Secondary windows—also known as interior storm windows, insulating panels, or secondary glazing systems—are a cost-effective, high-performance alternative to full window replacement for commercial buildings with old, inefficient windows. Secondary windows reduce heating and cooling energy use by up to 20 percent and cost 30 to 50 percent less than window replacement.
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High-Performance Windows at a Fraction of the Cost
Secondary windows—also known as low-e storm windows, insulating panels, or secondary glazing systems—are a cost-effective, high-performance alternative to full window replacement for commercial buildings with old, inefficient windows. Secondary windows simply attach to the interior or exterior of an existing (i.e., primary) window for quick installation, resulting in improved occupant comfort, health and wellness, while reducing heating and cooling energy use by up to 20 percent. Further, secondary windows can achieve about the same performance as replacing windows with new high-performance models, but for as little as half the cost.Resources
Commercial Secondary Windows: Ideal Buildings and Applications
Commercial secondary windows can solve a host of building energy and comfort issues, including thermal discomfort, exterior noise disruption, sun glare, draftiness, high utility bills, high peak load and HVAC system stress caused by extreme temperatures. However, studies show that secondary windows will provide the most benefit for existing buildings and windows with certain characteristics. Find out whether your building might be a good fit for secondary windows.Resources
Road Noise Disturbs the Peace at Portland Law Firm
When Portland law firm SBH Legal purchased their 1925 office building, they immediately noticed the road noise. While a full window replacement would be disruptive and cost-prohibitive for SBH Legal, they discovered a cost-effective, easy-to-install alternative called secondary windows.Case Studies
Secondary Windows Help Lead the Way to LEED Certification
In an effort to maintain the aesthetically pleasing and historically important appearance of the building’s façade, Montana State University turned to secondary windows to easily and more cost-effectively increase the building's energy efficiency and occupant comfort.Case Studies
Secondary Windows Bring Stellar Savings for Aerospace Firm
Crane Aerospace and Electronics is an aerospace components manufacturer in Lynnwood, Wash. After receiving thermal comfort complaints in the summer and winter from occupants of a second-story office building, Crane committed to replacing the inoperable single-pane windows throughout the building with energy-efficient secondary windows.Case Studies
Secondary Windows Rejuvenate 1970s Office Building
Built in 1975, Hurley Development’s 915 Broadway office building in downtown Vancouver, Wash., features floor-to-ceiling windows in every perimeter office—6,000 sq. ft. of windows in total. While all of these single-pane windows let in a vast amount of natural light, they also brought in far too much heat in summer, and too much cold air in winter. This thermal leakage not only led to tenant comfort complaints, it also inflated energy costs by forcing the aging HVAC equipment to strain to maintain indoor temperatures.Case Studies
A Window Solution That Meets LEED and Preservation Requirements
Built in 1909, Newcomer Hall at the Maryland School for the Blind in Baltimore, Md., is a private, nonprofit, state-supported institution attended by 73 percent of Maryland’s 1,800 blind or visually impaired students, age 3 to 20. The brick building provides space for early learning and elementary, middle, and high school programs. Due to its age, the building required a major restoration project that completely renovated the interior...Case Studies
Secondary Window Inserts Perform Flawlessly at Carnegie Hall
One of only four Carnegie Halls still in continuous use as a performance space, the Carnegie Hall in Lewisburg, W. Va., has hosted a wide variety of performers and artists since its opening in 1902. While the building's meticulous preservation has kept it as beautiful and impressive as it was more than a century ago, the building’s historic nature has led to increasingly higher energy bills every year...Case Studies
400 Market Street
400 Market Street is a 12-story, 200,000-square-foot office building owned by Kaiserman Company. The building, built in 1972, had already undergone several building energy performance upgrades, but its poor performing single-pane windows were a weak point. The property manager wanted to improve tenant comfort, reduce operating expenses, and improve the building’s ENERGY STAR® rating, while avoiding the costly and lengthy process of full window replacements.Case Studies
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