Over excavation
The term 'excavation' refers to the process of removing earth to form a cavity in the ground, typically to allow a below-ground structure to be constructed.
The term ‘over excavation’ refers to an excavation that goes beyond the depth required for the formation of a below-ground structure.
This might be necessary for example if the ground conditions at the level that the below-ground structure will be constructed do not have sufficient stability or load-bearing capacity to support that structure. In this case the excavation must be taken to a deeper, more stable level, the unsuitable material removed, the ground at the lower level may need to be treated to ensure it has suitable load-bearing capacity, then the excavation back-filled to the required level with suitable compacted fill.
[edit] Related articles on Designing Buildings Wiki
Featured articles
Check out some of the best features and news from Designing Buildings as well as key stories from around the web.
The heritage of nuclear and conventional power stations.
New measures to stop people being ripped off
Government to protect families from cowboy builders and aggressive bailiffs.
New Futurebuild showcase brings an innovation-first approach.
National Planning Policy Framework
Understanding the 2026 changes.
ECA's public affairs priorities
Member consultation opens to shape priorities for 2027 to 2030.
Dutyholder responsibilities from 1 July 2026.
Where performance meets practice
The Building Envelope Stage at UKCW Birmingham.
CIAT publishes briefing on planning reforms.
Leaders in Learning for Practice Network
Call for conservation leaders in learning to register interest in new network.
The importance of early engagement
Construction lessons from the Trillium HealthWorks Experience Centre.
Mayors are to be given planning call in powers
Mayors across England will be able to make the most important planning decisions.
The Master Builder: William Butterfield and his times. Book review.