accelerated. The frame is assembled, sanded, treated with impregnation (under pressure or vacuum), primed, and painted. After finishing the painting work, double-glazed windows and seals are installed, fittings are mounted, and sashes are hung.

Wooden window design

Modern wooden windows are structurally similar in many ways to plastic products. For their operation, the same fittings are used, which allows for not only rotary, but also tilting, tilt-and-turn opening of single sashes. They also have multiple sealing contours. For glazing wooden windows, not only sheet glass is used, but also various types of double-glazed windows, including special, energy-saving ones. The main difference between wooden windows is that they can have several design schemes depending on the number and type of sashes. Note that some constructions are historically associated with a specific country, which was the reason for their “folk” classification based on nationality.

Single-leaf windows. This is the so-called European type, Eurowindow, German window. In fact, this is a direct analogue of plastic windows, with the only difference being that the profile is made of laminated veneer lumber. With a profile width of 68 millimeters or more, any type of glass unit from 36 to 44 mm is installed in them. The design of the rebate allows the use of two or three sealing contours for Euro-windows; modern fittings make it possible to control all operations with the sash using only a handle. The fittings for such wooden windows are produced by the same companies that work in the market of PVC products: Roto, Maco, Siegenia-Aubi... Naturally, options such as winter slot ventilation, stepped opening, burglary protection and others become available to the consumer. Single-leaf wooden windows are currently the most common in our country.

Windows with separate sashes are also called “Finnish”. This window block has a large frame width, about 120-180 mm. To the outside and inside boxes are hung with sashes independent from each other, as on Soviet windows. Sheet glass is inserted into the outer sash, which serves as a kind of buffer from the effects of various factors. environment, and the inner sash is equipped with a single-chamber, often energy-saving double-glazed window. Interestingly, the outer glass seal is not airtight, which prevents condensation from falling on it - it is just a so-called “boot”. The fittings that work in windows with separate sashes allow only rotary opening, so ventilation is carried out using a window or a sash opening limiter. Thanks to their two-chamber design, such windows have excellent insulation characteristics; the significant width of the frame prevents freezing of the slope. Inside the Finnish window, between the sashes spaced at a great distance, sun blinds are installed, sometimes even removable grilles.

Windows with paired sashes are supplied to us mainly from Sweden. They also have a two-frame design. Their main difference from windows with separate sashes is that the internal sashes of such window blocks are connected to the external ones by means of sliding connecting elements. The inner sash has locking tilt-and-turn fittings, controlled by a single handle. Therefore, many people also call designs with paired sashes “Euro-windows”.

It is difficult to say for sure which wooden window design is better; each of them has its own pros and cons. For example, double-glazed window single-hung windows and double-hung window glazing (flat glass plus double-glazed windows) have approximately the same insulation characteristics. The wooden frame of double-hung windows is warmer due to its large width, but at the same time you have to take care of not two, but four planes; The separate design does not have the much-loved hinged opening function. Of course, “Scandinavian” windows are more expensive than “European” ones, but if you compare blocks with similar sound and heat insulation, the difference will not be very significant, especially when the first ones are made in Russia and the second ones are made abroad.

What should you pay attention to when ordering wooden windows?

Foreign manufacturers of wooden windows have firmly established themselves in the Russian market. They are constantly working to improve the quality of wooden translucent structures and reduce their cost. Every year we are offered fresh design developments, new protective compounds and types of profiles. Western companies carry out a full cycle of work from timber harvesting to the manufacture of double-glazed windows; they have large high-tech factories. Our manufacturers work using European technologies, using imported equipment; many of them purchase profiles and double-glazed windows externally, often abroad.

Imported windows are approximately one and a half to two times more expensive than Russian ones.

From measurement to delivery you will have to wait until three months, while domestic companies usually fulfill orders within 3-8 weeks.

In most cases, a comprehensive guarantee is provided - for the profile, double-glazed windows, protective coating, and fittings. Naturally, the window must be installed by the manufacturer's specialists. Russian companies usually give a 3-year warranty on their products, foreign ones - 5 years.

Windows made of oak are approximately 2 times more expensive than those made of pine; larch - 1.5 times.

Wooden window blocks made from timber with spliced ​​external lamellas will be cheaper on average by 15% than with solid ones.

You can save money by ordering a profile in which the outer layers are made of expensive wood, such as oak, and the inner layers are made of pine. There are options with profile finishing with valuable wood veneer.

Windows of standard sizes are also somewhat cheaper than those made to order.

How longer term manufacturing, the lower the cost of the window - this is how manufacturers regulate the flow of orders. But for urgency you will need to pay up to 20%.

Blocks with paired and separate doors are 15-25% more expensive than single doors.

Often, you can order related products from the window manufacturer that match the frames in color and texture: window sills, slopes, trims.

It is quite obvious that modern wooden windows will find their place in our country; from year to year they will become more practical and affordable. The plastic boom will end sooner or later, and the share of wood windows will begin to grow, especially since the Russian climate is quite harsh, while we have decent forest reserves, and we have centuries-old traditions of wooden construction behind us.

With the collapse of the Soviet Union, the use of modern building materials in Russia came into balance with Western countries. Any new items come to to the Russian consumer almost instantly and at the same fast pace gaining popularity. However, this trend is not followed in the selection of windows. In Europe, 60% of windows in residential premises are made of natural wood, in Russia - more than 90% are made of plastic, or more precisely, metal-plastic. Why is this happening? What is really better - wooden or plastic windows?

At the time of the market takeover in post-Soviet countries, plastic windows cost 4-5 times more than wooden ones. Despite this, the population massively replaced their wooden windows with them. For the consciousness of the Western consumer, it is nonsense to overpay for “chemicals” several times, replacing natural wood with PVC.

But people of the older generation know very well what the reason is: the low quality of the windows they had, or rather, any lack of quality. The system for monitoring compliance with GOSTs and technical specifications was only on paper at that time. As a result, wooden windows, popularly called “carpentry,” either dried out or swelled from moisture, making them difficult, and often impossible, to open.

Adding to the problems was the short service life - they rotted quickly, and constant repainting - the paint on the outside lasted 2-3 years. The younger generation remembers the situation with wooden windows from their childhood impressions and also, according to the tradition laid down by their fathers and grandfathers, prefer metal-plastic windows.

Modern technologies have radically changed the process of producing natural wood windows. They have completely different consumer qualities. Many owners of apartments and private houses simply do not know about this. Let's try to figure out which windows are better - plastic or wooden.

Advantages and disadvantages of plastic windows

The first consumers began installing plastic windows for:

• Their practical design. They are quickly produced to fit any window opening, easy to open, and in several planes;
• Long service life;

• Good sound insulation, which increases with the number of chambers between the glass;
• Absence of drafts - rubber seals eliminated the boring operation of covering windows with paper tape with the onset of winter;

• Easy maintenance that does not require repainting the frames during the entire service life of the windows. In addition, they are easy to clean - water and detergents will remove any type of dirt.

In addition to the listed advantages, you should add modern design and high-quality fittings. However, like any product made from artificial materials, this type of window also has disadvantages:

• At temperatures above 27 o degrees Celsius, harmful substances begin to be released from the plastic, as evidenced by a barely noticeable odor;
• The windows do not breathe at all, as a result of which the room during hot weather, if all the doors are tightly closed, becomes very stuffy and hot, which greatly affects indoor plants in the absence of owners for 2-3 days;
• Cannot be repaired or restored. Any mechanical damage (scratches, impact marks, distortions, split seams) cannot be repaired.

Advantages and disadvantages of wooden windows

Windows made of natural wood also have advantages and disadvantages (hereinafter, Euro-windows are compared). The advantages include:

• Environmentally friendly - all window materials are natural;

• Harmonious combination with any wall materials (brick, concrete, stone, wood);
• Long service life - from 50 to 100 years, depending on the type of wood from which the window frame and frame are made;
• High strength - a wooden window is difficult to damage. It can withstand almost any impact load, and scratches, if they are left, are repaired with special compounds;

• Stylish design - a wide range of colors allows you to choose the color of the window to match the color of the walls;
• Good heat and sound insulation. Their level increases with the number of sheets of glass installed in the frame;
• Natural air circulation, allowing you to maintain a comfortable microclimate in the room;
• Durable fittings;
• Ability to open in several planes;
• High level fire safety— the material is treated with fire retardants;
• Ability to repair or replace damaged areas.

Unlike plastic window designs, wooden ones have only one drawback - they need to be repainted every 5 years.

From the above pros and cons, it is difficult to determine which is better - plastic or wood windows, and therefore we will continue the comparison by assigning the number of points for each compared position (the maximum possible score is 100 points).

Performance Comparison

We will compare according to the following criteria:

• cost of acquisition, installation and operation;
• life time;
• thermal insulation;
• soundproofing;
• design;
• practicality;
• breathability;
• environmental cleanliness.

Cost factor

What is cheaper, plastic windows or wooden ones? Replacing windows is an expensive type of repair:

• the price of a plastic double-leaf window starts from 3600 rub./m2, with installation - from 7300 rub./m2;
• wooden (grade III pine) from 3800 rub./m2, with installation - from 7500 rub./m2.

Grade 1 pine costs one and a half times more, oak windows cost 2.5-3 times more. But this is if we take into account one-time costs. If we decompose the cost of materials and installation for each year and month of service life, which economists call depreciation, then the picture is almost equal:

• depreciation charges for PVC windows will be 20.27 rubles. per month (7300/30x12);
• pine (grade III) - 13.39 rubles. (7500/45x12);
• oak - 20.27 rubles. (7500x3/90x12).

Attention: fittings and sealing gaskets for wooden and plastic windows are from the same manufacturers. Therefore, this factor is not taken into account.

Due to the 3 times longer service life, the monthly costs for oak and PVC windows are identical. However, when comparing the factor in points, preference must still be given to plastic windows - there are few people willing to invest in the distant future.

Another factor in favor of metal-plastic is that wooden windows need to be repainted approximately every 5 years, and this again costs money.

Conclusions.

• Expensive oak windows are economically justified when building expensive cottages - the service life of the window practically coincides with the service life of a new building.
• IN apartment buildings It is impractical to install windows with a service life of more than 50 years - it is unknown how long it will take for high-rise buildings to be demolished due to complete wear and tear of the load-bearing structures.
• Money for installing windows is paid here and now. Considering that most people do not look into the distant future (in our subjective opinion), advantage in points 90 to 65 in favor of PVC windows.

Lifetime

Manufacturers of plastic windows until 2010-2012 guaranteed a service life of their products of 20-30 years, recently 40-45. It is not yet possible to verify their approval in practice - windows with changes in production technology lasted no more than 8 years. However, there are significant doubts about the stated figures.

• Under influence ultraviolet rays sun, rain and temperature changes, the plastic turns yellow. It is doubtful that the owners of wealthy apartments and private houses will tolerate windows that spoil the design. Most likely they will replace them.
• A different coefficient of expansion when the temperature of the plastic and metal profiles fluctuates leads to a gradual loosening of the frame itself and a violation of the strength of the fastening of the window block with the window opening.

Wooden windows do not have such problems. In villages and towns, in ancient houses you can see wooden frames with a service life of 100 years or more. The tree is afraid of dampness, but with proper care it lasts a very long time. At modern methods wood processing, it is not afraid of dampness and mold.

Therefore, as in the case of plastic windows, the manufacturers’ statement about the service life of pine windows of 45-55 years is questionable. Real time their service life is 70-80 years. Conclusion: the assessment of the service life of PVC windows is 60 points, wooden ones - 100.

Which is warmer

For the consumer, knowing which windows are warmer is very important. Therefore, the thermal conductivity coefficient is one of the main indicators by which consumers choose the type of window. The ability to retain heat in a house or apartment near a window depends on the glass unit and frame. Since the number of cameras of both types of windows can be equal, consider thermal insulation properties ram.

For plastic, the heat transfer coefficient is 0.15-0.2 W/m 2 xK (the range of spread depends on the number of chambers and the width of the PVC profile). Solid wood frames also have different heat transfer rates. The lowest for larch is 0.13 W/m2 xK, oak and pine are 0.15 W/m2 xK. However, for a frame made of laminated veneer lumber it is much less - 0.1 W/m2 xK.

Conclusion: plastic windows deserve 85 points, wooden ones - 100.

Which windows have the best sound insulation?

Wood has porosity - the capillaries contain air, plastic does not. With the same profile thickness, wood on average dampens sound waves better by 15-20%. Conclusion: PVC windows - 80, wooden - 100 points.

Design

The aesthetic perception of windows is no less important than their functionality. When choosing windows, you always pay attention to how they fit into the interior and how they look against the background of the facade.

Plastic windows have much more design possibilities (they can be laminated, painted in different colors, given different shapes) than wooden ones. But there is one thing. Any laminate flooring natural materials It immediately catches your eye - artificial material will always remain artificial. Wood has no equal materials in terms of beauty.

Conclusion: judging by a combination of factors (design capabilities and aesthetic perception). a plastic window has 85 points, a wooden one - 100.

Practicality

When choosing what is more practical, consumers have different requirements for windows. For some, it is important how easy it is to wash them, for others, maintenance of windows during operation comes to the fore, for others, the ability to repair the frame and window unit if damaged, etc.

It is easier to care for plastic - it can be easily washed with any detergents. Wood is a little inferior in this regard. During operation, the most difficult problem with wooden windows is the need to paint them regularly, approximately every 5 years. Especially outside.

Manufacturers have taken this disadvantage into account and offer owners of wooden windows aluminum overlays that protect the paint from exposure to UV rays. Firstly, they need to be painted less often, and secondly, they can be removed and painted in an apartment or garage, which is much more convenient.

Plastic windows cannot even undergo minor repairs, unlike wooden ones, where frame and window elements can be replaced. Conclusion: PVC windows - 80, wooden - 65.

Breathability

Oddly enough, the “joinery” of the Soviet period had one undoubted advantage - there was always fresh air in the apartment, even with the window closed. The advent of plastic windows saved homeowners from constant drafts, but created new problem— blocked the air exchange, since the polyvinyl chloride material does not allow air to pass through at all. The tree breathes - fibrous structure the material is breathable.

Manufacturers took into account the shortcomings of plastic and began to produce PVC windows with ventilation valve, which radically changed the assessment - wood allows air to pass through, but not to such an extent that it can provide complete air exchange without special ventilation.

Conclusion: plastic windows with a ventilation valve do not require ventilation, so the score is 80 points. Wooden windows have 60 points.

Which is healthier?

Both types of windows fully comply sanitary standards and rules. However. as the temperature rises. plastic begins to smell and release lead atoms into the air (fouling), which wood does not. In the West, manufacturers have abandoned lead additives, but in Russia they have not yet.

Therefore, when purchasing PVC for windows in Germany, the risk of harm to health tends to zero. Artificial materials from Russia have risks of negative impact on the health of family members. Note that this factor is the main one when choosing the type of windows in Western countries.

Conclusion: despite the highlighting of plastic windows when high temperatures a certain amount of harmful substances, they do not exceed the limits established by sanitary services. Therefore, plastic is 85 points, wood is 100.

For clarity, let us summarize the results obtained in a table:

Comparable parameters	Their windows are PVC, points	Wooden windows, points
Price 1 m 2 windows	90	65
Lifetime	60	100
Thermal insulation	85	100
Soundproofing	80	100
Design	85	100
Practicality	80	65
Breathability	80	60
Environmental friendliness	85	100
Result:	645	690

The table shows that in a comprehensive analysis, wooden windows have an undoubted advantage. However, window buyers are primarily interested in cost, practicality and the ability to retain heat. Here PVC already has an advantage (255 by 230), which mainly explains the very high popularity of plastic windows.

Where and what windows are best to install?

We looked at the pros and cons of installing plastic and wooden windows for an apartment. For a bathhouse, a summer house and an attic type of living space, the criteria are slightly different.

Country house. Install expensive wooden windows in country house not rational. Some of the disadvantages of polyvinyl chloride are unnoticeable with periodic visits to a summer cottage and the simple design of the building. Therefore, PVC windows are an ideal option.

Bathhouse. Those who like to take a steam bath, despite the price, will prefer a window made of alder or pine. Such windows hold steam perfectly and smell like natural wood, not plastic.

Studio apartment. Mansard type housing requires glazing large area. This automatically excludes the choice of wooden windows due to the high cost of work.

Loggia. To install windows in the loggia you need frame type window. Wood is very expensive to use. That's why they're made of plastic.

Conclusion

Each type of window has its own advantages and disadvantages. Comparative analysis showed that:

• plastic is cheaper;
• wood lasts longer;
• Thermal and sound insulation is better for wooden windows;
• the design of PVC is more varied, but aesthetically wood looks much better;
• practicality and breathability are higher for plastic windows;
• healthier wooden windows.

In bathhouses it is better to install windows made of alder or pine; in a country house, in a studio apartment and in a loggia, the best option is a window made of polyvinyl chloride.