10 tips for choosing the best glass for modern windows

The glass part of the window occupies about 90% of its area, so for the most part the heat and noise insulation of the entire structure depends on it. If you want a really warm and quiet window, then it’s not enough to buy a profile from a famous manufacturer - it’s important to choose a suitable double-glazed window, and here some difficulties associated with a huge assortment await us. Manufacturers offer double-glazed windows, differing in the number of cameras, type of glass and many other parameters, and since technology does not stand still, new and increasingly advanced solutions appear every year. To choose the best double-glazed window, you must carefully study all the offers on the market and determine your own requirements. Let's put everything on the shelves.

No. 1. Than a double-glazed window is better than ordinary glass, or a double-glazed window design

Even the simplest modern double-glazed window will be several times warmer old window with ordinary glasses. This was achieved thanks to the implementation of a number of design features. A double-glazed window today is called a complex structure consisting of several glasses connected to each other by a distance frame. The space between the glasses is called the camera, in most cases it is filled with air, but can be filled with inert gases to increase thermal insulation. Two glasses form one camera, three - two cameras, etc.

A moisture-absorbing substance may be inside the spacer that absorbs excess moisture and prevents fogging. Double-glazed windows are inserted into a profile from PVC, wood or aluminum: the palm that holds the plastic profile for a year in a row.

If a multi-chamber double-glazed window is used, then distance between glasses within one design may vary, but at the same time it will not be more than 20 mm. Reducing the distance allows to negate thermal convection between the glasses, and as a result, it is possible to save a significant part of the heat of the inner glass and not let it out. This is the basis of more efficient thermal insulation of double-glazed windows in comparison with old windows. To create the most warm and quiet window, manufacturers introduce many other technologies, such as using special glasses, gaskets, filling the chamber with argon and xenon.

No. 2. Number of double-glazed cameras - a key feature

In warm Europe, single-chamber double-glazed windows are considered the most popular, and two-chamber double-glazed windows are rarely installed there. In the harsh domestic climate, you can not even look at single-chamber structures - in most regions two-chamber double-glazed windows will be optimal, and in some especially cold regions - three-chamber.

The more cameras in the structure, the warmer the window will be.and physics explains it very simply: in several chambers it is possible to enclose a larger heat-protective layer of air, and it prevents convective heat transfer. So, for example, the average single-chamber double-glazed window has a heat transfer resistance of about 0.3 m²K / W, two-chamber - 0.5 m²K / W, and three-chamber - 0.7 m²K / W and more. But a large number of cameras have their drawbacks, so it is not appropriate to insert a three-chamber double-glazed window in every window.

Consider the advantages, disadvantages and areas of use of double-glazed windows with a different number of cameras:

• single chamber double-glazed window - the cheapest option, it has a minimal weight, and the lighter the design, the more reliable it is in the window opening and the easier it is to install. The advantages of double-glazed windows with one camera include a high level of translucency, but in practice, single- and double-chamber double-glazed windows differ little in this indicator. The main disadvantage of the design is insufficient thermal insulation, therefore, use such double-glazed windows in regions where in winter the temperature drops below -5⁰C, unreasonable. They release heat from the apartment, and due to structural abilities they have the ability to fog. Sound insulation level is weak.therefore, even in warm regions, such double-glazed windows are not recommended to be installed in bedrooms. The design should be used for windowsleading to glazed loggia, in unheated, office and technical premises, as well as in the southern latitudes. Manufacturers also offer single chamber double-glazed windows with low-emission glass and argon-filled chamber - this option almost catches up with double-glazed windows in terms of thermal insulation, it is cheaper, but still not suitable for windows overlooking noisy busy places;
• double-glazed window - The "gold standard" in our climate. Consists of three glasses and two air chambers. In terms of heat and noise insulation, a two-chamber double-glazed window is more than 30% superior to a single-chamber. It costs, of course, more expensive, but also on heating you will spend less. Given harsh winters, the price difference between single and double-glazed windows pays for itself in 1-2 years. The most popular is a double-glazed window with a glass thickness of 4 mm and cameras between them of 14 and 12 mm (only 38 mm). Such structures are installed in residential and commercial buildings, as well as outside the city;
• three-chamber double-glazed window - salvation for the northern regions of the country, where in winter the temperature lasts for a long time around -40⁰C. If winter temperatures are significantly higher, the difference between the two- and three-chamber double-glazed windows will be insignificant and not very noticeable. The width of a three-chamber double-glazed window reaches 58-60 mm, and the presence of four glasses greatly increases the weight of the structure. To maintain such a burden, you need either a very wide profile, or division into numerous sections to reduce the load on the fittings and fasteners. All this increases the cost of construction, in addition, a three-chamber double-glazed window transmits somewhat less sunlight. With all this, it makes sense to put up only in extremely harsh climates.

Double-glazed windows with four or more cameras are considered exclusive, and their necessity is a big question.

No. 3. Type of glass in a double-glazed window

A classic option is the use in a double-glazed window ordinary float glass 4-6 mm thick. The technology allows you to get perfectly even and uniform in thickness glass, which perfectly transmits light from the street. The standard is glass with a thickness of 4 mm, thicker (5-6 mm) is recommended for use in noisy areas and on the upper floors, where gusts of wind have a decent power. An ordinary double-glazed window has good heat and sound insulation properties, it resists fire well, but there is no limit to perfection - today there are glasses where certain characteristics are significantly improved.

In addition to the usual, can be used and special double-glazed windows:

• energy-saving low-emission double-glazed windows allow you to keep warm in the apartment and reduce heating costs. Regular glass acquires unique properties thanks to spraying substances that transmit long-wave radiation, but delay the short-wave, in other words, light enters, and heat does not come out. Today most commonly used silver ion i-glass: They show excellent thermal insulation properties, but are afraid of weathering. K-glass cheaper, more resistant to negative environmental factors, but from the point of view of energy conservation less efficient. Energy-saving, as a rule, is only one glass in a double-glazed window. In summer, it perfectly reflects the heat from the street, and in winter it does not allow home heat to leave the apartment (see illustration). Filling the cells with argon allows you to further increase thermal insulation. It is estimated that when using low-emission glass, it is possible to increase the heat transfer resistance of a single-chamber double-glazed window to 0.56 m²K / W, and of a two-chamber to 0.75 m²K / W (the level of a conventional three-chamber);

• sun glasses indispensable in those cases when the window faces south, and the sun's rays literally blind the household and spoil wallpaperfurniture items carpets etc. UV protection glass tinted in bulk, glass coated with tinted film, tempered glass and glass with a mirror surface. A solar pane can become energy-saving at the same time if the inner glass is coated with silver ions, which reflects the thermal radiation from radiators back to the apartment;
• soundproof double-glazed windows distinguished by the use of multilayertriplex glass and soundproof film. To improve sound insulation, a special acoustic polyurethane foam. The complex of such solutions allows reducing street noise by 35 dB or more. Moreover, triplex glass is an increased safety and thermal insulation. Soundproofing depends on many other factors, which we will discuss further;
• fireproof double-glazed windows can withstand high temperatures and be absolutely safe for humans through the use of a metal grid on which glass is fixed, or thanks to laminated glass triplex;
• shockproof double-glazed windows withstand severe mechanical stress, prevent hacking, and if they break, then the fragments do not have sharp edges and are held by the film. These properties were achieved through the use of triplex glasses, which, recall, also provide excellent sound insulation and can delay ultraviolet radiation.

Some manufacturers offer even more modern and “smart” double-glazed windows. So, for example, they invented in Japan dirt repellent coatingdue to which there is no need to constantly clean windows, and this is a significant savings when it comes to high-rise buildings. Dirt almost does not stick to such glass; under the influence of sunlight, it is destroyed and washed off by rain water.

Some manufacturers offer double-glazed windows that make it easy to change the level of transparency of glass and if necessary turn it into mattto shield yourself from prying eyes outside. To solve the problem of ice formation, double-glazed windows with electric heating. The heating of the glass makes the snow and ice melt, and at the same time acts as an additional source of heat in the apartment.

In addition, today you can choose double-glazed windows with decorative glassesthat can have any desired color or even imitate stained glass drawing. Such products are made on an individual project.

Number 4. Glass spacing and soundproofing

Modern double-glazed windows can effectively solve not only the issues of thermal insulation, but also the absorption of street noise. Urban residents should appreciate this property.

Soundproofing characteristics depend on such parameters:

• double-glazed window width and number of cameras;
• distance between glasses;
• glass thickness and a combination of glasses of different thicknesses;
• type of glass.

The wider the glass unit, the better its sound insulation, and a two-chamber double-glazed window with a width of 42 mm will be much "quieter" than a two-chamber double-glazed window with a width of 28 mm. When the camera is increased by 3 mm, sound insulation grows by an average of 10%, and a two-chamber double-glazed window is already 40-45% more effective in terms of sound insulation than single-chamber. At the same time, the thermal insulation characteristics increase with an increase in the chamber to 16 mm, stabilize in the interval 16-24 mm, and then deteriorate due to convective heat transfer.

Distance between glasses should not be more than 20 mm, but, as a rule, it is 6-16 mm, and the more glasses are used, the smaller the distance between them, since the total width of the glass should not exceed 60 mm. And then manufacturers go to the trick, and do cameras of different thickness, trying to break the symmetry of the system leading to resonance.

An excellent effect in terms of sound insulation has the use of glasses of different thicknesses. When a sound wave collides with barriers of the same properties (glass of the same thickness), it easily passes through them. If the barriers have different parameters, then the sound wave will be more complicated, and it will lose a huge part of the energy. Glasses of different thicknesses do not resonate and make the apartment quieter by about 30%. In a double-glazed window only one glass should be 6 mm thick, let the rest be ordinary, 4 mm thick so that the structure would not be overstretched.

If, plus everything, you use triplex glass in the double-glazed window, which damps noise well, then you can achieve the highest results.

No. 5. Type of filling of double-glazed windows cameras

The glass pane chamber can be filled with one of the following gases:

• drained air - the most common and most affordable option;
• argon It has a higher dynamic viscosity and prevents convection between the glasses, so a double-glazed window filled with argon is about 1.4 times warmer than usual. In addition, argon protects the coating of i-glasses and is the best option for value for money;
• other inert gases, in particular krypton and xenon, have more outstanding heat-insulating properties and are “warmer” than air by 2.6 and 4.4 times, respectively, but such filling of the chambers is very expensive, therefore it is not used today.

A promising area is production double-glazed windows with vacuum inside. The vacuum does not conduct heat at all, therefore it will provide maximum thermal insulation, but only the manufacture of such double-glazed windows differs in a number of technical difficulties, therefore it pours a lot of money and is not widely used.

No. 6. Distance frame

On a remote frame in a double-glazed window literally everything keeps. She holds the glass and sets the required distance between them. It is better to choose a double-glazed window with not aluminum frame, but steel, because its thermal conductivity is lower, but even better is a full fiberglass or plastic frame.

Glasses are connected to the distance frame by sealants based on butyl and thiocol, which isolate the entire structure and give it the necessary physical properties. Virtually all well-known manufacturers of double-glazed windows use a similar method of joining, but there are also unfortunate companies who glue the entire “pie” with double-sided tape.

Additionally, thin decorative frames can be installed inside, which form an interesting layout.

Number 7. How to read a double-glazed window formula?

The characteristics of a double-glazed window are often given in the form of a formula that it would be nice to be able to read correctly so as not to fall into possible tricks of sellers. The formula is presented in the form “glass thickness and its type — chamber thickness and its filler — glass thickness and type ...”, and they begin with an external (facing the street) glass.

For instance, double-glazed window, which is described by the formula 6M1-16-4M1-12Ar-4I, consists of three glasses and two chambers.The outer glass is ordinary and has a thickness of 6 mm, then comes a chamber filled with air 16 mm thick, then a regular glass 4 mm, a 12 mm chamber filled with argon and a low-emission i-glass 4 mm thick. Such a double-glazed window will perfectly retain heat and provide good sound insulation.

A specialist of a company that manufactures windows should choose the appropriate option, but it is best to be aware of such subtleties in order to choose the right double-glazed window.

Number 8. Double-glazed window and climate of the region

When choosing a double-glazed window, first of all, it is necessary to proceed from the weather outside the window and personal requirements put forward to the design. For warm regions, a single-chamber or single-chamber low-emission double-glazed window will be sufficient. In other cases, it is better to look towards two-chamber structures.

Each type of double-glazed window is characterized by its indicator of heat transfer resistance: in a conventional single-chamber this indicator is at the level of 0.3-0.37 m²* C / W, and for a wide two-chamber - already 0.5-0.62 m²* C / W. In order not to overpay, it is important to consider the real needs for heat saving. So, for example, for the Moscow region, according to building codes, it is better to use window blocks with a heat transfer resistance of at least 0.55 m²* C / W. This requirement corresponds to a two-chamber ordinary double-glazed window and a single-chamber with i-glass and argon filling.

In pursuit of quality double-glazed windows, do not forget about the profile: if it is thin, and there are cracks in the structure, then at home it will still be cold and noisy.

No. 9. What determines the cost of a double-glazed window?

A lot of factors affect the cost of a double-glazed window:

• glass type. Energy-saving, tinted, impact-resistant and other specialized glasses are more expensive than usual, but in some cases it is impossible to save;
• number of cameras and the total width of the glass. Often not wide enough double-glazed windows are inserted into cheap profiles with a thickness of 60-64 mm. Outwardly, everything looks beautiful and can be performed with high quality, but for severe winters this option is not suitable;
• gaswhich the cameras are filled with;
• fittings.

You can save on the purchase of a double-glazed window if carefully consider the requirements that are put forward to the window unit in each room. Companies often force customers to choose the same type of design for all windows, although often this is not necessary. For a bedroom, for example, noise isolation and thermal protection are important, and in the kitchen you can put far from the most “warm” and “quiet” window - it is important that it skillfully open both completely and slightly, and form a small gap. For the first floors, a tinted window or a tamper-resistant window will be appropriate.

However, it’s important not to overdo it with savings. Too cheap offers are immediately swept away, as well as frankly uncomfortable options. For example, a dull window unit will be inexpensive, but in operation it is inconvenient. On the other hand, too intrusive offers of the manager of expensive functions should also not be credible.

No. 10. Visual inspection

When the glass is ready, it is necessary to inspect it. There must be a marking informing of the production date and manufacturer, some companies assign each individual product an individual number. There should not be any chips and cracks, the glass should have a smooth smooth surface, and the double-glazed window should have the correct geometry. It does not bother to measure the diagonals of the structure and compare them: if there is a difference of more than 3 mm, we can talk about a poor-quality product.

Windows are installed for at least 10-15 years, therefore, when choosing them, it does not hurt to spend a little time collecting information and studying the market.