What is Double Glazing?

EN673 is the European standard of measuring a U-Value for glass that is used in a building. All glass companies in New Zealand need to provide the U-Value of their glass solutions in relation to EN673 so that consumers can make informed decisions on the thermal performance of their glass.

What is Double Glazing?

Double Glazing is when two panes of glass (separated by a layer of air), are used in a home’s window. This provides another layer of insulation for your home, decreasing heat loss through your windows.

In the past, windows were fitted with a single pane of glass, which proved to be a particularly efficient heat conductor.

Ongoing research has shown that adding a second pane of glass, with a sealed pocket of air (or gas) in the middle, dramatically reduces the loss of heat through windows.

The requirement for Double Glazed windows in new homes did not become compulsory until 2007, so there are still many NZ homes with inefficient single-pane windows. There are a couple of options for double glazing existing windows


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The Process of Double Glazing

Double glazed glass is usually contained within an insulated glass unit to protect the near-invisible Low E coating. It can also be paired with a wide range of glass options.

Watch how Double Glazed Glass is made at Viridian Glass

Free Online Glass Selector

Use our FREE online glass calculator to help you find the right glass for your windows.

Glass for windows can be tricky, especially when there are so many things to think about. At Viridian we love glass and have created a tool to help you select the right type based on you, your house and the environment you want to create

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