What's the difference between my condo unit and the common elements?

In an Ontario condominium, your "unit" is the space you own exclusively — typically defined in the declaration and measured from certain boundary surfaces such as the undecorated surfaces of walls, ceilings, and floors. Everything outside those boundaries, including the building structure, mechanical systems, corridors, lobby, roof, and parking garage, generally forms the common elements owned by the condominium corporation.

The exact boundary depends on the specific declaration registered for your building. Some declarations include the drywall, flooring, or plumbing within your unit; others stop at the structural concrete. Getting the boundary wrong can cause expensive disputes about who pays for repairs.

Limited common elements are common elements designated for the exclusive use of one or more units — for example, a private balcony or a parking space. You have exclusive access but the corporation typically maintains them unless the declaration assigns that obligation to the unit owner.