Roman central heating

• The Hypocaust was the Roman central heating system used in the Roman Baths and in the Roman Villas.
• A good example of a Roman Hypocaust lies under a mosaic in the Park at St. Albans, next to the St. Albans Museum.

Heating the Roman Villa

• The Hypocaust:
  • The floors of the Roman Villas were raised on pillars.
• The Walls:
  • Hot air rose up through pottery pipes placed against the walls.
• The Praefurnium:
  • Hot air was supplied from a wood burning Furnace called the Praefurnium.
  • Hot air from the Praefurnium was then allowed to circulate underneath the floors

Heating the Roman Baths

• The Hypocaust:
  • The floors were raised on pillars, to allow the hot air to circulate underneath them.
• The Walls:
  • These had hollow flues through which hot air rose up from below.
• The Praefurnium or Furnace:
  • This was kept burning by Slaves. The Calderium was above the Furnace making it the hottest room.
  • Hot air then circulated under the Hypocausts and up the walls of the Tepidarium, and then the Frigidarium, which was the coolest room because it was the farthest away.