Triple Pane vs Suspended Film
The transition from single pane glass to dual pane (with a single chamber) provided an improvement in window energy performance. In much the same way, the introduction of multiple-chamber glass packages – with two to three insulating chambers and multiple surfaces using lightweight, suspended film layers – allow for significant improvements and advantages over triple-pane windows.
Triple-pane windows are often viewed as the best performing window on the market. This is a flawed concept; triple-pane windows do not automatically equate into the best thermal performance. Thermal performance of a window is dependent on the entire window system, not just the number of panes.
Problems with Triple-Pane Windows
Triple-pane glass units are signficantly heavier than Alpen Windows. The heavier glass units require stronger framing systems which can increase the overall cost of any building project. The extra weight can also impose strict size constraints, and may affect how much glass is used in the design of a building - impacting the overall aesthetics of a structure, as well as comfort, the amount of natural daylighting in a building, and even energy efficiency performance. General functionality of triple-pane windows is also affected by their weight. Additional stress is placed on all operable mechanisms of a triple-pane window as well as the window's hardware, wearing them out quicker.
Disadvantages of triple pane windows can include:
- Increased project costs (more labor, sturdier frames, stronger building design)
- Aesthetic and design limitations due to size constraints imposed on the glass and window units
- Extra weight caused by stress on the entire window frame, potentially creating gaps that will allow air, water and dust infiltration
- Amount of natural light in the overall design may be reduced
- Additional stress on operable portions of the window and window hardware
- Wider glass packages may not fit framing systems or window openings
Advantages of Suspended Film
Benefits of Suspended Film glazing in Alpen Windows:
- Suspended film (SF) is one of the most significant technologies critical to improving insulation and achieving higher performance across a broad spectrum of glazing characteristics - without any of the design and durability limitations typical of triple-pane glass systems.
- Internally mounted, suspended films work together to complement the benefits of low-e glass. Combining both film and glass-based coatings creates a lightweight, multi-chamber insulating glass unit that reflects heat and harmful UV radiation while maximizing light transmission, and provides superior insulating performance.
- One or more layers of suspended film in between two panes of glass are separated by low conductivity spacer systems to improve the insulating performance at the edge of the glass unit, providing high full-frame R-values. A variety of inert gases can also be used to fill the air spaces to further block heat transfer.
- Directional tuning to enhance daylighting while better controlling morning warmth and afternoon coolness
- 99.5+% UV protection reduces interior fading and damage and contributes to healthy, more comfortable indoors
- More architectural freedom to include more glass in the design than triple-pane windows
- Better condensation control with more insulating chambers than triple-pane windows
Triple Pane vs Suspended Film Comparison Chart
The chart below shows how triple-pane windows compare to Alpen Windows in several categories: Thermal performance, weight, winter glass temperature, UV blockage and more. Alpen Windows outperform triple-pane windows in every category.
|Window||R-Value||Avg. winter glass templ (F)||SHGC||Weight per ft.||UV blockage||Tuned solar control system
|AlpenWindows||Up to R-9.1||65||.20-.60||3.4||99%||Yes
|Triple Pane w/Low-E||Up to R-5||59||.27||5.1||94%||No
: the higher the number the better the insulating value
: the lower the number the more comfortable the window in the summer heat, while a high number can be used on certain elevations for passive winter-time heating.
: the higher the number the better the sound abatement.
Weight per ft
: important to keep weight low to minimize wear on operating hardware.
Tuned solar control
: the ability to provide windows/gas with different R-value, SHGC, and visible light characteristics to maximize comfort and energy efficiency.