Firefighters were called to the property in Thomas Street, Thornton Lodge, shortly after 9.30am when it was reported that the group were trapped by smoke on the first floor.
A West Yorkshire Fire Service spokesman said: "The control room operator gave fire survival guidance to the occupants while appliances were en route.
"They managed to get onto a flat roof from where they were rescued by fire crews using a short extension ladder."
The crews from Huddersfield and Rastrick used four sets of breathing apparatus when they entered the property, which had no working smoke detectors fitted.
They found a small fire involving a microwave oven had created the smoke, which was cleared using a high power fan.
The spokesman said: "All nine people - a mixture of male and female adults and children - were transported to hospital suffering from smoke inhalation."