11 people have been rescued from a fire on Mountjoy Square North and over 150 people were evacuated from over 30 apartments in the building.
The alarm was raised at around 7.20am this morning.
Dublin Fire Brigade say eight pumps, two ambulances, a ladder and an aerial team attended the scene and crews searched the premises.
Brendan Carroll from Dublin Fire Brigade described the scene when they got there: "The fire started in the basement, I don't know how, under the staircase and travelled up throught the staircase and made a chimney out of it. The fire made the staircase unusable. We rescued 5 off the top window off the ladder, we rescued 3 off another window and we took 3 out the back."
Five people were taken to the Mater as a precautionary measure.