Choosing Triple Pane Windows
Is it really a given to state that all triple pane windows are energy efficient? Not quite. Triple glazed windows are a step up in performance, comfort and durability in windows from the standard double glazed windows that are offered as a typical window in Canada. A triple pane window consists of three panes of glass with spacers placed in between the panes. The window frame that holds the triple pane in place comes in different material options such as vinyl (PVC), aluminum, wood and fiberglass. Triple glazed windows usually have a larger glazing pocket than double pane windows giving added insulation to your home as well as better comfort value. They are also great for saving energy and are an exceptional solution for keeping the cold out and the comfortable temperatures inside. With all the great features and benefits of triple glazed windows, the question is: are all triple glazed windows the same?
The answer is no, they all differ from company to company. These are some of the factors to consider when looking for a quality triple glazed window that is built to outperform any other:
Choosing the right frame material is the most crucial aspect to consider in a window. Fiberglass frames are not only the most durable and long lasting, they are also the most energy efficient window material used in the industry. It is important to note that the stronger the frame is, the more weight the frame can hold without warping overtime. Due to the fact that a triple pane fiberglass window is heavier than a double pane, a strong frame is needed to successfully withstand the weight of a triple glazed window. If a PVC frame is used for a triple glazed window, the window will ultimately sag. Usually an aluminum or steel reinforcement would be used, but both materials are conductors, reducing the energy efficiency of the window. Triple pane adds approximately 3 pounds per square foot, demanding a strong frame material such as fiberglass with a design to support the heavy duty weight of a triple pane window. Fiberglass frames also come in two variations; open back and closed back. Closed back frames assure much more durability whereas an open back frame is more flimsy and gives much less support.
Type of Spacer UsedHaving a good quality spacer for triple pane windows is also an important factor to consider. The most common spacers used are the single seal spacers, warm edge spacer, and premium super spacer. The single seal spacer is made using enclosed laminated material and is applied with heat and compression, however it is not successful in achieving good insulation results. The warm edge spacer is good at maintaining its flexibility through weather changes and atmospheric temperatures. The premium super spacer is made from a superior quality silicone resistant to UV light oxidation. Unlike other spacers used such as warm edge spacers, the premium super spacer offers extreme durability and great argon gas retention in order to acquire high energy efficiency.
Read more about this: Glazing Options
Compound sealant is a material used to seal the sealed unit around the perimeter, joining to the back of the spacer. This compound is the main component to preserve the air-tightness of the sealed unit. Recent technology offers a sealant that ensures argon gas retention that is better than other conventional sealants used by many companies (i.e poly sulfide). Especially with triple pane windows, the sealant contributes to the overall strength of the window.
Gas fillsGas fillings are specific types of gas that are injected between the panes of glass in a window. Krypton gas and argon gas are two types of gases that are used for added thermal performance and each one has its benefits. Argon gas is used more often because it is cheaper than krypton gas as well as its heavier density than air, providing more thermal efficiency between the panes of glass. Krypton gas is a more expensive option, however it is also a better insulator than argon gas. Krypton gas also performs in a more effective manner than argon gas where there are small air gap spaces. Taking krypton gas’ price into consideration, argon gas is still a good option for triple pane windows that have a large air space.
Window energy ratingsGood triple pane windows should offer an insulating U value of around U-0.13 to U-0.18 with an SHGC of 0.60 to 0.65. Along with this, the air infiltration rate also must be taken into consideration. Air infiltration is the amount of air that leaks through the window. Infiltration leads to increased heating and cooling loads when an indoor space needs to be cooled or heated. Fiberglass products are the best to insure that the air infiltration rate stays the same over a long period of time.

I have a question. What is Fibertec’s percentage difference between triple pane and double pane?
I currently have quotes on double and triple pane for a well insulated home I am building but the triple pane cost is more that 40{a1e3408b28e349066677ffa6d2c9947b97125fce257a48f3930b2b2e7fae95d0} different from the double. I know triple pane has a much better U-value and comfort value but is it worth the 40{a1e3408b28e349066677ffa6d2c9947b97125fce257a48f3930b2b2e7fae95d0} upcharge?
Jeff
Hi Jeff,
Out triple pane pricing vs our double pane is around a 15{a1e3408b28e349066677ffa6d2c9947b97125fce257a48f3930b2b2e7fae95d0} difference. One of the reasons the cost difference between the two products is so low is because our closed back frame was designed to easily hold a triple pane unit. Other companies use a double pane frame and try to put a heavier triple pane unit inside the same frame design and they find that their service issues increase, therefore dissuading customers from using triple pane units by increasing the pricing. Good triple pane windows also use a larger glazing pocket and increase the insulation value from R.3.5 to R 7.1. Companies that use the same glazing pocket only increase the insulation from R 3.5 to R 4.5.
Fibertec Team
Hello. I found your website after the window guy at a local lumber store told me that triple-glazed is only available in casement windows and that the R-value improvement increases only a few points, because 3 panes are put in the same width space as the 2 would be in a double-glazed -that is, they contain more glass and less gas. I wanted triple-glazed, double-hung and side-sliding windows that give the true increased R-value -7 point something as I recall from your website. Is this possible? Is it advisable? The local guy said they would be too heavy to work. I thought the problem would be with casements, not the others.
Thanks,
Will
Hi Will,
We apologize for the long wait on a reply. In response to your inquiry, casements will give you a better energy rating than a sliding window or double hung due to the fact that you can increase the air space. The best way to increase the u-value of double hung tilt windows is to add krpypton because this gas usually works better in smaller spacers. When looking at the performance of a window, you must consider air infiltration as well. Any window that slides (double hung windows, side sliders) works on friction and will therefore have a poor air infiltration rate. Casement windows on the other hand are a compression sealing window and will give you a better air infiltration rate. Hope this answers your question.
Fibertec Windows and Doors
Hi, I had a few questions, and I was wondering if you can answer them. My first question is what is the average cost per window if it was triple glazed therefore making it R-value. Also, I was hoping you can provide me with your resources so I’m able to use the information her for my project. Finally, if I were to quote your information properly I’m required to state your name. so if you don’t mind this information would be very much of use. If you can get back to me as soon as possible that would be very much appreciated Thank You.
Hi Tiara,
Your questions are a little unclear. If you have any questions about our products feel free to email us at [email protected]
Thanks
Fibertec Windows and Doors
What are your recommendations for triple glazing that is also soundproof? Note that I am specifically excluding double glazing or laminated glass solutions which I am aware are more efficient for soundproofing, but are not as thermally efficient.
For example, one installer is suggesting to use 3 mm, 4 mm and 3 mm thick glass respectively in the sealed unit. What are the limits on the window frame? Is it possible to increase the thickness further, such as e.g. 3 mm – 6 mm – 3 mm?
Thank you
Hi Oliver,
It seems to me that you are on the right track for determining a good way to apply soundproofing for your new/replacement windows. You mentioned that you are excluding laminated glass, which actually yields good sound transmittance ratings. Even in the case of laminated glass, you could use different glass thicknesses to achieve soundproofing which will essentially break the sound waves as they travel through the glass. You can definitely increase the thickness to 6mm to achieve better STC ratings.
Fibertec Windows and Doors
I blog quite often and I really appreciate your information. This article has truly peaked my interest.
I will book mark your site and keep checking for
new information about once a week. I subscribed to your Feed as well.
Hi Chi,
Thank you very much. We hope you continue to read our future blog posts