Vault (architecture)

Architectural term for an arched roof

In architecture, a vault (French voûte, from Italian volta) is a self-supporting arched form, commonly of stone or brick, serving to cover a space with a ceiling or roof. As in building an arch, a temporary support is needed while rings of voussoirs are constructed and the rings placed in position. Until the topmost voussoir, the keystone, is positioned, the vault is not self-supporting.

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