The fire at the 20 room outdoor retreat on Forest road is just across the City boundary line between Stratford and Perth East.
The main building at the facility looks to be a loss as all that remains is smoking charred structure.
The fire was still active into the late morning and extended further into the back of the building.
The weather made fighting the fire more difficult to fight. Forest Road and the nearby railway tracks have been closed to traffic due to their close location to the fire.