You’ve narrowed your search for replacement windows to gas-filled double pane windows. You have even done your research and determined that vinyl windows offer the best value for your money. Congratulations.

Have you thought about the spacer that is used to separate the glass? With an average of 25 days in Ohio at below freezing*, keeping the argon gas sealed in the glass is an important part of the window. Finding a window that does not conduct heat while sealing is important too.

You may have even made your decision to replace your old double-pane windows because it has aluminum spacers that were popular in the 1960s and 1970s. Good for you, you are ahead of the game because aluminum is a great conductor of heat, and therefore heat loss.

The temperature at the edge of the glass is an important factor when determining a good spacer. You are trying to avoid any chill at the edge, which can cause condensation on those cold Ohio days. After all, the average wind chill from December to February is minus 15 degrees*.

Many products have come on the market since the days of aluminum. One spacer material is steel. With a cross-sectional shape to the steel spacer conductivity was decreased, but not enough for Ohio weather. There are superior products on the market today that reduce heat conductivity, and backed by a manufacturing sealant to reduce the possibility of losing the gas between the panes.

One such product is called SolarGold, manufactured in Ohio for Ohio homes. The SolarGold spacer is 100% non-conductive, made from a high-density oxygenated silicon desiccant. It is 950 times less conductive than aluminum and 85 times less conductive than steel.

Temperature comparisons at Edge of the Glass Using Different Technologies. Temperature Test results based on 0° outside and 70° inside.

The SolarGold spacer has an impenetrable outer seal with a Mylar radiant vapor barrier sheathing that keeps moisture out and the argon gas in. The non-fail interior seal with UV-resistant acrylic adhesive is the same adhesive used on F14 fighter jets. The cushion-edge technology allows for flexes with expansion and contraction, yet has a memory to maintain its seal.

The attached chart offers a comparison between some of the modern popular spacers, starting with the aluminum spacer that is still prevalent in homes. The chart also displays the temperature at the edge of glass for a heat mirror and compares it to warm edge technology, which is a manufacturing process that shifts to a higher performance glazing in the window.

You can see how the spacer plays a major role in reducing condensation. This reduces moisture for a healthier home that is less prone to mold and mildew.

Part I: A Good Window Spacer Can Save on Energy Costs Part II: Efficient Window Glass and the Air Between Part III: The Window Frame Can Save Energy Too

* Source: Data for Columbus, Ohio. Years 1999-2003, from the National Climatic Data Center