1. Trespass to individual private units
(i) Trespass by a co-owner
Because co-owners share the “unity of possession”, they theoretically hold an undivided share in the entirety of the land. Accordingly, as a matter of common law, one co-owner entering another’s unit does not automatically constitute the tort of trespass unless an “ouster” occurs.
For a trespass claim to succeed between co-owners at common law, the aggrieved party must prove that an “ouster” has occurred. Ouster involves one co-owner wrongfully and physically excluding the other from the possession and enjoyment of the premises. Examples include physically removing the other owner from the land, locking them out, or removing them by force. A mere unauthorised entry or temporary encroachment without total exclusion is generally insufficient to establish common law trespass.
However, the position at common law is substantially modified in the context of modern multi-storey buildings by the Deed of Mutual Covenant (DMC). A DMC is a multi‑party contract binding the developer, the first purchasers and, by virtue of assignment, subsequent owners of the flats, and it typically contains express covenants limiting how owners and occupiers may use both their private units and the common parts. The DMC governs the relationship between co-owners and provides for the management of the building, including the allocation of undivided shares and the granting of exclusive rights of occupation in respect of specified units. The DMC legally partitions the right of occupation, granting each co-owner the right to exclusive possession of their specific unit. Therefore, if a co-owner intrudes upon another’s unit in breach of the exclusive occupation covenant in the DMC, the aggrieved co-owner in possession may sue the intruding co-owner for breach of the DMC (infringement of the right to exclusive occupation granted in the DMC), even if the conduct does not meet the high threshold of common law ouster.
(ii) Trespass by a non-co-owner (third party)
Trespass by individuals who do not hold any ownership interest in the land (strangers, visitors, or property managers) is governed by the general law of trespass. Any direct entry onto another’s land without lawful justification constitutes trespass, regardless of whether damage is caused.
The Incorporated Owners or a building manager that enters or encroaches upon a private unit without authority is likewise a trespasser. There are, however, two recognised exceptions:
- Express DMC authorisation: Most DMCs expressly grant the Incorporated Owners or building manager the right to enter private units for specific purposes, such as inspecting structural safety, carrying out emergency repairs to common pipes, or remedying water ingress. Entry strictly within the scope of such authorised purposes is not a trespass.
Implied licence: A court will find that the consent of a private unit owner to allow access is implied when such access is reasonably necessary and incidental to the implementation of Incorporated Owners’ or building manager’s valid powers. For example, where a DMC permits cables or equipment to be installed on a common part of the building and the building manager is authorized to manage that part, it may impliedly authorise reasonable access over private areas where such access is necessary to carry out installation, inspection, maintenance, repair or removal.
