Soundproof glass, also called acoustic glass or soundproof glazing, isn’t cheap and varies in cost depending on the specifications. However, you can expect to spend around $950 for a double-pane laminated glass window, plus the labor needed to install it. In contrast, soundproof polycarbonate panels like DefenseLite typically cost about $30-$75 per square foot to install. All DefenseLite panels are installed by trained and certified dealers and are covered under manufacturer warranty. Depending on the system, warranties range from a minimum of 2 years to up to 15 years.