Cylindrical roof.

the simplest form of vault; a single continuous arch

continous vault of semicircular cross-section; also called tunnel vault

A roof of hemi-cylindrical shape. In Egypt, used for lids of Old Kingdom sarcophagi.

A vaulted ceiling of semi-circular shape, creating a dome-like appearance.

A tunnel like hall (i.e. vault) created by building a long series of arches.

Barrel Vault is one way of describing a brick bread oven. This oven style has also been called a Letterbox Oven, because the shape resembles a rural letter box. The footprint of the oven is rectangular, and the dome is a curved vault, or barrel vault that looks much like a Gothic Cathedral. You see this oven style in traditional French and Scottish bread ovens (which are large commercial ovens) and in the brick oven plans desribed in other books and web sites. While this style oven works well for large-scale bread ovens, it is a poor choice for either home brick oven owners or pizzerias. The thermal mass of the oven result in long oven heat up cycles and poor fuel economy and the shape is not suited for fire-in-the-oven cooking and pizza.

Also called tunnel vault, it is the simplest form of a vault, consisting of a continuous surface of semicircular or pointed sections and has the form of a tunnel.

A masonry vault in the form of a semicircular arch.

a form of ceiling or roof in which masonry is laid to form a continuous semi-circular arch (ATA fig. 7-4a; 12-5)

A Barrel vault, also known as a tunnel vault or a wagon vault, is an architectural element formed by the extrusion of a single curve (or pair of curves, in the case of a pointed barrel vault) along a given distance. The curves are typically circular in shape, lending a semi-cylindrical appearance to the total design. The barrel vault is the simplest form of a vault: effectively a series of arches placed side by side, i.e., one after another.