Just to clear things up, in NSW strata a resolution of an owners corporation is a unanimous resolution if it is passed at a properly convened general meeting and no vote is cast against the resolution.
That’s significant as it doesn’t require everyone to vote in favour, which can often be hard to achieve for a variety of reasons.
All that said and done, Section 108 says this:
(1) Procedure for authorising changes to common property
An owners corporation or an owner of a lot in a strata scheme may add to the common property, alter the common property or erect a new structure on common property for the purpose of improving or enhancing the common property.
(2) Any such action may be taken by the owners corporation or owner only if a special resolution has first been passed by the owners corporation that specifically authorises the taking of the particular action proposed.