A hypocaust is a Roman heating system with a raised floor beneath which warm air and smoke flow. The floor rests on short pillars, the pilae, usually made of stacked bricks or tiles, so that a hollow space forms underneath the floor.
How it works
Warm air and smoke from a furnace, the praefurnium, flow through this hollow space under the floor. Sometimes the heat also rises through hollow wall tiles, the tubuli, along the walls. In this way both the floor and the walls are heated.
- The floor stands on pilae, creating a hollow space.
- Warm air and smoke come from the praefurnium.
- Tubuli carry the heat upward along the walls.
Application
- Roman bathhouses (thermae)
- Wealthy villas
The hypocaust is one of the earliest forms of central heating and underfloor heating. Its principle — releasing heat evenly across a large floor surface — resembles modern underfloor heating.
Related terms
- Convection
- Brick
- Domus
- Low-temperature heating
- Floor
- Radiation
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