What is Vacuum Glazing?

Vacuum glazing is a cutting-edge window glass technology designed to provide superior thermal insulation compared to conventional double or triple glazing.

Vacuum glazing, also known as vacuum-insulating glazing (VIG), is a thermally insulated glass unit that consists of two pieces of glass that are hermetically sealed around the edges. All the air is evacuated prior to sealing, thus creating a vacuum. It is this vacuum, as well as a good low-E coated piece of glass, that creates exceptional thermal performance.

Vacuum glass is an excellent replacement for inefficient single glazing in sash windows, achieving better results than traditional double and triple glazed IGU’s due to the following key advantages.

Ultra-Thin Profile

Traditional double glazing units are typically 24mm or thicker, which can be too bulky for the narrow rebates of sash windows. Fineo vacuum glazing by AGC, however, is only 7.7mm thick, making it a perfect fit for heritage and period sash windows without altering their aesthetics.

Superior Thermal Insulation

Despite its thinness, vacuum glazing provides insulation equivalent to triple glazing. This is due to the vacuum layer between the panes, which eliminates conduction and convection heat transfer (more on that below). Fineo vacuum glazing can achieve a low U-value of 0.7 W/m²K, significantly reducing heat loss. Single glazing has a U-value of 5.8 W/m²K so when replaced with Fineo the impact on heat insulation and comfort levels is instantly noticeable.

Excellent Noise Reduction

The vacuum layer between the glass panes acts as a barrier against sound transmission. This makes vacuum glazing an effective solution for reducing external noise – ideal for homes in busy urban areas. Fineo can reduce perceived noise by 34% when compared to single glazing.

Minimise Condensation

Vacuum glass reduces the risk of condensation forming on the inside of windows, as the inner pane stays warmer compared to traditional double glazing. Ventilation will also play a big part in reducing internal condensation.

Lightweight

Compared to traditional double or triple glazing, Fineo vacuum glazing is much lighter. Therefore putting less strain on the sash window mechanisms. This means fewer modifications are needed to the existing frames and counterweights. It is also easier to install and meet building regulations for listed buildings.

Maintains Heritage Aesthetics

Many period and listed buildings require windows to retain their original appearance. Since Fineo is so thin, it allows homeowners to upgrade to modern insulation standards while preserving and restoring the historic timber sash window frames. This can be very important in conservation projects where building regulations must be adhered to.

Long Lifespan

High-quality vacuum glazing such as Fineo can last for 60+ years, with minimal risk of the gas leakage issues that affect traditional double glazing because of the vacuum gap. Fineo has a market leading 20 year warranty and is the only VIG to be manufactured in Europe and to come with CE marking.

Increased Energy Efficiency

By reducing heat loss and improving insulation, Fineo vacuum glass helps lower energy bills and contributes to a more sustainable property. Fineo is also manufactured in Europe by AGC where the glass is produced in as energy-efficient a process as possible. With sustainability at the forefront of all its glazing innovations.

The following table compares Fineo with traditional types of glazing;

To understand the magic behind vacuum glazing, let’s take a look at another, more familiar product, that uses a vacuum – a thermal flask. A thermal flask (or vacuum flask) retains heat by minimising heat transfer through three main mechanisms:

Insulation via Vacuum

• The flask has a double-walled structure with a vacuum between the walls.
• Since a vacuum has almost no air molecules, conduction and convection (which require a medium) are greatly reduced.

Reflective Inner Coating

• The inner surface of the walls is often coated with a reflective material (like silver).
• This helps to reflect infrared radiation back into the liquid, reducing radiative heat loss.

Tight-Sealing Lid

• The flask has a tight-fitting lid that prevents warm air from escaping and cold air from entering.
• This minimizes heat loss due to evaporation and convection.

These features work together to keep hot liquids hot and cold liquids cold for extended periods. But the exact same principles can be applied to glazing. Vacuum double glazing consists of the following features to apply those principles;

Two Glass Panes – Like traditional double-glazing, vacuum glazing has two sheets of glass. But instead of a gas filled cavity between the panes, there is a 0.1mm vacuum gap.

Vacuum-Sealed Gap – Unlike double-glazing, which uses gas (like argon or krypton) between the panes, vacuum glazing removes all the air, leaving a near-perfect vacuum. As the unit is hermetically sealed vacuum glazing can easily outlast traditional glazing, where the gas can leak.

Micro-Spacers – Tiny spacers (imperceptible to the naked eye at a regulated distance) keep the glass panes from touching each other, maintaining the vacuum gap. All vacuum glass has micro-pillars and the distance they can be noticed from is regulated, so that you don’t even notice them.

Edge Seals – The glass is hermetically sealed along the edges to maintain the vacuum for decades. Fineo has a warranty of 20 years, with a lifespan of 60+ years

Low-Emissivity Coatings – Fineo vacuum glazing includes a low-E coating to further reduce heat radiation, boosting performance.

Fineo vacuum glazing is can be easily applied to the following sectors:

Residential Homes – Energy-conscious homeowners are increasingly adopting vacuum glazing to reduce heating and cooling costs. Not only will Fineo reduce your energy bills and carbon footprint –but it will make your home far more comfortable without damaging the original aesthetic.

Heritage and Historic Buildings – Many older buildings cannot support the weight of triple glazing, making vacuum glazing an ideal retrofit solution. Fineo vacuum glazing also adheres to building regulations for listed buildings.

Commercial Buildings – Offices, hotels, and public buildings benefit from vacuum glazing’s thermal and acoustic insulation properties.

Greener Projects – Vacuum glazing like Fineo is being integrated into modern window projects where sustainability and the environment is as important as heat and acoustic insulation.

Vacuum glazing is more expensive than traditional double glazing, but the long lifespan and warranty, long-term energy savings, reduced heating and cooling costs, and potential increase in property value make vacuum glazing a strong argument for the investment. To get expert advice about your project contact us today for a free quote.

Fineo Vacuum Glazing Is A Step Towards a Greener Future

Vacuum glazing is more than just another window technology –it represents a major leap forward in sustainable building design. With its superior insulation, lightweight structure, and long lifespan, it’s only a matter of time before vacuum glazing becomes the standard for energy-efficient buildings worldwide. Fineo by AGC is at the forefront of this innovation. And as Fineo is the only vacuum glazing manufactured in Europe, with a 20 year warranty and CE marking make it an ideal solution to heritage and conservation projects.

To start your Fineo project today by getting in touch.

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