Glossary · C
Centring
Also called centering
The temporary timber framework on which an arch or vault is built and which is struck (removed) once the ring is closed.
See also: Voussoir
Rules that use the word
Every arch is first built on a frame. An arch cannot support itself until it is complete. Build it on a timber centring shaped to the intrados, strike the centring only when the keystone is set and the mortar has taken, and reuse it from bay to bay, which is one reason to keep the spans of an arcade equal.
Ribs first, webs after. Build the arches of the vault first (transverse, wall and diagonal ribs) on light centring, then fill the triangular cells between them with thin webs of stone laid course by course from rib to rib.
Where it appears in the book
In the chapters The Arch, Vaults, Domes, Byzantium and the Early Church.
A feature of Byzantine architecture.
Nearby in the glossary
Cavetto · Cavetto cornice · Cejiao · Cella · Chadar · Chaitya · Charbagh · Chattra