Crews from five departments responded to the blaze at 10920 199th Avenue Court East at about 11:25 p.m. Thursday after receiving 911 calls from witnesses who drove by and saw smoke coming from the building.
Witness Logan Cutts told KOMO News the fire started small then seemed to grow suddenly.
"It started off as just smoke, then increasingly it got bigger and bigger until it was flames shooting out of the side further and further up the building," he said.
Firefighters were able to keep the flames from spreading beyond the building's attic.
There were no injuries. The cause of the fire is under investigation.