Outdoor showers are just about as common as indoor showers on Cape Cod, and they may come with a risk you were not aware of.

Fire crews in Harwich say they responded to a house fire in Harwichport on Saturday that was ignited by a mirror in the outdoor shower at the house.

The fire started in the rear of a ranch-style home at the corner of Sunset Lane and Victory Drive just before 2:00 p.m.

Investigators say there was “a significant fire condition” that had extended to the attic when fire crews first arrived.

“The cause of the fire is accidental, with the fire starting in the outdoor shower in the rear of the property,” according to a statement from the Harwich Fire Department. “It is believed the fire was caused by a mirror in the shower. This happens quite frequently in the spring.”

“During the springtime, the angle of the sun is lower, and shower mirrors, which are often concave, will magnify the sun’s reflection off the mirror and cause the exterior siding of the house, or the shower, to burn,” according to investigators in Harwich.

No one was home at the time of the fire and there were no reports of any injuries. Damage was estimated at $110,000 to both the property and the contents inside.

This is a developing story. Check back for updates as more information becomes available.

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