Since the introduction of the insulating glass unit (IGU), there have been steady advancements in window assemblies that improve a home’s thermal performance.

You walk in a window showroom, and start talking to a salesperson about energy efficiency. He explains all the advantages and intricacies of the IG unit to you. If you are like most of us, he has lost you already with that acronym. IG stands for insulating glass and it’s what keeps the heat from coming in through your window in the summer and the cold out in the winter.

So what is insulating glass?  Insulating glass refers to glass that is made to prevent significant heat transfer into or out of a home or building. It consists of multiple pieces of glass separated by spacers made of either metal, such as aluminum, or structural foam. The space between the glass is sometimes filled with a noble gas, such as argon or krypton. Insulating glass is often abbreviated IG and is sometimes called double-glazed or double-pane glass. As technology evolves, triple-paned or quadruple-paned glass is now available as well.

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