Fires have caused damage to the two properties in Scullin and Ainslie this morning.
The first started in a dishwasher while it was running at a home on McIntosh Street just before 9.30am.
The fire was contained to the dishwasher but caused smoke damage to the rest of the three-bedroom home.
No one was inside at the time.
Crews were still ventilating the home at 10.30am, and the HAZMAT team were conducting atmospheric monitoring.
The second fire started in an exhaust fan at Ainslie Village on Quick Street.
Firefighters rushed to the scene and had extinguished the fire before 10.50am.
No injuries were reported from that fire, but ambulance officers were on scene.