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definition strict definition

horizontal addition proposed

Plans for a significant side extension adjoining an existing object and resting on new foundations are first announced.

A horizontal addition to a built object is proposed at the first announcement of plans for construction of a significant extension at the side of the existing object, abutting it while resting on new foundations. If the addition is built on top of the existing object, it should be classified as a vertical addition.

The proposed extension must abut the existing object while resting on new foundations beside it. A detached object nearby does not meet the horizontal-addition condition.

The event records the first announcement. Approval and the start of construction are separate milestones and are not established merely by proposing the addition.

Related definitions

Definition
strict definition
Key
timeline.horizontal-addition-proposed
Last updated
Sep 10, 2026