Sudatorium
The sudatorium (plural: suadotria) was the steam room of the Roman bathing complex. The name is derived from the Latin word for steam, sudationes. Not all bathing complexes had a sudatorium, as it was not one of the three primary bathing chambers. This room was similar to the laconicum in that it was often (though not always) circular in shape with a domed ceiling. It was heated through an underfloor hypocaust system that allowed heated air to be circulated underneath the floor of the laconicum after being heated in the praefurnia, the bath furnaces. It was also typically supplemented by the hollow tubuli wall tiles that allowed the heated air to travel up into the walls, heating those in addition to the floor. The sudatorium differs from the laconicum in that the laconicum was a dry sauna with high heat and low humidity while water is added to the sudatorium, making it both a high heat and high humidity steam bath.
