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What is laminated glazing used for ?
This type of glazing provides enhanced strength and ensures safety in the event of breakage. Its main purpose is to hold the glass in place when it breaks, preventing glass fragments from scattering and avoiding any risk of injury. It also delays break-ins and acts as a guardrail under certain conditions. This feature is made possible by the glass sheets being held together by films.
Find out more about Stop Choc products
How to calculate the weight of glazing ?
To calculate the weight of a window, there is a formula to apply: 2.5 kg / mm thickness / m².
For laminated paper, you must add the weight of the films, which is 0.42 kg/film/m².
For example, an 8 mm glass will weigh 20 kg/m² (8 x 2.5), while a 44² laminated glass will weigh 20.84 kg/m² (((4+4) x 2.5) + (2 x 0.42)).
How to calculate the thickness of insulating glass ?
To obtain the thickness of insulating glazing, you must add the thickness of the glass products to the thickness of the air gap (or air gaps for triple glazing).
For example, a 4/16/4 will measure 24 mm.
How to take measurements for glazing?
To properly measure your glass, you need to be able to remove the mastic or glazing beads from your window to get the exact measurements. All you have to do is measure the height and width of your glass.
Should thermal glazing automatically be fitted as double glazing ?
Yes, thermal glazing is automatically installed as double or triple glazing to ensure it fulfils its functions: providing good thermal insulation and therefore an optimal Ug coefficient, good light levels and controlled solar gain.
Is insulating glass made up of several panes of glass for its effectiveness against noise ?
VIT acoustic insulating glazing is composed of at least two panes of glass of different thicknesses to improve acoustic performance: each glass thickness reduces a different wavelength of noise. Standard or acoustically treated laminated glass (acoustic PVB) can also be used to further improve noise performance.
Visit our acoustic configurator to find your solution !
What is the role of solar control glazing ?
Solar control glazing helps control the level of heat entering your building in the summer and provides adequate light while preventing heat loss in the winter. This glazing is chosen based on the building’s exposure and your project. This glazing allows you to reduce energy consumption to air-condition your building and improve your living comfort.
Moreover, RE2020 came into force on the 1st January 2022 emphasizes this point! “The aim of this regulation is to prioritize energy efficiency and energy decarbonization, to reduce the carbon impact of building construction while ensuring comfort in case of high heat »
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How is the vacuum created in double glazing ?
There is no gap between the glasses!! This is simply a filling of Air or dehydrated Argon between the panes. The seal is then made with butyl then PU or silicone, in order to guarantee the glazing 10 years against moisture absorption under normal installation and exposure conditions.
Is triple glazing useful?
Triple glazing provides better thermal insulation: the Ug coefficient can reach 0.4 W/m²°K, whereas double glazing only reaches 1 or 0.9. However, it’s important to note that energy gains are reduced during mid-season, so the use of triple glazing should be assessed based on its overall performance (useful on the cold NORTH-facing sides, but questionable for other orientations).
Who is authorized to manufacture fire-resistant or fire-rated frames?
Contrary to common belief, no specific approval or authorization is required to manufacture fire-resistant or fire-rated joinery. However, this type of work must be carried out in strict compliance with the test reports, which we can provide, in order to respect wood dimensions, profile types, tolerances, use of appropriate seals, and so on.
This applies equally to wooden, steel, and aluminum frames.
You can find all of our test reports → HERE along with our STOP FIRE products that are either fire-rated (Pyrobel) or fire-resistant (Pyrobelite).
What is thermal breakage and how can you identify it?
Thermal breakage occurs when the temperature difference between two areas of the same glazing is too great. This causes uneven expansion between the two zones, leading to thermal glass breakage.
Thermal breakage can be caused by shadows (trees, awnings, buildings, etc.) or by objects placed too close to the glazing (solid spandrels, radiators, sofas, posters, etc.).
The use of JPI (Heat Soak Testing) can reduce the risk of thermal breakage, but the only way to avoid it completely is to use tempered glass, which is immune to this phenomenon.
Contact us or call us at 03 85 81 48 08, so we can determine the right glazing solution together using our recognized simulation software.
What are dB Rw and Rw+Ctr?
Sound insulation, expressed in dB (decibels), represents the glazing’s ability to block noise. The higher the value, the better the acoustic performance.
There are three main categories of sound insulation:
dB Rw: Ambient noise – this includes most common frequency ranges.
dB Ra: Pink noise – generated in laboratory conditions, focused on mid and high frequencies.
dB Rw+Ctr: Also called road traffic noise insulation (tr), this rating is specific to noise frequencies produced by road traffic (low and mid frequencies). It is particularly relevant for buildings located near roads, highways, or in urban areas.
Check the acoustic performance of our glazing using our configurator.
What is a RAL color chart?
A RAL color chart is a standardized color reference system.
We can provide you with a PDF version, but the color representation is only approximate, as it depends on your screen or printer settings. The best option is to purchase a physical RAL color chart, or to obtain one from a paint supplier, for example.
This RAL chart will help you choose colors for your VIT Paint lacquered glass, enamelled glass, or integrated glazing bars within insulating glass units.
Please note that for our products with decorative inserts, the colors do not correspond to any specific RAL shade. We recommend contacting a VIT advisor for more information, or requesting the specific color chart (Eurofilter or other).
The same applies to our VIT Print digital printing glass: we do not use RAL tones, but CMYK (Cyan-Magenta-Yellow-Black), which is standard in the printing industry.
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What is a 1B1 or 2B2 glass?
A 1B1 glass refers to a laminated glass with a PVB interlayer of nominal thickness 0.38mm, while a 2B2 glass has multiple 0.38mm PVB interlayers.
Tempered glass, on the other hand, is classified as 1C2.
You can find the detailed safety classifications here.
Do floor panels have an installation direction?
Yes! Floor panels are generally made up of 3 panes of glass: two identical ones and one thinner pane. The thinner pane should always be placed on top, as it acts as a wear layer — a kind of protective coating — which prevents mechanical performance degradation due to wear, scratches, etc.
This wear layer is always made of tempered glass.
Can condensation on glazing be considered a defect? And how can it be avoided?
Condensation must be assessed in two different cases: condensation on the inside or on the outside face of the glazing.
Condensation on the inside face of the building can result from:
Frequent condensation, even with insulating glazing, is usually a sign of insufficient heating, ventilation, or excessive humidity. Only addressing these conditions can significantly reduce it.
Condensation on the outer face of insulating glazing may be due to:
This phenomenon is typically seasonal and temporary, occurring mostly in the morning (morning dew) and disappearing within the first few hours of daylight. It may reveal temporary marks like suction cups, labels, dots, or any elements previously in contact with the glass. These temporary effects, visible under specific lighting, are not defects.
Sometimes, external condensation can be avoided or significantly reduced by installing the glazing in reverse (Low-E coating on the exterior) or by using a self-cleaning Activ layer on the exterior face. However, these solutions are not always effective.
What temperature can tempered glass withstand?
The maximum temperature resistance of tempered glass depends on several factors such as the glass quality, thickness, exposure duration, and thermal treatment during tempering. In general, tempered glass can withstand temperatures up to approximately 250°C without breaking or deforming.
In addition to general heat resistance, thermal breakage should also be considered — this occurs when there is a large temperature difference between a hot and a cold area on the same glass unit. This critical differential depends on the thickness and is summarized below:
| Tempered glass thickness | Temperature difference (+/- 5°) |
|---|---|
| 4 | 210 |
| 6 | 180 |
| 8 | 150 |
| 10 | 120 |
| 12 | 90 |
Thinner tempered glass is therefore less sensitive to temperature variations.
What is the benefit of tempered glass?
Tempered glass has several advantages over ordinary glass:
In which direction should burglar-resistant insulating glazing be installed?
Intuitively, most people would place the burglar-resistant glazing on the exterior side of the building, as close as possible to the intruder. This is often how it’s installed, but it’s not the optimal configuration.
In fact, during hot summer conditions, the interlayers of laminated glass become significantly more flexible than at room temperature, while in winter they become much stiffer and almost brittle. Tests for burglar-resistant, bullet-resistant, and balustrade laminated glazing are always carried out at room temperature (around 20°C).
In the case of insulating glazing with a float glass on the exterior and a burglar-resistant glass on the interior, the intruder must first break the float face, which will make noise and potentially injure or hinder them. The noise generated at the start of the break-in attempt may give more time for neighbors to alert the authorities, and the inner pane will be harder to breach as it’s closer to room temperature.
Additionally, it’s easier to find compatible solar control coatings for exterior glass, which are rarely available on burglar-resistant glass.
Therefore, the ideal configuration is to install the burglar-resistant pane on the **interior** side of the building.
What is CEKAL?
CEKAL is a French quality certification for insulating glazing.
The CEKAL certification ensures that insulating glass units meet strict standards in terms of thermal and acoustic performance, safety, quality, and durability. CEKAL-certified IGUs must comply with current French and European regulations.
It allows manufacturers to demonstrate the quality of their products and differentiate themselves from competitors. Consumers can therefore confidently choose high-quality insulating glass that meets their performance and safety needs.
What is the reference corner of a glazing unit?
Some insulating glass units are delivered with a label marked “Reference Corner.” This label is always placed near one of the corners.
It serves two main purposes:
When the IGU weighs more than 100 kg: the label identifies the bottom corner used during manufacturing to ensure perfect alignment between the two panes. If one pane is slightly longer (within tolerance), this avoids placing the entire load on a single edge, which could cause shear stress on the seal.
When multiple IGUs contain integrated glazing bars that must align across a façade or window series: the reference corner ensures that all units are installed the same way, guaranteeing perfect alignment of the glazing bars and avoiding the “Christmas tree effect.”
In all cases, the reference corner should be placed at the **bottom**, and always on the **same side** when glazing bars are present (e.g. bottom left).
At what altitude is pressure equalization required?
For double glazing: altitude compensation must be carried out if there is a difference of more than 900 meters between the manufacturing site and the installation site (i.e. above 1100 m for glazing manufactured at VIT, located at approximately 200 m altitude).
For triple glazing: compensation is required for a difference greater than 300 meters (i.e. above 500 m for glazing made at VIT).
However, in all cases, a calculation can be done to determine the stress on the edge seal. This can lead to not compensating units that exceed the altitude difference (e.g. large units), or compensating some that fall slightly below the threshold (e.g. small units, or those with a high L/W ratio).
In which direction should a glass floor panel be installed?
A laminated glass floor panel is always made up of at least two structural layers and one protective layer.
The structural components are generally thicker, while the protective layer is tempered glass, typically 6 mm thick.
This protective glass must always be installed on the **top surface** of the floor panel — it’s the part people walk on. It provides mechanical protection to the structural layers and resists wear, preventing long-term degradation or accidental damage (e.g. from dropping an object).
In which direction should a Low-E glazing be installed?
When installing a Low-Emissivity (Low-E) glazing, several factors must be considered: aesthetics, safety, energy efficiency, and function. Here are a few considerations:
Low-E glazing:
In summary, the orientation of Low-E glazing should be determined by a combination of functional, aesthetic, and energy-related factors specific to your project. It is recommended to consult a professional for tailored advice. In any case, the Ug value of the glazing remains the same, but the solar factor is slightly reduced when the Low-E coating is placed on the exterior side.
In which direction should solar control glazing be installed?
Unlike Low-E glass, solar control glazing **must** be installed with the coated face on the **outside** of the building, as it must always face the sun.
Installing it on the interior side would severely compromise its solar performance, cause overheating, and increase the risk of seal failure and thermal breakage.
What is the difference between thermal and chemical tempering for glazing?
Thermal and chemical tempering are two methods used to strengthen glass and improve its mechanical resistance. Here are the key differences:
1. Treatment process:
2. Result:
3. Applications:
In summary, both methods reinforce glass by creating surface compression, but they differ in technique, performance, and typical use cases.
In construction, and in our product range, glazing is almost exclusively **thermally tempered**.
Are there sizing charts for determining glazing composition based on surface area?
Yes, there are charts or standards that can be used to determine the composition of a glazing unit based on its surface area. These charts take into account various factors such as glass dimensions, glass thickness, glass type, thermal and acoustic requirements, as well as local regulations or applicable building codes.
Using these sizing charts can simplify the design process by providing recommendations based on technical data and specific calculations. However, the number of possible combinations is so vast that it is impossible to summarize everything in just a few tables.
Therefore, it is recommended to consult qualified professionals or contact glass manufacturers to obtain accurate information and tailored advice for determining the appropriate glazing composition based on surface area and the specific needs of your project.
Heat buildup and stress in glazing edge seals: causes, treatments, and prevention
Heat buildup and stress in the edge seal of glazing units can result from several factors and may negatively impact the integrity and longevity of the glass. Here are the common causes, treatments, and preventive measures:
Causes:
Treatments and prevention:
In summary, heat buildup and mechanical stress in glazing edge seals can stem from various causes. Proper design, professional installation, and regular maintenance are key to preventing these issues and ensuring the glazing’s long-term performance and durability.
What causes chemical incompatibilities with edge seals or butyl in double glazing?
Chemical incompatibilities with edge seals in double-glazed units — especially those using butyl — can arise from several factors:
In summary, chemical incompatibilities with edge seals or butyl in double-glazing may result from chemical reactions, material incompatibility, environmental exposure, poor material quality, or flawed system design. It is therefore important to use compatible materials and monitor environmental and usage conditions to ensure seal longevity and effectiveness.
How to size a glazing unit (vertical, sloped, floor-mounted, etc.)
Sizing a glazing unit for a specific application depends on several factors, including the glass dimensions, the load it must bear, orientation, wind exposure, thermal and acoustic insulation requirements, and local building codes. Below are general steps to size glazing for different applications:
1. Determine the loads:
2. Consider orientation and exposure:
3. Determine the dimensions:
4. Choose material and thickness:
5. Check standards and codes:
6. Hire qualified professionals:
In summary, properly sizing glazing requires a thorough analysis of loads, orientation, dimensions, materials, and applicable standards. Proper design and installation are essential to ensure long-term safety and performance.
What causes chemical incompatibility between certain products and interlayers in laminated glass?
Chemical incompatibilities between certain products and laminated glass interlayers may result from unwanted chemical reactions between the interlayer components and external substances. These reactions can damage or degrade the interlayer, compromising the integrity and performance of the laminated glass. Common causes include:
To avoid chemical incompatibilities and preserve laminated glass integrity, follow these precautions:
Do you offer products for joiners?
VIT offers a wide range of glazing products tailored to woodworking professionals: fire-resistant glazing
VIT Stop Fire, anti-burglary glazing
VIT Stop Choc, thermal insulation glazing
VIT Therm, switchable/privacy glazing
VIT Stop View, acoustic glazing
VIT Acoustic…
Do you offer products for interior fit-out specialists?
VIT offers a wide range of glazing solutions designed for interior fit-out professionals: shower glazing
VIT Shower, glazing with decorative inserts
VIT Insert, digital printing glazing
VIT Print, acoustic glazing
VIT Acoustic, fire-resistant or fire-rated glazing
VIT Stop Fire, balustrade glazing
VIT Stop Fall, lacquered glazing
VIT Paint… enabling full interior decoration and safety.
Do you offer products for façade contractors?
VIT provides a complete range of glazing products for building and façade professionals: double or triple glazing with solar control functionality (neutral or reflective)
VIT Perform, acoustic functionality
VIT Acoustic, thermal performance
VIT Therm, anti-burglary protection
VIT Stop Choc Plus, and fire-resistant or fire-rated glazing
VIT Stop Fire.
VIT also offers glazing compatible with VEC (structural silicone glazing), as well as large-format glass panels.
Do you offer products for partitioning professionals?
VIT offers a wide range of glazing solutions designed for partition specialists: sandblasted glass
VIT Sand, glass with decorative inserts
VIT Insert, laminated glass, tempered glass, acoustic glass, fire-resistant or fire-rated glass
VIT Stop Fire, anti-reflective glass
VIT Stop Reflect, switchable privacy glass
VIT Stop View, and glass with integrated blinds
VIT Line.
Do you offer products for veranda specialists?
VIT offers a wide range of glazing solutions tailored to construction professionals — and more specifically to veranda builders: anti-burglary glazing
VIT Stop Choc Plus, self-cleaning glass
VIT Self Clean, thermal insulation glazing
VIT Therm, insulating glazing, solar control glazing
VIT Perform, heated glass
VIT Heat, acoustic glazing
VIT Acoustic…
Do you offer products for architects?
VIT offers a wide range of glazing solutions for building professionals and architects: anti-limescale shower partition glass
VIT Shower Glass, glass with decorative inserts
VIT Insert, sandblasted glass
VIT Sand, digital printing glass
VIT Print, heated glass
VIT Heat, acoustic glazing
VIT Acoustic, thermal glazing, solar control glazing
VIT Perform, glass with integrated blinds
VIT Line, low-emissivity glass
VIT Therm, floor glazing
VIT Stop Gliss, fire-resistant glazing
VIT Stop Fire…
Do you offer products for industrial manufacturers?
VIT offers a wide range of glazing solutions tailored to the closure and industrial joinery sector: sandblasted glass
VIT Sand, double or triple insulating glazing, fire-resistant glass
VIT Stop Fire, acoustic glazing
VIT Acoustic, custom-made glazing, glazing with integrated muntins, digital printing glass
VIT Print…
Do you offer products for metalworkers?
VIT offers a wide range of glazing solutions tailored to metalworking professionals:
anti-slip glass VIT Stop Gliss, fire-resistant or fire-rated glass VIT Stop Fire, thermal insulation glass VIT Therm, acoustic glazing VIT Acoustic, anti-reflective glass VIT Stop Reflect, laminated safety glass for balustrades
VIT Stop Fall…
Do you offer products for glaziers?
VIT offers a wide range of glazing solutions tailored to building professionals and glaziers:
anti-limescale shower glass VIT Shower Glass, digital printing glass VIT Print, glass with decorative inserts VIT Insert, textured/relief glass VIT Relief, acoustic glass VIT Acoustic, thermal insulation glass VIT Therm, solar control glazing VIT Perform, floor glass, anti-reflective glass VIT Stop Reflect, safety glass for balustrades VIT Stop Fall…
What type of glazing should you choose for a facade ?
To ensure your glazing suits your façade perfectly, VIT offers a wide range of solutions tailored to building professionals !
The recommended façade glazing is selected based on thermal, acoustic, and safety performance. Indeed, façade glass serves multiple purposes in a building: both aesthetic and technical. It is therefore essential to choose Technical Glazing products that comply with current standards and regulations.
Note that solar control products from the VIT Sun range are frequently combined with safety glass from the VIT Protect range — such as Stop Choc and Stop Choc Plus.
Which glazing should you choose: single, double or triple?
Single glazing is used almost exclusively indoors, for example to create partitions using laminated glass, or for interior design features such as mirrors, splashbacks, lacquered glass, or shelves.
Double glazing is typically used on exterior applications, offering good thermal insulation. It also allows additional functions to be combined, such as solar control, acoustic insulation, or safety performance.
Triple glazing is mainly recommended to achieve very high thermal insulation (Ug < 0.9 W/m²·K). It is therefore often used on north-facing facades or at higher altitudes in cold regions (such as Savoie, Jura…).
What type of glazing protects against UV?
When UV protection is needed, laminated glass—whether rated 1B1 or 2B2—filters out 99.9% of ultraviolet rays responsible for the ageing of objects, discoloration, plastic degradation, and more. You can explore our VIT Protect range HERE.
Note : UV rays do not produce heat. Do not confuse UV protection with protection against solar heat ! To control solar energy gain, you need solar control glazing — take a closer look at our dedicated range here.
In which types of glazing is it not recommended to install an integrated blind?
Integrated blinds can be fitted in any type of insulating glazing, with or without a coating.
For exterior use, it’s important to adapt the slat color and/or the type of coating (solar control or low-emissivity) to limit heat buildup inside the insulating glazing.
Special attention should be paid to tilt-and-turn windows, as operating the blind while the sash is tilted can cause the slats to scratch the glass or the coating. This is particularly true for motorized blinds, which may be remotely activated and rise while rubbing against the glass without the user noticing.
In which types of glazing is it not recommended to install an integrated blind?
Classes such as 1B1, 2B2, etc., in the context of glazing, refer to the classification of glass according to its impact resistance and behavior when broken, based on European standards. These classes are defined by the European standard EN 12600, which specifies the mechanical resistance requirements for glass used in buildings.
Here’s what these classes generally mean:
Therefore, a class like 1B1 corresponds to basic impact-resistant glass that remains in place after breakage and retains fragments, while 2B2 refers to glass with enhanced impact resistance that also remains in place and effectively retains fragments. These classifications are essential to ensure that the glazing used in buildings meets safety and performance requirements specific to each application.
How to discover our VIT products ?
You can explore VIT insulating glazing products on our website by application, theme, or profession in our menu – Our products. This allows you to browse all our ranges of professional glazing according to your needs: thermal glazing, acoustic glazing, decorative glazing, or safety glazing (fire-resistant glazing, fireproof glazing)…
How to place an order for VIT glazing products?
To place an order for professional glazing, you can request a quote, contact a VIT expert, or log in to your client area. Everything can be done directly on our website under the “Our services” section.
How to get a quote for VIT products ?
To get a quote, click on request a quote and start your glazing project by filling out the form! A VIT advisor will get back to you as soon as possible. You can also contact us directly at 03 85 81 48 08
Does VIT sell spare parts?
VIT can provide you with installation accessories (hinges, locks, handles…) for your fully glazed doors (Clarit and Securit types) as well as for shower doors and partitions. We can also supply seals suitable for installing your glazing (insulating glass, floor panels…) and silicones compatible with our glazing products.
How can I track my orders/delivery of VIT products ?
To track your orders and deliveries, visit our website in the VIT LINK – Pro area section. Through this tab, and using your personal login details, you can access the tracking of your professional glazing orders in your dedicated customer account.
Does VIT provide installation assistance or on-site delivery with crane truck?
VIT can offer various delivery services:
Simply contact VIT to set up your project and specify that you would like this assistance.
How do I report a dispute, or a defective/non-compliant product ?
If you receive a defective glazing following an order from VIT, you can return it by filling out the following form. You can then give the defective glazing back to the delivery driver during their next visit. Once the glazing is returned, the defect will be analyzed, and replacement will be covered or not, depending on the origin of the issue.
How do I report breakage during delivery (terms and reporting period, etc.)?
Glass breakage during delivery can happen. If breakage occurs during delivery, you can report it directly on the delivery note in the presence of our driver. It will then be covered and the glazing will be remanufactured free of charge and delivered with your next shipment.
If the breakage is noticed after the driver has left, you can reorder the glazing as usual, by sending us a copy of the delivery note, for example, so we can relaunch the glazing in production. In this case, it will be invoiced.
How are labels applied to glazing?
There is no absolute rule for how labels are applied, especially on insulating glazing units: depending on production requirements, machine constraints, customer requests for glazing orientation on pallets, or the weight of the panes, labels can be placed on glass 1 or glass 2 (or 3 in the case of triple glazing).
However, for insulating glazing, there is always a note at the bottom of the label indicating on which pane it is placed. It is then up to the installer to determine the correct orientation during installation.
For example, solar control glazing must always be installed with the coated side facing outward, whereas Low-E glazing can be installed in either direction.