Weighing the costs and benefits of upgrading to triple-pane glass? We’ll walk you through what you need to know in order to make the best choice for your project.
In short, windows and doors made with triple-pane glass give you greater thermal and sound performance. Read on to understand more about the difference triple-pane glass makes and how it compares to standard dual-pane glass — plus, get to know your options.
Triple-pane and dual-pane glass are both types of insulated glass units (IGUs) available with our windows and doors. Here’s a side-by-side comparison of these two IGU options:
| What is it? | Pros | Cons | What else to know | What product lines have this option? |
|---|---|---|---|---|
| Dual-pane glass has two panes of glass and an air space in between. |
An argon-gas filled air space and up to two low-emissivity (Low-E) coatings improve the insulating ability of dual-pane glass. | Dual-pane glass is not as effective at reducing energy loss and sound transmission as triple-pane glass. | Dual-pane glass with a Low-E4® coating is a good choice in climates with both heating and cooling seasons. | Dual-pane glass is standard with all our window and door products. |
| Triple-pane glass has three panes of glass with two air spaces in between. |
Two argon-gas filled air spaces and up to three Low-E coatings make triple-pane glass the most insulating glass option. | Triple-pane glass is more expensive and heavier than dual-pane, increasing installation costs. | Triple-pane glass is most impactful in northern climates. |
Triple-pane glass is an option with the following: • E-Series, A-Series, and 400 Series windows and doors• Select 100 Series windows available starting Oct. 20 • Select 200 Series doors |
*Our windows can also be ordered air-filled as needed for various reasons, including to meet requirements in high-altitude locations.
The specific performance benefits of windows with triple-pane glass include:
The thermal performance of windows and doors is measured with U-Factor values. Looking at a window's U-Factor value will help you compare between manufacturers and understand if the performance will meet standards for various energy-efficient building programs.
It’s important to look at the U-Factor value for the entire window assembly — glass, frame, etc. — when assessing performance. To do this, look for the “whole unit” U-Factor value rather than the “center of glass” U-Factor value. It’s particularly important to look at U-Factor performance when you live in a cold climate because it will help you understand how well the unit will help keep in warm air during the winter. (In a hot climate, Solar Heat Gain Coefficient would be the thermal performance value to evaluate because it gives an indication of how well the unit will help keep the sun’s heat out).
Want to understand more about the difference between R-Value and U-Factor values?
The measures used to evaluate sound performance are sound transmission class (STC) and outdoor-to-indoor transmission class (OITC). A higher value indicates better sound reduction for both STC and OITC. We provide STC and OITC ratings through the testing we do — find performance documents.
The more coatings applied, the better the thermal performance will be. Low-E coatings can be applied to triple-pane glass in various ways. Here’s what you should know:
Standard triple-pane glass options include one surface with a Low-E coating. These are our standard glass coating options:
Enhanced triple-pane glass options include two surfaces with Low-E coatings, which further enhances thermal performance. Here are some combinations to be aware of:
Enhanced triple-pane glass options with HeatLock® technology allow for three panes to be coated with a combination of two of our “soft” coatings — Low-E4, SmartSun, Passive Sun, and Sun — and our “hard” coating of HeatLock technology. HeatLock technology helps keep heat from escaping the home. When it’s combined with the right “soft” coatings, it can provide a glass option that’s suited to various climate types. Here are three options to be aware of:
Enhanced triple-pane glass options with HeatLock technology includes three Low-E coatings — two “soft” Low-E coatings applied on the inside of the IGU (see surfaces 2 and 4) and the “hard” Heatlock technology coating on the interior side (see surface 6).
Short answer: Yes, in the right location, in the right home, and for the right homeowner — triple-pane windows can be worth it. Here’s what we mean:
The exact cost will depend on the product line, type of window, and options added. However, it’s true that triple-pane windows typically cost more than standard dual-pane windows. Why?
Understand more about window and door costs or get specific details needed for budgeting by requesting a quote.
Triple-pane windows and code
If you live in a northern climate, you’ll likely begin to see more reasons to choose this type of glass — here's why:
Wondering which window and door products will meet ENERGY STAR criteria? Check out our guide to ENERGY STAR version 7.0.
