Windows are a crucial, though sometimes underrated, part of a facility’s energy efficiency strategy. Windows also dramatically affect occupant health, wellness, and safety. Because windows are often a big investment, and aren’t changed frequently, it’s very important that critical criteria are evaluated during the window selection process.
As energy codes evolve more and more, the introduction of the triple-glazed curtain wall has provided a solution that allows buildings to have better thermal performance as today’s buildings are required to become more efficient, says Tim Bailey, partner and associate principal at Margulies Perruzzi Architects.
“Curtain wall manufacturers are also looking into the details, specifically how to control thermal breaks in the design of the curtain wall system,” Bailey says. Electrified glass panels (dynamic/smart glass) have also evolved over the last decade with manufacturers integrating coatings that can change the visible light transmission (VLT) and reflectivity of the glass based on the environment around the building.
Deborah Callahan, CEO, National Fenestration Ratings Council (NFRC), says that there have been some significant advancements in window technologies in the last decade, but many are improvements by manufacturers while the more sophisticated are still in the development process.
“The proprietary advancements can include adaptations to glass and glass coatings, gas fills, improvements in frame construction and insulation, and more,” Callahan says. “These changes, while providing improvements in performance, are not typically visible to the purchaser of the window other than through labeling.”
As such, Callahan says the more significant advances in technology include developments such as vacuum insulating glazing (VIG), dynamic glass, silica aerogel layer, photovoltaic glass, and thin glass.
“These technologies are in varying stages of development; VIG, dynamic glass, and thin glass are the technologies already available to be NFRC certified,” Callahan says. “The remaining technologies are being tested for viability, durability, etc., at national labs. Additional testing to ensure that NFRC’s current test methods will provide accurate results will also need to be completed prior to approval as NFRC certified products.”
Maura Keller is a freelance writer based in Plymouth, Minnesota.
