Common Property & the Lot

In a strata scheme you own or rent a lot. Effectively a lot is the cubic airspace (and anything included in that airspace) inside the boundary walls, floor and ceiling of your apartment or townhouse. Lot airspace may include balconies and courtyards. A lot includes the inner surface of boundary floors, walls & ceilings.

Everything that is not part of a lot is common property. It is owned collectively by all owners through the body called the owners corporation.

Common property includes:

  • the boundary walls of a lot
  • any windows and doors within boundary walls (including all their working parts)
  • the floor and ceiling of a lot
  • ceiling space
  • the roof

The above are general principles. Each strata plan can be different. The registered strata plan, specifically the floor plan, is the only document that legally defines the boundaries of the lots in a scheme. Copies of strata plans can be purchased from an information broker approved by NSW Land Registry Services.


Example floor plan in a strata plan

Example floor plan


In a typical floor plan:

  • Lot boundaries that are defined by a structural feature such as a wall are shown by thick lines. The wall itself is common property.
  • Only the perimeter walls of a unit are shown. All internal walls (ie walls between rooms in the unit) are part of the lot.

Making changes in the lot

Everything within the airspace must be maintained at the owner's cost. Tenants need permission from their landlords to make changes to a lot.

Making changes to common property

Changes to common property require a Special Resolution at a General Meeting of the owners corporation. (See How are decisions made in strata?)

This is relevant for sustainability initiatives such as:

  • Installing insulation in the ceiling space of a top-floor unit or a townhouse
  • Installing insulation in the wall space of boundary walls
  • Replacing windows and balcony doors with double or triple-glazed windows and doors
  • Installing solar panels or solar hot water
  • Installing a rainwater tank
Last Updated: 
Tue 09/02/2016

Share this page: