The blaze broke out just before 6:30 a.m. at 65 Adams St. near the intersection with Orchard Hill Drive, authorities said. The fire started in the living room and quickly spread.
Westborough firefighters were fast to the scene, and with help from several area fire crews, they had it under control by 7:15 a.m., officials said. Grafton, Hopkinton, Northborough, Shrewsbury, and Southborough departments assisted.
The fire marshal estimates the home received about $500,000 in damages.
Firefighters closed Adams Street near Orchard Hill Drive for several hours as they cleaned up the scene.
Officials didn't say what caused the blaze, but Westborough Fire Department Chief Patrick Purcell asked residents to be careful when using space heaters or external power cords, especially with more cold weather on the way.
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