How to Counter Heat Loss Through a Glass Window

Save on heating by beefing up windows.

Windows can be a major source of heat loss in winter, so making improvements to counter that will save you energy and money. Windows can be the least energy efficient part of the exterior of your home. Glass itself can lose heat, transmitting it to the outdoors, and if you have gaps or cracks around the window frame, a lot of heat can escape through them. Some fixes require extensive work and a bit of an investment, but others can be accomplished in just a few moments or with a few dollars. Evaluate the options to see what works for you, given your climate, budget, heating costs and time.

Things You'll Need

• Storm windows
• Caulk
• Weatherstripping
• Low emmisivity coating
• Window plastic kit

Instructions

1. Install storm windows, which is by far the most expensive and time consuming option to countering heat loss and also the most effective, short of replacing the window fixtures entirely.

2. Examine your windows and frames for a close fit of all panes and moving parts. If there are gaps in the sliding mechanisms or between the glass and frame, seal them with caulk or weatherstripping. Caulk and seal the window frame, which is a low-bore option, but one that will preserve a lot of heat if there are existing cracks or gaps of any kind.

3. Replace panes with glass with a low emmisivity coating. Not all glass is the same. A low emmisivity coating on the pane reduces the heat loss that occurs through the glass itself.

4. Put a seal of plastic around the window frame in colder months. A window frame well sealed with a plastic sheet creates an insulating barrier of air between your home and the outside. Air is one of the best insulators. You can find kits with easy-to-install fittings for this at your local hardware store.

5. Close your curtains during the nights, and open the curtains to south-facing windows during the day, effectively creating a passive solar set up in your home just by using the curtains.

References

• NFRC: WIndows and Heat Loss
• US Dept. of Energy: Windows