Advanced Technology

Multiple panes improve the energy efficiency of newer windows, but adding other technology is necessary to achieve maximum efficiency. When Low-E coatings, gas fills, warm edge spacer systems and improved framing material are used, more than two panes (triple pane) are rarely necessary, except in extreme climates. Additional panes may be desirable if you live on a busy street or for higher impact resistance.

The Heart

The heart of any replacement window is the type of glass that is used. The glass plays a large role in the overall energy efficiency, glare value, rate of furniture fading, the amount of natural light that comes into your home and the clarity of the view.

Low-e Glass

Low-emissivity (low-e) glass is the minimal quality you should consider. A microscopically thin, invisible low-e coating keeps heat indoors during the winter and heat outdoors during the summer. The low-e coating sometimes makes the windows slightly reflective, but it is barely noticeable.

There are three types of low-e coatings: High Solar Gain "Low-E", Moderate Solar Gain "Low-E" and Low Solar Gain "Low-E". With either type, the low-e coating is applied on the protected glass surface facing the air gap. Whether it should be placed on the indoor or outdoor pane depends on your climate.

Gas Fill

Argon and Krypton are both dense gases commonly used to fill the dead air space between the two panes of glass. These gases make good candidates for this application since they are inert and do not react with cold air effectively insulating the panes and keeping your home warmer in the winter. Argon and Krypton gas filled windows also tend to be better at soundproofing than units manufactured without the gas.

What Not to Consider

Insulated or "double-pane" glass can be found in both residential and business construction. It is required by building codes in many areas as a mandatory energy conservation measure. And it really makes sense because single pane glass has virtually NO insulating value.