Low-E 240 vs Low-E 366 Window Glass

Low-E 240 vs Low-E 366 Window Glass

Low-E windows, or low-emissivity windows, have a coating on the glass that has changed rapidly over the past few years. There are many types of Low-E windows but not all Low-E glass coatings are created equal. Advances in technology have helped create a variety of Low-E glass types. In this post, we’ll compare Low-E 240 vs Low-E 366 glass.

These two types of Low-E glass in particular - Low-E 240 glass and Low-E 366 glass - offer many benefits that offer your home improved energy-efficiency and cost savings. Read on to see the key differences between these types of window glass.

What Does Low-E Mean?

Low-E window glass is glass with a low level of emissivity, also known as the ability of a material to emit energy as thermal radiation. By utilizing a thin, transparent coat, Low-E window glass reflects heat while allowing as much natural light as possible to pass through the window itself. Low-E also means that a house’s temperature can consistently reflect the interior temperatures inside while blocking exterior temperatures from passing through the glass (for a broader explanation, see our post on Low-E Window Glass).

What is Low-E 240?

When window glass glare is your top priority, Low-E 240 glass should be your Low-E glass of choice. A specially treated version of Low-E, this type of window glass is the best at controlling glare regardless of the level of light coming into your home. 

Low-E 240 glass also:

  • Helps your rooms maintain thermal comfort year-round
  • Blocks solar heat from entering your home
  • Keeps inside glass temperatures warm during the wintertime

As a reminder, Low-E glass is not a tint. Tinted glass works by absorbing sunlight and becomes hot in the sunlight. Low-E 240 glass coating is applied to clear glass, which results in a consistent appearance and performance of the coating regardless of the thickness of the glass.

Learn More About Low-E 240 Glass From The Experts At Cardinal Glass Industries↗

What is Low-E 366?

On the contrary, Low-E 366 is known in circles as one of the premier performance types of Low-E glasses. Low-E 366 glass provides some of the highest levels of comfort all year-round while simultaneously delivering some of the biggest energy savings. 

Low-E 366 glass also:

  • Offers solar control and high visibility
  • Is ENERGY STAR compliant in any zone when used in double-pane windows
  • Has a low solar heat gain coefficient (SHGC)
  • Blocks 95% of the sun’s ultraviolet rays

Cardinal’s Low-E 366 solar control and visibility capabilities have set a new standard in visual and energy performance. If you’re looking for a premium product for the highest-performance coating in Low-E windows, look no further than the Low-E 366 glass type.

Learn More About Low-E 366 Glass From The Experts At Cardinal Glass Industries↗

Is Low-E 240 or Low-E 366 Better?

Like other homeowner decisions, deciding between Low-E 240 or Low-E 366 depends on what your priorities are for your low-emissivity glass. 

  • Choose Low-E if your priority is reducing glare
  • Choose Low-E 366 if your focus is on energy savings overall

Both Low-E 240 and Low-E 366 offer incredible value and your decision will ultimately depend on your priorities and budget. Low-E 366 does offer a higher overall value. If you’re installing Low-E glass on just a few windows, making the investment in Low-E 366 might be best as it maximizes stopping UV and other harmful infrared rays.

If you’re looking to add an extra layer of protection or safety to your windows, Low-E windows could be the best option for you. Your windows provide so much for your home, and knowing the benefits and value of something like the Low-E glass coating could make the decision for how to best design your windows based on your budget. 

Learn more about energy-efficient windows by checking out our related posts below. Homeowners in North Texas interested in replacement windows are also welcome to explore our product options or schedule a free consultation with one of pros.


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