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Open Letter to Journalists
Over the course of the last few years, media have taken an increased interest in property damage caused by the concentrated solar reflection off multi-pane Low-e windows. Journalists initially focused their investigations on vinyl-clad homes; that fixed, large surface seemed at first to be the only material devastated by the strange phenomenon – but that’s neither the case nor “the story” any more. Numerous examples of damage to materials other than vinyl siding have now been documented.
The evidence is overwhelming and unavoidable that multi-pane Low-e windows are capable of concentrating and reflecting solar energy sufficient to damage a wide variety of materials. We strongly believe that it’s inappropriate for reporters to focus on the issue as if it affects only vinyl siding or, even more misleading, to report as if vinyl siding is exhibiting some defect. Instead, reporters need to explain how the characteristics of certain windows can combine to create conditions that greatly exceed the severity of natural outdoor exposure that many products are reasonably designed to withstand.
One fact is indisputable: the key factor common to every case of damage is the unnatural concentration of solar energy in the reflection off the concave, lens-like surface that can occur in window glass under some conditions.
Below are various examples of property damage that have been documented by journalists over the course of the last 10 months. In every case, the devastation is caused by the concentrated reflection of solar energy from multi-pane, Low-e windows:
- A resident in Los Angeles and another in Hyde Park, MA show off melted car parts;
- An Arizona resident releases video footage of the “problematic X” burning his sofa;
- A subscriber writes in to Fine Homebuilding that his laptop keyboard was melted by “sunlight bouncing off multi-pane Low-e windows on a house 20 feet across the street,” during the winter; and
- The car manufacturer Toyota released a statement to CBS San Francisco that read, in part: “Concentrated solar reflection was causing damage to the spoiler of our customer’s Toyota Prius.”
We know, and the window industry knows, and your viewers or readers should know, that the solution lies in finding a way for windows to reflect solar energy without concentrating it into a dangerous beam.
We’re always available to go on background or on the record to ensure that you have all of the information you need to set the record straight.