It took 83 minutes to knock the fire down, according to the Los Angeles City Fire Department. Four units were damaged, and five others sustained collateral damage.
Two people were rescued from the third floor by firefighters using ladders.
Firefighters received a report of a fire at 5260 Bellingham Avenue in Valley Village at 10:03 a.m. Wednesday in a four-story apartment building.
A maintenance worker at the building heard a smoke alarm and found an active fire. He was able to safely exit the area and alert other people, according to the department.
Seven residents of the building were examined for smoke exposure. One woman was hospitalized.
The building was not installed with a sprinkler system.
The building was deemed untenable by the Los Angeles Department of Building and Safety.
As many as 75 residents were displaced. The American Red Cross opened a temporary shelter at the North Hollywood Senior Center.
The cause of the fire was under investigation.
The fire caused an estimated damage of $250,000.