A constricted spire is a tower spire that suddenly becomes narrower (constricts) at a certain height, in order to widen again above that point or continue in a slimmer form. The “constriction” is a waist in the spire, so that the silhouette does not follow a single straight line but takes on a pinched, articulated profile.
Form and characteristics
With an ordinary needle spire the roof tapers up in a single straight line. With a constricted spire that line is interrupted:
- The lower part tapers upward and narrows sharply (the constriction)
- Above it the spire widens again or continues into a second, slimmer top
- A cornice, balustrade or gallery often marks the point of the constriction
This form gives the tower a graceful, dynamic silhouette and is found mainly on church towers and monumental buildings.
Application
- Church and town-hall towers — as a characteristic landmark in the silhouette of a town
- Historic architecture — the form is related to other articulated spires such as the pear or onion-shaped spire
- Restoration — when repairing monumental towers the original constriction is accurately reinstated
Points to note
- The constriction requires a carefully worked-out roof structure, because the cross section changes over the height
- The transitions are vulnerable to water and require good lead flashing and detailing
Related terms
- Spire
- Roof truss
- Roof structure
- Ridge
- Lead
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