Thermal Insulation with Double Glazed glasses
Thermal insulation is a very important aspect which has to be thought about when putting an air conditioner or heater in a room. Significant amount of heat is exchanged with the outside environment through walls and windows and the best way to improve air conditioner or heater efficiency is by putting right thermal insulation in the room.
Double glazed glass or Insulated glass is the best way to protect heat loss through windows. A double glazed glass is a combination of two or more panes of glass with a space in between filled with air or gas (diagram below). The layers of glass and the air in between provide resistance to the flow of heat there by reducing the loss of heat generated by a heater or entry of solar heat from outside while air conditioner is on. It lowers the U factor as well as the solar heat gain coefficient as mentioned in the link.
Double Glazed Glass: source Wikipedia
During extreme summers or winters, sitting close to a window is difficult if the windows do not use double glazed glass. But double glazed glass can provide increased comfort near the windows. These glasses can greatly improve efficiency of air conditioner and heater and can thus bring down the units consumed on your electricity bills.
Additionally double glazed glasses also provides insulation from sound and thus if your house or office is close to airport, railways, or road, then these glass can help reduce the sound level as it also reduces the sound transmission. These glasses are perfectly transparent and in no way obstruct the visibility outside. For more details you can refer to Glazette which is India’s leading glass portal.