Construction of the Baths at Caracalla: Basic Design
The decision to build a bath complex to serve several thousand people had a number of repercussions, since it was not possible simply to enlarge the plan of a smaller establishment.
Entrances and exits, and doors and passageways together form valves and controls; it is more practical to increase their number rather than their size. The Roman architect’s appreciation of this point is obvious from the design of theatres and amphitheatres. There was a need for more wall space to provide storage for the clients’ clothes rather than for more floor space in the changing rooms. The dry sweating rooms depended for their proper functioning on the radiant heat transmitted by the small conduit tubes lining the walls. Since the heating the conduits was helped by the rays of the afternoon sun the location of the conduits, the location of the primary heating source to the dry sweating rooms all had an impact on functionality. Another important factor was the maximum distance which a bather could be from a heated surface and still maintain the required elevated body temperature. Once again the solution lay in increasing the number rather than the size of the units. A similar argument can be applied to the heated pools of the caldarium; indeed, the caldaria pools in the imperial thermae are only half as large again as those in small Republican baths such as the Forum or Stabian Baths at Pompeii.
The decision to build a bath complex to serve several thousand people had a number of repercussions, since it was not possible simply to enlarge the plan of a smaller establishment.
