The fire destroyed the third level of a triplex, where the missing man lived.
Fire crews were preparing to dismantle the heavily damaged building in search of the man.
Around 125 firefighters battled the fire that broke out around 10:15 a.m. ET Monday.
Residents interviewed at the scene reported hearing an explosion around the time the fire began and firefighters suspect the incident may be gas-related.
Firefighters worked to contain the fire and keep it from spreading to neighbouring buildings.
Another 43-year-old resident of the building suffered minor injuries in the fire.