A crossing is the space in a cruciform building (especially churches) where the nave (the longitudinal axis) and the transept (the cross arm) intersect. The crossing forms the central point of the building and is often crowned with a dome, tower or lantern. The four corner points of the crossing rest on massive piers or columns that support the enormous roof loads.
Characteristics of a crossing
| Characteristic | Description |
|---|---|
| Position | Intersection of nave and transept |
| Plan | Usually square |
| Crown | Dome, crossing tower or roof lantern |
| Supports | Four massive piers at the corner points |
Elements around the crossing
- Nave: the long central space of the church
- Transept: the cross arm that intersects the nave
- Chancel: the section beyond the crossing (towards the altar)
- Aisles: the lower spaces alongside the nave
- Crossing piers: the four columns that support the crossing
Crossing tower and dome
A distinctive element is often placed above the crossing:
- Crossing tower: a tower rising above the intersection
- Dome: a hemispherical covering above the crossing
- Roof lantern: a glazed structure admitting extra light
- Pendentives: triangular vault sections forming the transition from the square plan to the circular dome
Structural challenge
The crossing is the most structurally complex part of a church building:
- The four piers must carry the weight of the tower or dome
- Arches connect the piers and distribute the forces
- Vaults or domes span the open space
- Flying buttresses or buttress piers may provide additional stability
Related terms
- Transept: the cross arm of a church
- Nave: the main space of a church
- Chancel: the liturgical section beyond the crossing
- Aisle: the lower space alongside the nave
- Ribbed vault: vault with diagonal ribs above the crossing