The team at Kerin Benson Lawyers has written this handy fact sheet which summarises what you need to know before you start work to improve your strata lot.
The general rule is that if you are altering the common property in any way, you will need to get a by-law passed before doing the work. The fact sheet explains how to go about obtaining such a by-law, what information is required and what to do if the owners corporation refuses to pass your proposed by-law.