Infrared Camera and Low-E Glass Exhibit

All objects emit long wave infrared radiation in the form of heat. Ordinary glass is opaque to this radiation so it would seem that the heat would not be lost through it. However, while being opaque, it is also very absorbent, so a lot the heat strikes it is absorbed at the glass surface, conducted through the glass, and then lost on the other side.

Low-E (low emissivity) glass reflects a lot more of this heat than ordinary glass as demonstrated by the brighter image reflected from the Low-E glass (left side) in our exhibit.

Low-E glass can substantially lower your energy bills primarily by keeping heat inside the building. In addition, Low-E glass can improve your comfort by raising window surface temperatures in winter, and reducing draft.

HOT TIP

Windows with Low-E coatings may cost 10-15% more than traditional units, but their energy loss is reduced by 30-50%.

COLD FACT

Windows typically account for up to 25% of a building's heating and cooling requirements.

ECO WATCH

The average Low-E coating manufacturing plant produces enough windows each day to save 10,000 barrels of oil -- the daily output of a $500 million offshore oil drilling platform. But the Low-E plant costs about $5 million.

Energy-Efficient Windows

Unlike old fashioned single-pane windows, most modern windows are built using double panes of glass, low-conductivity frames, inert gas-filled spaces, special heat-reflective coatings and effective weather stripping to cut down the transfer of heat and infiltration of air. They maximize comfort while cutting down energy use.

To learn more about energy-efficient windows take a look at our window glazing systems fact sheet (PDF, 70 KB).