K. Chalvatzi: Theatre Construction in France from 1780 to 1862

In France, construction of theatres rapidly evolved in the 18^th and early 19^th century in response to the growing demand for safe and convenient performance halls. Paris in particular, became a significant centre for theatrical activity during the 18^th century. Theatres became a field of experimentation with innovative roof designs and construction methods, in order to respond to the growing spans and loads of the roofs as well as the complex requirements of the machinery. At the same time, the extremely high risk of fire intensified the need for fireproof constructions.

The development of science and technology during that time facilitated the conception of innovative construction systems, including the application of iron in building structures. Iron was combined with ceramic tiles or pots for the construction of fireproof flooring. The idea expanded to iron roof trusses with vaulted fillings made of hollow pots, a system that was first applied on the roof of theatres in Paris at the end of the 18^th century. This construction method was revived in the beginning of the 19^th century, when numerous theatres were erected implementing it from 1827 until 1840.

This research traces the evolution of theatre roofs with a focus on the application of iron. Archival and published sources have been combined with on-site visits of historical theatres, in order to observe and document both timber and iron structures. This work covers a period from 1770 until 1862 and showcases timber theatre roofs from the late 18^th and early 19^th century and iron roofs from 1790 until 1862. The early implementation of iron is presented and contextualized through the selected examples. part from the recognized architectural value of historical theatres, this study aims to highlight their structural significance in construction history. Moreover, it creates a link between the structures and significant construction techniques, providing motivation for further study.