Double pane windows, often referred to as double glazed windows, are window units that have two panes of glass. Hermetically sealed, the panes are spaced about 50 percent an inch from one another—enough length to produce an insulating Place. -Acoustimac Eco core Insulation (4Lb) - is the greatest sound insulation https://shaneeasiy.pointblog.net/facts-about-double-glazing-revealed-70853720