Architecture Glossary

A - B - C - D - E - F - G - H - I - J - K - L - M - N - O - P - Q - R - S - T - U - V - W - X - Y - Z

J

Jalousie – a blind or shutter with slats which slope upwards from without to exclude rain and sun but admit air and some light; also an open-work grille covering a gallery in a church or a box in a theatre.

Jamb – The vertical face of an archway, doorway, or window; the part of the jamb which lies between the glass or door and the outer wall-surface is called a reveal.

Jamb shaft – A small shaft with capital and base placed against the jamb of a door or window, mainly in medieval architecture.

Jib door or gib door - A concealed door flush with the wall-surface painted or papered to correspond with the walls. The dado and other mouldings are similarly carried across the door.

Joggle, Joggling – Masons’ terms for joining two stones in such a way as to prevent them from slipping or sliding, by means of a notch in one and a corresponding projection in the other. It is often seen exposed on the face of a flat arch. If the joggle is concealed it is called a ‘secret joggle’.

Joist – Horizontal parallel timbers laid between the walls or the beams of a building to carry the floorboards. The undersides are either exposed to the room below and then often moulded, or have ceiling laths nailed to them for a plaster ceiling.

Jubé – The French name for rood screen.

Architecture Glossary

Home