A to Z of Architectural Terms

...well A to T actually and there is no entry for the letter I but nevertheless here is a handful of interesting Architectural terms and their meanings!:

Atrium - (plural: atria) inner court of a Roman or C20 house; in a multi-storey building, a toplit covered court rising through all storeys.

Baluster - small moulded shaft, square or circular, in stone or wood, sometimes metal, supporting the coping of a parapet or the handrail of a staircase; a series of balusters supporting a handrail or coping.

Cornice - upper section of an entablature, a projecting shelf along the top of a wall often supported by brackets.

Dormer - a structural element of a building that protrudes from the plane of a sloping roof surface. Dormers are used, either in original construction or as later additions, to create usable space in the roof of a building by adding headroom and usually also by enabling addition of windows.

Estrade - French term for a raised platform or dais. In the Levant, the estrade of a divan is called a Sopha, from which comes our word 'sofa'.

Flying rib - an exposed structural beam over the uppermost part of a building which is not otherwise connected to the building at its highest point. A feature of H frame constructed concrete buildings and some modern skyscrappers.

Gambrel - a symmetrical two-sided roof with two slopes on each side

Hyphen - possibly from an older term "heifunon" - a structural section connecting the main portion of a building with its projecting "dependencies" or wings.

Jettying - a building technique used in medieval timber frame buildings in which an upper floor projects beyond the dimensions of the floor below.

Keystone - the architectural piece at the crown of a vault or arch and marks its apex, locking the other pieces into position.

Lunette - a half-moon shaped space, either masonry or void.

Molding - decorative finishing strip.

Niche - in classical architecture is an exedra or an apse that has been reduced in size, retaining the half-dome heading usual for an apse.

Oillets - arrow slits in the walls of medieval fortifications, but more strictly applied to the round hole or circle with which the openings terminate. The same term is applied to the small circles inserted in the tracery-head of the windows of the Decorated and Perpendicular periods, sometimes varied with trefoils and quatrefoils.

Pavilion (structure) - a free standing structure near the main building or an ending structure on building wings.

Quadriporticus - also known as a quadriportico - a four-sided portico. The closest modern parallel would be a colonnaded quadrangle.

Revolving Door - an entrance door for excluding drafts from an interior of a building. A revolving door typically consists of three or four doors that hang on a center shaft and rotate around a vertical axis within a round enclosure.

Spandrel - in a building fascade, esp. glass, the section covering floor partions.

Transom - window or element above a door but within its vertical frame.