As if inattentive drivers, potholes, vandalism and acid rain weren’t enough to worry about, it now seems that urban motorists have one more thing to raise their insurance rates.

As one southern California resident recently found out, high-thermal-efficiency windows can reflect a significant amount of heat back into the environment.

Enough heat, in fact, to melt plastic, like that used in the side-view mirror covers of a Toyota Prius.

As CBS Los Angeles reports, Heather Patron originally attributed her melted Prius mirrors to a design defect, and went to Toyota for repairs under warranty.

Toyota shrugged it off, saying that the damage was caused by an external source, not a design or manufacturing problem. Ultimately, Patron paid to replace the mirror housings out of her own pocket.

While parking under her carport shortly after, she noticed the mirrors on a neighbor’s car were also melted.

The culprit was an energy-efficient window in a neighboring condominium, which focused a concentrated beam of sunlight into the parking spaces of Patron and her neighbor.

On an overcast winter’s day, a reporter was able to obtain a temperature reading of 120 degrees Fahrenheit from the light beam, meaning that a stronger summer sun would likely produce the kind of temperatures needed to melt plastic with prolonged exposure.

So where does that put Patron? Out of luck, apparently. The condo where the window is installed is vacant, and attempts to track down the owner have proven unsuccessful.

Local building officials are indifferent, pointing out that energy-efficient windows don’t violate any established building codes.

Patron’s case apparently isn’t the first one, either. In fact, the problem is widespread enough that the National Association of Home Builders is looking into it.

If you find yourself in a similar situation, we’d suggest trying a good car cover first.

If that fails, moving to the country is always an option.


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