← Insulating glass units

Insulating glass unit

Also called IGU, double glazing, sealed unit, thermal pane

Two or more panes of glass sealed together around a gap that insulates.

An insulating glass unit, or IGU, is a sealed sandwich of glass. Two panes (or three, in triple glazing) are held apart by a spacer around the edge, and the gap between them is sealed and filled with dry air or gas. Still gas conducts heat much less than glass does, so the unit loses less heat than a single pane.

The unit is made in a factory and then set into the sash as if it were one thick piece of glass.

Edge of a double-glazed unit in section

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Insulating glass unit, edge in section

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