Around 70 firefighters were called to a blaze at a terraced property on Halesowen Road just after 4am.
A woman, a man and a boy suffering from smoke inhalation were treated at the scene and taken to hospital.
There are no reports of any other injuries, and the cause of the fire is under investigation.
Firefighters used a 32-metre turntable ladder as a water tower to extinguish the fire from above.
Crews also cooled one gas cylinder to an ambient temperature, as some cylinders can explode when exposed to heat.
It was removed and placed in a safe location.
