In 2010, conduction through windows in the commercial building sector accounted for 1.60 quads of lost energy used for space heating, but offset cooling loads by 0.3 quads. Additionally, solar heat gain through windows accounted for 1.38 quads of energy lost from space cooling, but offset heating loads by 0.97 quads. Recent advances in window technologies, for both reductions in conduction losses and solar gains, can help with tremendous energy savings in commercial buildings.

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Featured Solutions

Electrochromic (EC) windows can adjust their tint dynamically in response to environmental conditions. This ability of EC windows helps in the reduction in visual discomfort caused by glare from direct solar radiation. The case study report prepared by LBNL demonstrate the working of EC windows at the Donna Land Port of Entry.
The case study provides the performance of EnerLogic 35 window film which has a high solar heat rejection and superior low-e performance. This film can provide year-round performance without excessively reducing visible light transmittance.
This toolkit features webinars presented by the Better Buildings Alliance and Oak Ridge National Laboratory that focus on advancing the latest innovations for windows in commercial buildings.

Other Resources


This online calculator estimates the potential energy and cost savings from improvements in air tightness.

Case Study

This Sasha Bruce Youthwork home marks the first group home retrofit project to be featured by Building America. Retrofit measures included high efficiency air source heat pumps, duct sealing, building envelope air sealing, selective window replacement, increasing ceiling insulation, high efficacy lighting, lighting controls, and ENERGY STAR appliances.

Additional Information

Windows for High-Performance Commercial Buildings
Designing facades and selecting windows in commercial buildings is challenging because it is necessary to balance many often competing issues and criteria. This web site provides critical information and performance data on the energy efficiency, interior environment, and technical considerations that influence window design decisions.

National Fenestration Rating Council
The NFRC is an independent non-profit organization that establishes objective window, door, and skylight energy performance ratings to help you compare products and make informed purchase decisions

Attachments Energy Rating Council
The AERC is an independent, public interest, non-profit organization whose mission is to rate, label, and certify the energy performance of window attachments. 

Windows and daylighting tools
A list of tools and resources for windows from Lawrence Berkeley National Laboratory

Whole Building Design Guide
This Resource Page covers basic concepts for specifying window and glazing systems, particularly energy-efficient windows.

Window Coverings and Attachments
This overview covers all of the window attachment options and attributes, including a summary “Consumer Report-type” table.

Efficient Window Collaborative (EWC)
This site provides unbiased information on the benefits of energy-efficient windows, descriptions of how they work, and recommendations for their selection and use.

New Buildings Institute
NBI assesses technologies, promotes design approaches, and helps guide policies and programs that will significantly improve the energy efficiency of commercial buildings.

Green Proving Ground - GSA : Building Envelope
The Green Proving Ground program has commissioned Department of Energy National Laboratories to perform real-world measurement and verification of the following technologies in pilot installations in federally-owned buildings. 

American Society of Heating Refrigeration and Air-Conditioning Engineers (ASHRAE)
ASHRAE and its members focus on building systems, energy efficiency, indoor air quality, refrigeration and sustainability within the industry. 

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