Low E Glass

“Low E” is short for “Low Emissivity”, meaning that the glass does not absorb and re-radiate the heat like the old tinted glasses do. Instead, it reflects the summer heat back to the outside, but in the winter this same high performance glass keeps the heat inside.

Low E is the biggest revolution in energy saving windows since double pane insulated glass. Most Low E glasses used by the window manufacturers have 2 layers of silver applied on the interior of the outside pane of glass to accomplish this energy saving feat.

Low E coatings combined with double pane insulated glass brought approximately another 40% increase in energy efficiency, compared to insulated glass without the Low E coating, a drastic improvement for something that’s almost invisible! Using Low E enables both aluminum and vinyl windows to easily exceed new energy codes. Many Low E windows exceed the codes by so much that they earn an additional Energy Star rating.

One of the very latest innovations in Low E is offered by Cardinal, the glass supplier to such household names as Andersen, Pella, Marvin and Kolbe. It’s called Cardinal 366 and features 3 layers of energy saving silver instead of the more typical 2 layers. The bar has been raised once again, not only for energy savings, but for also blocking of the UV rays that are a major cause of fading of draperies, upholstery and fine floor coverings (95% blocking to be exact). The overall general comfort level of your home is actually improved by using a high quality glass such as Cardinal 366. It is now standard in all NT Windows. We expect other manufacturers to jump on that bandwagon soon because investing just a few dollars more in the windows they produce will bring a very significant improvement in their windows overall.

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