Cobra – yes you are correct, the front door and any locks /locksets that were installed at the time of your Units construction are Common Property, and the maintenance and replacement of those is the responsibility of your Owners Corporation (O/C).

Your ability (as an Owner) to change that lock / lockset or to install additional ones depends upon the applicable By-Law in place at your Plan.

Before doing anything you need to check the wording of that By-Law, but it’s likely to be (in NSW) the Standard By-Law #5 where the changes that you propose may be undertaken in specific circumstances without the prior consent of your O/C, including for the “protection of the owner’s lot against intruders or to improve safety within the owner’s lot“.

Regarding the numbers of locks that may be installed, you can only use your common sense, and remember that if you ever decide to sell or rent your Unit potential purchasers / tenants that see multiple locks will wonder about the security of the Plan and about the neighbours, and think twice.

As for the style, and type of locks / locksets that may be installed, you’ll need to match any new lockset with those in place elsewhere in your Plan (e.g. don’t use gold coloured fittings if those existing are brushed aluminium), if the entry door is “rated” you need to ensure that fire safety is not compromised, and given you’ll be responsible for the maintenance / repair of whatever it is that you have professionally installed remember – cheap locks aren’t good and good locks aren’t cheap.

Possibly yes, it depends upon to what standard an entry door is fire-rated under the Pt 9 requirements proposed by the Developer and approved by the Local Council prior to the commencement of the Building’s construction.

Modifications to entry doors such as the deadlocks you mention (some are OK), together with security chains, spy holes or the removal of door closers can indeed compromise an entry door’s fire rating, and that’s why I suggested that Cobra first checks the wording of the relevant By-Law that’s in place at his/her Plan.

The Standard By-Law 5 (in NSW) that I referred to in my last post states that an Owner may NOT fit any additional device to an entry door if “the device is likely to affect the operation of fire safety devices in the lot or to reduce the level of safety in the lots or common property“, and yes you’re right again – some Plan-specific By-Laws include a requirement that any modifications to a fire-rated door that compromise or breach the Building’s Pt 9 Standards (e.g. a “fail”) will need to be “un-modified” and returned to a compliant state at the expense of the “modifier”.

I reiterate to Cobra, read your Plan’s relevant By-Law first!