maximum height reached
The highest element included in a structure's architectural height is fixed in its designed position.
The maximum height of a structure is reached when the highest element included in its architectural height is affixed in its designed place. This is often called the topping-out of a structure, but is not exactly the same as the event which changes a structure's status to topped out - namely the completion of its framework. The maximum height can be reached before or after the whole framework is completed, and this event does not change the status of a structure.
The reference is architectural height. A tower crane can extend higher during construction without establishing the structure's maximum architectural height.
Framework completion requires every load-bearing member to be installed. Reaching the highest architectural point can occur while other members are still missing, or later when a non-load-bearing top element is added.