Thermal Sustainability: Renovation of Imperial Thermae in Late Antiquity

Abstract

Architectural sustainability was a time-honoured practice in the ancient world, seen through evidence of cyclical repair, renovation, and restoration of essential infrastructure. In so doing, the resilience of monuments\xa0and by extension, of cities themselves, was guaranteed into the long term. Thermae, or baths of extraordinary size, were erected during the Roman Empire’s ambitious Imperial period. In the wake of the social and economic upheavals of the 3rd century, however, most of them became redundant by the 4th. But against the odds, a select group of Imperial-period baths continued to provide bathing facilities to the public throughout this turbulent period. Archaeological evidence reveals their transformation into ‘summer baths’, of which a few survive. Through their sustainability — a phenomenon\xa0confirmed by evidence of substantial repair — a narrative of resilience may be recorded. This article relies on the surviving archaeological material of these ruins — in particular, their campaigns\xa0of renovation — to argue not only for a rationale of sustainability in the ancient world, but also to introduce the concept of architectural resilience as a practice as old as the profession of building itself. While spoliated inscriptions and contemporary authors identify 17 summer baths in the Late Roman world, the five surviving structures in Sbeitla (Tunisia), Thuburbo Majus (Tunisia), Madaurus (Algeria), Fordongianus\xa0(Sardinia), and Aphrodisias (Turkey) bear witness to an understanding of thermal sustainability in Late Antiquity that prioritized conservation of heating and water resources, attuned bathers’ activity to climate, and maintained these civic centres as sites of cultural and aesthetic value.