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definition strict definition

horizontal addition approved

A new addition at the side of an existing structure is approved by local authorities.

A horizontal addition to a built object is approved when formal permission is granted by local authorities (especially a municipal government) 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 approved extension must adjoin the existing object and rest on new foundations beside it. An addition supported on top of the object has the separate vertical-addition approval event.

Approval records formal permission, while proposal records the first announcement. Continuous physical work is recorded separately as horizontal addition begins construction.

Related definitions

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