Where heritage glass outclasses the new
BENGglas is the solution for monumental buildings that want to be ready for the future without changing their appearance. Where double glazing and triple glazing are often too thick or too heavy, BENGglas is so thin that it simply fits into the existing frames. And: BENGglas insulates up to three times better than double glazing (U up to 0.40). This way, you maintain the original appearance and save significantly on your energy bill.
Does your building have that characteristic drawn glass with waviness? There is now a smart solution for that. With BENGglas combined with special heritage glass, you retain the authentic look while still benefiting from today's insulation values.
- Fits in the existing frames
- Maximum insulation (up to U=0.40)
- Also possible with light or strong waviness in the glass
- Color-neutral or extra clear vacuum glass
- U-value tested by IFT Rosenheim (2025)

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Find a certified installer
BENGglas has an extensive network of over 150 certified installers across Europe, specializing in vacuum glass installations. This way, you’re always assured of a professional close to home! Want to get the best deal easily? Fill out our quote form and receive three competitive offers from the three nearest BENGglas dealers in your area!
BENGglas: the first step towards sustainably protected heritage
In old monuments, you often find single glazing or old-fashioned double glazing in the window frames. Do you want better insulation? Then you quickly think of double glazing or triple glazing. But that is thick glass, which often means you also have to replace your window frames. And that often means losing the character of your building. Or worse: sometimes it's not allowed at all because it's protected heritage. In short, making it more sustainable seems difficult.
BENGglas has the solution for monuments!
With only 8.3 mm thickness, our vacuum glass always fits in your existing frames. And the insulation? That goes much better: twice as good as triple glazing and even three times better than double glazing! Do you currently have single glazing (U=5.8) or old double glazing (U=2.8)? Then you make a gigantic leap forward.
You notice it immediately:
✓ A lower energy bill
✓ More comfort, less cold drafts, and significantly less noise from outside (-36 dB)
✓ Fits in the existing frames
✓ Maximum insulation (up to U=0.40)
✓ Twice the lifespan of standard insulating glass, up to 50 years
This way, your monument not only remains beautiful but also future-proof!
Heritage Glass: Authentic Charm, Modern Performance
Heritage glass is that slightly wavy glass you see in beautiful old buildings. This hand-drawn glass creates those subtle distortions that make historical windows so unique. Do you want to maintain that authentic look during renovation? Then BENGglas Monu or BENGglas Monu Restover is your solution. This way, you get the best of both worlds!
Prefer not to have a wavy surface for your monument?
Then choose BENGglas Extra Clear or BENGglas Single Coated!
BENGglas Monu with Restover
At BENGglas, we understand that heritage glass is sometimes the preferred choice. That’s why we offer two options: BENGglas Monu Restover (heavily drawn) or BENGglas Monu (lightly drawn).
✓ Heavily drawn glass (BENGglas Monu Restover): Especially suitable for houses built before 1930, featuring more pronounced waviness and a thicker profile.
✓ Lightly drawn glass (BENGglas Monu): Ideal for houses built from 1930 onwards, with a more subtle, gentle waviness.
Prefer glass without waviness for a heritage building?
Choose BENGglas Extra Clear or BENGglas Single Coated!
What you need to know before choosing BENGglas Monu Restover
BENGglas Monu Restover combines an authentic appearance with maximum insulation — perfect for heritage buildings where a strong wave in the glass is desired or required.
A few important points to consider before choosing:
- More fragile: The extra monumental counter pane is untempered glass, making it more delicate than other BENGglas types.
- Thicker: At 13.06 mm, BENGglas Monu Restover does not always fit into existing frames — so checking is essential. BENGglas Monu, BENGglas Extra Clear, and BENGglas Single Coated are all 8.3 mm thick, increasing the likelihood they will fit your frames.
- Higher in price: Due to the extra pane and special design, the cost is higher than BENGglas Monu, BENGglas Single Coated, or BENGglas Extra Clear.
- Heavier: Its increased weight may require stronger (and more expensive) hinges and locks.
Want top insulation without wavy or drawn glass?
BENGglas Extra Clear or BENGglas Single Coated are excellent alternatives.
Extra long warranty periods due to long lifespan
At BENGglas, we think ahead. Thanks to the expected lifespan of no less than 50 years, we offer you up to 20 years warranty— that's twice as long as with double glazing or triple glazing.
What is covered by the warranty?
- 20 years warranty on BENGglas Extra Clear, BENGglas Single Coated, BENGglas Monu
- 5 years warranty on BENGglas Monu Restover
Our warranty covers the free replacement of your pane(s) if they lose their insulating function within the warranty period. This way, you can be sure that you're in good hands for years.
Want to know more?
View the full warranty terms in ''documentation''.
Extra high subsidies for national monuments
Thanks to the Investment Subsidy for Sustainable Energy and Energy Saving (ISDE), you receive an attractive compensation for making your home more sustainable with BENG glass:
✓ € 25 per m² for replacing glass with BENG glass (Registration code: KA18780)
✓ € 111 per m² if you also replace the frames (Registration code: other)
✓ € 46 per m² for replacing glass with BENG glass in national monuments
+ Doubling of the amount with additional insulation measures, such as roof or floor insulation!
Are you unsure if your home is a national monument?
Visit RVO.nl for more information!
Are you an entrepreneur and want to make your business premises more sustainable?
With the energy investment deduction (EIA), you can benefit from a tax advantage that can amount to as much as 300 euros per m²! The investment must be at least 2,500 euros. Apply for the EIA subsidy within three months after installation via the eLoket of RVO.nl.
Get Up to €16/m² Back in Flanders
Do you live in Flanders? Then you may be eligible for the renovation premium when renovating your home or building. When you replace existing glass with BENGglas, you can receive up to €16 per m²!
Frequently asked questions
Why should I choose BENGglas?
BENGglas is not ordinary glass – it is a revolutionary solution for sustainable and future-proof building. Compared to standard insulation glass, BENGglas offers unique advantages that directly improve both your home and the climate.
- Superior insulation: with a U-value starting from 0.35 W/m²K, BENGglas is twice as effective as triple glazing (0.70) and even three times better than double glazing (1.10). This means significant energy savings and lower heating costs.
- Long lifespan: while traditional glass lasts an average of 25 years, BENGglas lasts up to 50 years. Produce once, less CO₂, and half a century of benefits!
- Sustainable and environmentally friendly: thanks to less material use (30% less glass than triple glazing), BENGglas saves thousands of tons of CO₂ annually. This way, you actively contribute to a cleaner planet.
- Light and thin: at only 8.3 mm thick, BENGglas fits in almost any existing frame and allows for lighter hardware, making construction sustainable and efficient.
- A true climate hero: if all of the Netherlands switches to BENGglas, we can save up to 4.1 megatons of CO₂ annually — that's equivalent to 170,000 car trips from Amsterdam to Paris! Moreover, the production of BENGglas alone results in 24,000 tons less CO₂ emissions per year.
- A smart investment in the future: less energy consumption, less maintenance, and a longer lifespan make BENGglas a choice that benefits you for years – for yourself and for future generations.
In short: with BENGglas you choose maximum energy efficiency, sustainability, and a smart investment in the future. Make a difference, for your home and for our planet.
How do I request a quote?
Under the heading ‘Dealers’, you will find an overview of all BENGglas dealers near you. Once you have contacted a dealer, they will prepare a quote for you. This quote includes both the glass and the necessary installation. If desired, additional work, such as painting, can also be included. This way, our dealers always offer a complete total solution.
All BENGglas dealers have sample panes, so you can view the glass and make an informed choice. Additionally, you are warmly welcome by appointment in our showroom to personally experience the possibilities.
Is there no dealer near you? Then ask your local glazier to contact BENGglas via info@bengproducts.nl.
How do I apply for a subsidy?
ISDE subsidy for individuals and businesses
Do you want to apply for the ISDE subsidy via RVO.nl? Then make sure you have the following items at hand:
- An invoice with a registration code, the contact details of the installation company, and the date of purchase and installation.
- Photos of the installation, plus proof of payment.
- The number of square meters of glass you have had installed (note: do not include extensions).
Important: you must submit your application within 24 months after installation.
EIA subsidy for business customers
Do you have a business? Then you must apply for the EIA subsidy within 3 months after installation via the eLoket of RVO.nl. Make sure you have everything ready on time so that you do not miss out on benefits.
Subsidy in Belgium
Do you live in Flanders? Then easily apply for your renovation premium via the online portal on Vlaanderen.be. You will need the certificate from your recognized contractor for this.
What is the warranty period of BENGglas?
At BENGglas, we think ahead. Thanks to the expected lifespan of no less than 50 years, we offer you up to 20 years warranty— that's twice as long as with HR++ or HR+++ glass.
What is covered by the warranty?
- 20 years warranty on our basic range, without extra applications
- 10 years warranty on our specials with extra applications.
- 5 years warranty on fire-resistant vacuum glass
What do we mean by extra applications:
- All products that fall under ''BENGglas specials'', including BENGglas Monu
- Hybrid vacuum glass
- Laminated vacuum glass
Our warranty covers the free re-delivery of your BENGglas pane(s) if they lose their insulating function within the warranty period. This way, you can be sure that you are well covered for years.
Want to know more?
Check the full warranty terms in our knowledge base.
References
Are you curious where vacuum glass is already being used? Check out our references and discover how BENGglas is applied in various projects – from monumental buildings and protected heritage to sustainable new constructions, canal houses, and sleek offices.
In this way, we help contribute pane by pane to energy-efficient buildings with reduced CO₂ emissions.

BENGglas in ‘The Art of Living’ with the sustainability of a 100-year-old building

BENGglas breathes new life into mill Woldzigt
