What Makes a Window Energy-Efficient?

Energy-Efficient Windows Begin with the Right Glass Pack.

An Insulated Glass (IG) Unit contains two or three panes of glass separated by a spacer. The IG Unit is also known as a glass pack. The glass pack contains panes of glass, warm-edge spacers, gas fill, and Low E glass coatings that all work together to improve the energy efficiency of a window.  These key elements are unpacked below.

• Panes of Glass – Newer windows are typically double pane or triple pane, which means they have either two or three panes of glass. Talk to your Window Source design consultant to determine the right number of panes needed for your region and home improvement goals.
• Warm Edge Spacers – Spacers separate and secure the panes of glass. The edges of the glass pack are the most vulnerable to heat and cooling loss. Warm edge spacers reduce conductivity or the rate at which heat passes through a specific construction material.
• Gas Fill – These non-toxic, inert gasses can be used instead of air between panes of glass to increase insulation and energy efficiency. Using Argon or Krypton in-between the panes of glass, makes it more difficult for heat or cold to transfer through the glass pack.
• Low-E Glass Coatings – As a microscopically thin, virtually invisible metallic layer deposited on the glass surface, Low-E Glass coatings reduce solar heat gain and give excellent protection against fading which can occur from UV rays. If your furniture or carpet is losing its rich color due to its proximity to windows, consider adding Low-E coatings.