Why does Vacuum Insulated Glass have a Getter?

What is Vacuum Insulated Glass and why does it need a Getter?

Vacuum Insulated Glass (VIG) is one of the most efficient and attractive glazing technologies available today. But if you’ve come across the term “getter,” you might be wondering what it means and why it matters. In this blog, we’ll explain what Vacuum Insulated Glass is, how it works, and why a getter is a crucial part of its performance.

What is Vacuum Insulated Glass?

Vacuum Insulated Glass is a highly advanced form of double glazing. Like traditional double glazing, it’s made from two panes of glass separated by a cavity. However, instead of filling this cavity with air or gas, VIG removes all the air to create a vacuum.

This vacuum prevents heat and sound from passing through, making the window significantly more efficient. The technology was first developed in Japan to reduce the weight of glazing in buildings located in earthquake-prone areas, while still maintaining high thermal performance. Since then, it has been refined to offer exceptional energy efficiency, durability, and aesthetics.

To understand more about how vacuum glazing works, check out our detailed introduction: What is Vacuum Glazing?

Why Is Vacuum Glass Better Than Standard Double Glazing?

Vacuum Insulated Glass has two key advantages:

  • Superior insulation: Because heat and sound cannot pass through a vacuum, VIG delivers much better thermal and acoustic performance than gas-filled units.
  • Slimmer profile: The vacuum cavity is typically just 0.3 mm wide, compared to 16–26 mm in conventional double glazing. This means the glass unit is slimmer, lighter, and more aesthetically similar to traditional single glazing.

That’s why vacuum glazing is an ideal choice for heritage window projects, especially in listed buildings or conservation areas where slim sightlines and minimal visual impact are essential.

You can also see a real-world example in our South Derbyshire case study.

What Is a Getter and Why Does VIG Need One?

A getter is a material placed inside the vacuum cavity to help maintain its integrity. Although the vacuum sealing process removes nearly all gas and moisture, some residual elements may remain. Over time, these traces can affect performance unless they are neutralised.

The getter continuously absorbs any leftover or leaking gases, keeping the vacuum clean and stable. A purer vacuum means better insulation and longer-lasting performance.

There are several types of getters:

  • Vapourised getters use reactive metals like tantalum or zirconium. These react with gas molecules and form thin films.
  • Non-evaporable getters, used in vacuum glazing, absorb gas without creating condensation. These are more stable and suitable for long-term applications.
  • Temperature-controlled getters work at specific ranges. For windows, low-temperature getters are ideal, as they function effectively at room temperature.

Without a getter, the vacuum would degrade over time, reducing the efficiency of the glass unit.

How Much Can VIG Improve Energy Efficiency?

Vacuum Insulated Glass is one of the most effective ways to cut energy loss through your windows. In well-insulated homes, especially those meeting Passive House or EnerPHit standards, vacuum glazing can contribute to a reduction in heating requirements by up to 75%.

Even in traditional or older buildings, retrofitting with VIG can make a significant impact. It not only reduces your energy bills but also improves comfort levels by maintaining consistent indoor temperatures.

To explore more on this topic, read Why Vacuum Double Glazing Is Best for a Passive House Window and What’s the Best Vacuum Glass on the Market?

Is Vacuum Insulated Glass Worth It?

Absolutely. While the initial investment is higher than for standard double glazing, the long-term benefits are clear:

  • Lower heating and cooling bills
  • Reduced environmental impact
  • Better aesthetics (especially in listed buildings)
  • Longer lifespan with minimal maintenance

VIG is especially useful in projects that require the look of single glazing without compromising on modern performance. These projects often require Heritage Windows to meet planning regulations, and vacuum glazing fits the bill perfectly.

You can also learn more about the technology from: www.vacuumglazing.co.uk

In summary: Vacuum Insulated Glass offers a powerful combination of aesthetics, performance, and sustainability. With the help of a getter, VIG maintains a long-lasting vacuum for consistent energy efficiency. Whether you’re renovating a period property or building a modern home, it’s a smart investment for your future.