Double Glazed & Triple Glazed Windows – Why Are They Important?

Double Glazed & Triple Glazed Windows – Why Are They Important?

January 20, 2020
By:
Martin Whitmore, President of US Window & Door
Energy efficient triple pane

What is energy-efficiency?

The idea of energy-efficiency is centered on two main points: namely that the object or product (in this case, the window) implement simple but elegant technological elements that work together to help  conserve energy, and that these elements work together to save the customer money. In terms of windows, this is accomplished in a number of ways; In accomplishing the tasks of any other energy-efficient product, energy-efficient windows also serve an additional purpose which is to help to protect the interior of the home or other building from the harmful effects of long-term sun exposure.

What makes a window energy-efficient?

So how does one make a window energy-efficient? To answer this is relatively simple, though the methods are highly advanced and well thought out. Energy-efficient windows vary in the ways that they achieve their energy-efficient status; in general, what makes a window energy-efficient has to do with one or some combination of the following factors: the frame material, any specialized coatings applied to the glass panels, and the number of glass panels in each window.

Why is it so important for me to consider purchasing energy-efficient windows?

The answer is simple: to save money. It is more or less a universal truth that you get what you pay for. As a result, you will naturally pay more money for a better product; but that is precisely the point. A better product will last longer and serve its purpose far more effectively than its cheaper alternative. And when you are choosing something for your home,

whether it is new construction or an existing home that you are remodeling, you will naturally want to choose the best of all possible options, while also saving money when  you can. Energy-efficient windows can save you upwards of $400 on your energy bill and keep your home more comfortable throughout the year. Keeping these things in mind, why wouldn’t you choose to have energy-efficient windows installed in your home?

What this article seeks to accomplish:

The principal purpose of this article will be to educate the reader regarding the importance of considering the purchase of energy-efficient windows, specifically those which achieve their energy-efficient status by the number of glass panels in a window. The article will focus mainly on the benefits specifically dependent on the number of glass panels in a window, that is, on the benefits and components of double- and triple-glazed windows.

What does it mean for a window to be “double-glazed” or “triple-glazed?

The term “glazed,” as it pertains to windows, owes its etymology to the Proto-Germanic word for “made of glass,” glasinaz. Essentially, this means that double-glazed means “double-glassed”. Double-glazed windows are so-called because, unlike traditional windows made with single panels of glass, they have two layers of glass. Obviously, triple-glazed windows are in the same vein, but they have three panels of glass in each window.

As modern as this idea might seem, double- and triple-glazed windows have been around for quite a while. The concept was originally thought up in the late 1800s. The concept didn’t catch on in full until the early 1900s. Over time the practical execution of the idea was developed into the technological marvel that it is today. The point is, as modern as it seems, using more than one panel of glass per window for the purpose of insulation is not a new idea, and at this point, double- and triple-glazed windows are far more common than you might think. It’s only a matter of time before they are truly a standard.

How do double- and triple-glazed windows work? What are its components?

Moisture is an important issue to consider regarding multi-glazed windows. Not only is moisture inside a multi-glazed window unsightly and impossible to properly clean, but it can also facilitate mold and mildew, which can cause serious health issues. Because of this, it is essential that moisture inside the window be eliminated.

To combat this issue, most double-glazed windows these days are fitted with an aluminum spacer between the two panels of glass. The spacer, in turn, is fitted with what is called a desiccant, which is a substance used to absorb moisture. The spacer with the desiccant is sealed between the window panels so that moisture does not make it into the window in the first place, and the desiccant is a safety net for that eventuality. The metal used for the spacer also helps insulate the window as a whole.

More recently, the spacers in energy-efficient windows that have two or more layers of glass for better insulation are made using stainless steel, as opposed to aluminum. The reason for this is that stainless steel is more dense than aluminum, and so is a less efficient conductor of heat and cold than aluminum is. As a result, it makes for far better insulating properties in the window. Aluminum can still be used as a spacer material, and when this is the case, the aluminum is often enhanced by being alloyed with other materials to enhance its thermal insulating capacity. In addition, most energy-efficient windows – especially those with vinyl frames – are constructed with specially-designed air pockets inside to better control the flow of thermal energy through the frame.

Why is the space between the panels so important, and what good does it do to have multiple panels of glass?

The reason for having multiple panes of glass in each window with space between is for the insulation of the window. It is especially important in the case of modern double-glazed windows because the spaces in these windows are filled with a colorless, odorless and harmless gas that is denser than air to help in the insulation process.

Specifically, the gases used are called argon and krypton, and they are used either together or individually, depending on the situation. Argon is six times denser than air, and krypton is six times denser than argon. This is important because the denser a substance is, the longer it takes to heat it or cool it.

panes

This applies to solids, liquids, and gases. The particles are so close together that any transfer of energy will take more time, transferring to each subsequent particle in the substance. All of this is to say, krypton is by far the most effective gas to put in a multi-glazed window for insulation purposes due to its extremely high density. Argon, however, should not be dismissed as being inferior, as it is also highly effective and is less expensive. For a good middle-ground price, some may choose to use a mixture of both gases in their windows. By and large, however, krypton is generally put to better use in triple-glazed windows, since the panels are closer together and you can fit more krypton into a smaller space than you can with argon. Argon is most often used in double-glazed windows since it is less expensive and not quite so dense as krypton. Regardless of which gas is chosen, it can be said with certainty that the use of these gases has been a revolutionary advancement in the energy-efficient window industry.

If triple-glazed windows have one more panel of glass, why not choose them over double-glazed windows?

All in all, it’s a judgment call. You may choose to go with triple-glazed windows because they have one more panel and the better of two gases – and you wouldn’t be wrong to choose that option. You would not be wrong to choose the less expensive and it is still a highly effective double-glazed window. However, one thing has not yet been explained in this article, and that is the subject of window coatings. There are a few different kinds of window coatings, but the main one we will discuss here is what is called a low-emissivity (or “low-E”) coating. Low-emissivity coatings serve a number of purposes, but all serve the same central purpose, and that is to make the window more energy-efficient in general.

To explain it a little more thoroughly, low-E coatings block a high percentage of ultraviolet and infrared radiation that comes through your windows with the sunlight. Ultraviolet and infrared light (which we can not see with the naked eye), as well as visible light, can prove harmful not only to humans but to anything made of wood as well. Wood is highly photosensitive, meaning that light has astonishing effects on it. Visible light bleaches the wood itself, and infrared light affects the chemical makeup of most hardwood finishes, and all three kinds of light alter the color of your floors in a range of ways. Long-term exposure to ultraviolet radiation can also be harmful to humans, so a coating that protects against these three things is certainly something to give some serious thought into.

Aside from the harm that can come to your floors, furniture, and floor coverings due to these kinds of light, Ultraviolet and infrared light also have a more notable and immediate effect on the interior of your home. Infrared light carries heat with it, so we feel it more immediately. Infrared light transfers heat directly into your home through sunlight or from objects outside that exude heat and transfer some of their heat inside. Ultraviolet light causes objects to heat up and affect their chemical makeup without any immediate recognition.

It is then important for the sake of energy-efficiency and the long-term protection of the interior of your home to have windows with this kind of coating. Low-E coatings block both kinds of radiation, helping to keep the interior of your home cool in the summer as it blocks heat from the outside and keeps it warm in the winter, as it blocks heat from the inside.. In the case of 4th Surface low-E coatings, the amount of visible light is also limited to varying degrees, so the risk to your hardwood floors is further reduced. In addition, 4th Surface coatings make your double-glazed windows perform as efficiently as if they were triple-glazed windows, while also eliminating the additional reflectiveness in a triple-glazed window.

Conclusion

In conclusion, you may still choose to purchase triple-glazed windows for one or more reasons, but double-hung windows can still be just as effective and  less expensive than triple-glazed windows, especially when treated with 4th Surface low-E window coatings.

We hope this article has helped  educate you and direct you to the best choice of windows for your San Diego home. Thank you for choosing US Window & Door for your energy-efficient windows and doors.