The Purpose of Argon in Windows

Window Construction

• Modern residential windows are usually double-glazed. A single frame -- sash or casement -- contains two pieces of glass with a space between them. The space is vacuum sealed because a vacuumed space is a better insulator than air. Optional window muntins or spacers can also be installed between the panes of glass. Muntins on the inside and outside faces of the windows further create the illusion of divided lites.

Argon

• Argon often is installed inside the sealed space between the glazing. Just as a vacuumed space is a better insulator than air, argon gas is a better insulator than a vacuumed space. The gas further slows the transfer of heat from the inside of the window to the outside.

Increasing Efficiency

• You can enhance the efficiency of your new windows by opting for low-e -- low emissivity -- and UV-filtering films. A low-e coating filters infrared radiation -- or heat -- keeping the sun from heating the house in summer and preventing heat loss in winter. The UV film filters out ultraviolet light and reduces the damage sunlight can do to interior fabrics, artwork and surfaces.

Considerations

• While all of these energy-saving bells and whistles come at a price, they can significantly reduce heating and cooling costs. Every new window has an EPA label rating the energy efficiency of the unit. Argon gas can be a factor in making a window qualify for federal or state energy credits that reduce the cost of your project.