The fire started around 11:15 a.m. at the Voyager Motor Inn on Sepulveda Boulevard. It took nearly 150 firefighters more than an hour to put out the flames.
When Los Angeles City Fire crews arrived on scene, flames were shooting through the second floor.
"They made a quick attack on this fire, and even still with a quick attack, there was just enough of a breeze, apparently, that helped this fire to spread throughout the building," said LAFD Battalion Chief Don Reyes.
Four people were treated for smoke inhalation. Residents say the second floor quickly filled with smoke. Hillary Blackstone, her two children and her fiance escaped unharmed, and their room was untouched by the fire.
"That was the most dramatic thing I have ever gone through," she said.
Residents who need temporary housing are getting help from the Red Cross. Meantime, investigators are still trying to determine how the fire started.