Qualifications

Hey, i am a tiler and a bathroom renovator in Melbourne. I am a qualified tiler and licensed waterproofer. Occasionally i come into contact with a rotten joist of bearer. Mostly Joists. Do i need to employ a qualified carpenter with structural framing experience to replace it? Also if i find a single stump that is affected by water damage can i repair that also. As long as i am building to australian standards. Isn't it ok if i do the works if it is under a certain dollar figure?
Cheers
Rob