A man who lives in the adjoining duplex unit said he was woken by glass smashing.
He ran outside got the garden hose on the fire but it soon became too much, and he had to back away.
He was not injured and was just pleased that his unit was largely unscathed.
The woman who lives in the unit was there yesterday but he didn't believe she was in it when it caught fire.
Several police were at the scene alongside firefighters. Given the fire erupted while no one was inside, detectives had also been called.
Other neighbours said they also heard the sound of smashing glass and were shocked to see the unit on fire.
