Anatomy of a Window: Basics for High-Performance Windows

It’s time to get up close and personal with windows! We usually just focus on the scene we can see through the window, but what looks so simple can actually be very complex. 

There are three main sections to the overall anatomy of a window: frames, spacers, and glass. While we often focus on the shiny, pristine look of the clear glass, we understand that ALL parts of the window are vital for overall performance and ultimately providing better thermal performance for any house. 

Window Frames:

We often focus on the glass performance, but the frames are quite literally what holds so much integrity for the window performance. Not only do they offer structural support, but they are huge opportunities to preserve energy efficiency. Most companies don’t insulate the frames, but high-performance manufacturers will use various types of insulation. These can vary from EPS, wood fiber, and Polyurethane. 

At AE Building Systems, we’re big fans of:

  • Tyrol, Tyrol PH+ Windows, with either EPS or Graphite for insulating support
  • Zenith Windows (with Polyurethane), which offers higher insulation value per inch 
  • Smartwin by Advantage offers wood fiber and XPS insulation options
  • Advantage Mira, not insulated much, as it’s made of mainly wood (R-1 per inch)

Window Spacers:

Spacers are a vital part of every window’s anatomy and help provide structural integrity of the glazing unit while promoting a thermal and moisture seal. Spacers are usually made with either aluminum, steel, stainless steel, warm-edge, or composite. When a high-quality spacer is used along with gas filling and low-e-coated glass, the overall energy-efficiency of the window is improved.

Window Glass: 

Simplicity is the ultimate sophistication. – Leonardo Da Vinci

While it may look like just a simple, clear pane you look through, what’s going on is actually pretty sophisticated. There are so many factors to think of when it comes to insulated glass. Insulated glass is insulated with gas, such as Argon or Krypton, and the cost for these gasses varies based on the current market price. Elevation also plays a factor in expansion levels for gas, and with our team based in Colorado, we are highly aware of ensuring that windows are manufactured appropriately based on the elevation they will be used at. To quote our friend Leonardo, insulated glass is highly sophisticated, but can appear so simple to the untrained eye! 

Below are some of the most common options for residential window glass:

Double-Pane Windows:

A double-pane window has two panes of glass set into each window frame. The two glass panes have a small space between them, which creates an air pocket to provide a small level of insulation. If you’ve ever felt a single-pane window on an antique window or in an older home, you know that there’s minimal insulation and the glass is going to be very cold or very hot depending on the season. However, many homes historically have leaned toward double-pane windows, which will still be warm or cool to the touch, but not as drastic. While more cost-effective upfront, double-pane windows can cost you more in the long run as they aren’t nearly as efficient for insulation and energy transfer as other options available today. 

Euro Triple-Pane Windows: 

European windows are well known for their high energy efficiency. Their design allows less heat to pass through from your house when it is cold outside. Triple-pane windows are better thermally because of the added pocket depth for argon gas between the window panes. They ultimately have the potential to reduce energy costs, reduce noise, increase comfort, and even reduce the size and wear on HVAC equipment.  

Quad-Pane Windows: 

Quadruple Pane Windows, or Quad Glazed Windows, include four high-performance layers of glass with three gas-filled sealed air spaces in between. With an added pane of glass, they are a solid solution in terms of insulation, heat transfer, and other aspects as well. Think of all the benefits of double-pane and triple-pane windows but with an additional pane. Of course, any time you add material, you add weight, cost, and complexity. For many residential situations, triple-pane ends up being the nice winner for an all-around solution that supports energy-efficiency, more common construction practices, and construction budgets. 

Thin Glass vs. Thin Film Windows

Thin Glass and Thin Film are like cousins, who are similar, but just not completely the same product. They also are very similar to triple-pane windows in a high-level concept. Thin Film has been Alpen’s go-to for many, many years, and will still be available for many of their lines, such as Zenith and Tyrol. However, Alpen recently released Thin Glass, which acts like a triple-pane window at a double-pane’s weight. Of course, it’s much more complex than that. You can read up on more of the details to these innovative options here, where we break down how they’re similar and how they differ.  

Innie vs. Outie Window Construction

In construction, this great debate has been going on for some years and it can be confusing to know what the right solution is for your project. Each style has been used in various ways over the years, but if you’re like us and are concerned about thermal performance and energy savings, you will want to read our detailed blog

Windows are one of the most important features in a home, especially if you love where you live (like we do here in Colorado)! You want to let the local scenery and the sunshine in, but you also don’t want to sacrifice thermal efficiency. That’s why it’s so important to get the window purchase right when you’re building or upgrading a home. Some window options will be better for you than others and that’s where our team is here to help! Let us help you find the best high-performance window to meet your needs. We’re here to answer any and all questions; email 

Leave a Reply

Your email address will not be published. Required fields are marked *