Reflection from low-energy windows creates enough heat to melt siding

WILMINGTON, N.C. (WECT) - They’re called energy efficient windows, and they’re designed to help you save money.

They could end up costing your neighbors in repair bills.

Reflected sunlight coming off some of these windows has melted siding on other homes.

John Norwood, owner of window tinting company Carolina Solar Security, knows firsthand. He has fixed several problems in the Cape Fear region.

Norwood said the low-energy (low-e) windows’ metal coating is thin as a human hair, and can create an even more intense reflection of sunlight off the window onto a nearby home.

“Low-e was designed basically for more northern homes to hold the heat inside the house during the winter, but it came down here and it’s almost like it just reflects so much of that energy off the glass that it can burn you if you stand there long enough," Norwood said. “It reaches up to 200 degrees.”

According to Norwood, siding starts to melt at 165 degrees. South and west facing windows that reflect sunlight on another home can start warping pretty fast, he said.

The reflective heat can also burn grass, and show up in the shape of the window on the ground.

“There was one incident in Southport where the gentleman had a big round window at the top of his house," Norwood said. "He had a beautiful yard, except for a very large round circle of dead grass right in the middle of it.”

Norwood said warped siding happens more often when homes are built close together. His company puts a film on the outside of the glass that doesn’t reflect out as much heat to help fix the issue.

When he first saw it happen, Norwood admits he was stumped.

“We couldn’t figure it out," Norwood said. “When people called us and said ‘What do you have that you can put on my windows to stop this reflective heat from melting my neighbor’s siding?’ and we said we’d never heard of such a thing. We went out and saw it and it was phenomenal.”

The company has received more calls in the past month due to the record-breaking heat, Norwood said.

“It’s an act of nature. It’s the consequence of trying to keep everybody energy efficient,” he said.

Norwood’s advice is to have builders check the windows before they’re installed to sandwich the coating in between the two window panes to try to prevent the problem.

If the warping already happened, homeowners can put an exterior coating on the window, or put mesh screens on the outside of the window to reduce the reflective heat.

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