GSA-Tested: Solar Control Window Film Cuts Federal Building HVAC Costs by 29%
Mar 16th 2026
Source: U.S. General Services Administration, GPG-017: Solar-Control Films (January 2015). Produced in partnership with Lawrence Berkeley National Laboratory (LBNL). Public domain.
The Problem: Windows Are Responsible for 28% of Your Building's Cooling Bill
If you manage a commercial building, government facility, or institutional property, your windows are quietly draining your HVAC budget. According to the U.S. General Services Administration (GSA), heat gain through windows accounts for 28 percent of cooling energy demand in U.S. commercial buildings.[1] That is more than a quarter of your entire cooling load — delivered free of charge by the sun, every single day.
For a 135,000-square-foot federal office building, that translates to hundreds of thousands of dollars in annual energy costs that are preventable without replacing a single window.
The GSA's Green Proving Ground (GPG) program exists precisely to answer this question: which technologies actually work in real federal buildings, under real conditions, with real energy data? In 2012, the GSA commissioned Lawrence Berkeley National Laboratory (LBNL) to test solar control window film at the Goodfellow Federal Center in St. Louis, Missouri — and the results are directly applicable to any commercial building owner or facility manager in the United States.
What the GSA Actually Tested
The Goodfellow Federal Center is a three-story, 135,500-square-foot office building with double-pane bronze-tinted windows — the same type of glazing found in tens of thousands of commercial and government buildings across the country. LBNL installed a liquid-applied, spectrally-selective absorbing film on 25 windows across five different building zones and monitored energy performance for eight months.
The technology works by treating solar energy in the infrared spectrum — the portion of sunlight responsible for heat — while leaving visible light transmission largely unchanged. Unlike older reflective films that give windows a mirror-like appearance, spectrally-selective films are essentially invisible to the naked eye.
The performance data was striking. Using thermal imaging, researchers documented that untreated double-pane bronze windows registered an interior glass surface temperature of 91°F when the exterior temperature was the same. With the liquid-applied absorbing film installed, that same window registered 84°F under identical conditions — a 7-degree reduction in surface temperature that directly reduces radiant heat load on building occupants and HVAC systems.[1]
The Numbers: Up to 29% HVAC Savings
Because the mixed climate of St. Louis is not ideal for maximizing solar control film savings, LBNL expanded their analysis by modeling the energy performance of both absorbing and reflective films across a range of warmer climates.
| Film Type | Climate | Modeled HVAC Savings |
|---|---|---|
| Reflective (spectrally-selective) | Warm/Hot | Up to 29% |
| Absorbing (liquid-applied) | Mixed (St. Louis) | 8% cooling savings |
| Reflective | Single-pane clear | Maximum savings |
| Absorbing | Historic buildings | Recommended (no exterior reflection) |
"This is a glazing-dependent technology. When applied to single-pane windows, solar-control films, particularly the reflective variety, really do save energy." — Charlie Curcija, Principal Investigator, LBNL[1]
What This Means for Your Building
Cost-effective. With commercially available films carrying lifespans of 6 to 15 years, the payback period on a solar control film installation is typically 2 to 7 years depending on climate, glazing type, and local energy costs.
Non-invasive. Unlike window replacement, solar control film is applied to the interior surface of existing glass. There is no structural work, no permits in most jurisdictions, and no disruption to building operations.
Spectrally selective. Modern spectrally-selective films reduce solar heat gain (SHGC) without significantly reducing visible light transmission (VLT). The GSA-tested film reduced SHGC on single-pane clear glass from 0.82 to 0.45 — a reduction of 45 to 55 percent — while maintaining a clear appearance.[1]
Solar Gard: The Professional Standard for Commercial Window Film
The Window Place USA is an Authorized Saint-Gobain Solar Gard Distributor, supplying factory-sealed master rolls of professional-grade solar control window film to commercial contractors, government agencies, and institutional facilities nationwide.
Shop Solar Control Window Film →
SAM.gov registered. P-Card and agency quote orders accepted. Standard ground/freight shipping to all 50 states. Contact: inquiries@thewindowplaceusa.com | (866) 274-2769.
Frequently Asked Questions
Does solar control window film qualify for government procurement?
Yes. The Window Place USA is SAM.gov registered and accepts P-Card orders and agency quotes. All products ship standard ground/freight to all 50 states.
What is the difference between absorbing and reflective solar control film?
Absorbing films trap heat within the glass layer. Reflective (spectrally-selective) films reflect infrared energy before it enters the glass, resulting in greater energy savings in warm climates. The GSA recommends reflective films for most commercial applications and absorbing films for historic buildings.
How long does solar control window film last?
Commercially available solar control films carry manufacturer warranties of 6 to 15 years. Solar Gard professional-grade films carry industry-leading warranty coverage.
[1] U.S. General Services Administration. (January 2015). GPG-017: Solar-Control Films. Green Proving Ground Program. Retrieved from https://www.gsa.gov/system/files/GPG017-Solar%20Control%20Films-Findings-508R.pdf. U.S. Government work, public domain under 17 U.S.C. § 105.