I would strongly advise any Owners Corp confronted by partitioning of rooms to take advantage of Section 137 (below) of the NSW strata Act and, as soon as possible, pass a by-law limiting the occupancy of any of the lots to no more than two adults per bedroom.
Note that Section 137 (6) defines a bedroom as “a room approved for use as a bedroom under, or indicated as a bedroom in any plans the subject of, a planning approval …”
I would also note that the fines for exceeding those limits are punitive – $5,500 for a first offence and $11,000 for subsequent breaches – all payable back to the Owners Corporation.
The answer for the owner who wants to add the bedroom to seek planning approval for the additional room … and I’d lay odds that they won’t get it, for very good reason.
137 Occupancy limits
(1) A by-law may limit the number of adults who may reside in a lot by reference to the number of bedrooms of the residence.
(2) The limit may not be fewer than 2 adults per bedroom.
(3) The by-law has no effect:
(a) to the extent to which it is inconsistent with any planning approval or other law applicable to the lot, or
(b) in any other circumstances prescribed by the regulations for the purposes of this section.
(4) To avoid doubt, the Tribunal may make an order under Division 5 about a by-law made under this section.
(5) The regulations may provide for the circumstances when a person is a resident of a lot for the purposes of a by-law made under this section.
(6) For the purposes of this section, a bedroom is a room approved for use as a bedroom under, or indicated as a bedroom in any plans the subject of, a planning approval and includes any other room prescribed by the regulations as a bedroom for the purposes of this section.