Firefighters have turned out to a second fire at a property in Waikiki in the space of just six months.
The blaze broke out in a tin shed at the back of the property on Burnside Way about 9.30pm on Sunday, October 4.
The neighbouring fence and shade cloth was also damaged in the fire.
It took crews about 40 minutes to control the blaze.
The cause is undetermined.
A WA Police spokesperson said they are treating the fire as a "mental health related incident".
The house was badly damaged by a fire back in March this year.
The cause of that blaze was non-suspcious.

The house suffered extensive damage in a fire back in March. PIC: 7NEWS
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