User:Amaaaai/New sandbox

Opus reticulatum
Concrete facing
Features	Net like pattern
Surface	Tufa, rubble mortar

Opus reticulatum (also known as reticulate work) is a facing used for concrete walls used in Roman architecture from about the first century BCE to the early first century CE.[1] They were built using small pyramid shaped tufa, volcanic stone which were embedded into a concrete core.[2] Opus reticulatum was generally used only in Italy with possibly the exception of Africa because of tufa’s wider availability in the region and ease of local transport.[3] Within Italy there are some regional differences as Rome usually covered the facing with a veneer but rarely anywhere else.[4]

Reticulate work developed from opus incertum, an earlier form of facing to accommodate with growing urbanisation of the Roman population by making the technique more uniform and accessible to unskilled labourers.[5] This need for quicker and easier techniques lead to a decline in popularity with brickwork being a convenient alternative especially after the Great Fire of 64 CE.[6]

Opus reticulatum is essential in understanding the architectural restraints and developments Rome made during their time.[7] As the rise of urbanism in the Late Republic brought about the need to accommodate for such changes. Further, the technique is also important for dating of buildings in modern scholarship where there is an absence in explicit evidence to date the construction.[8]

Construction and Use

Opus reticulatum was constructed using small pyramid shaped tufa embedded into the core of opus caementicium forming a net like pattern.[1] The uniform shape of the stones made it easy to assemble which allowed Rome to delegate the work to unpaid labour with little training to construct architecture using the facing.[2] The technique was typically used for a variety of constructions including walls, aqueducts and other works which relied on rubble mortar.[3]

Reticulate work was able to be stylised and could incorporate different types of materials including limestone, lava, bricks, and other varieties of tufa to produce a polychrome colouring.[4] Opus reticulatum could also be used interchangeably with a variety of other facings to form opus mixtum throughout its usage in the Republic and the Empire.[5] Such customisation could also produce lines, complex figures, and letters but they were covered with a veneer, possibly a later addition or a request from the commissioner.[6] During the late Augustan period, opus reticulatum in Rome was hidden by a veneer.[7]

Location

The architectural technique was typically found in central and southern Italy with rare appearances in Africa.[1] This is because tufa is predominant in Italy compared to other Roman provinces due to their volcanic environs they inhabit.[2] Further, stone was difficult to transport long distances and had to be partially cut to decrease weight before being sent to the site of construction.[3] This was not the case for tufa which could be easily transported and used in central Italy and Campania which became a common building stone.[4] Rome also did not typically change the core building materials used in the areas they conquered but adapted to them and used what was readily available to them.[5]

Development

Rise

Opus reticulatum was preceded by opus incertum, a facing using uneven shaped tufa which mostly disappeared by the late first century to accommodate for the growing architectural needs after the Social War and Civil War.[1] Such pressures lead to the development of opus quasi-reticulatum, an architectural technique like opus reticulatum but more irregular in shape. The former went out of style with the advent of reticulate work which employed more uniform shaped tufa.[2]

Popularity

Opus reticulatum was created as a response to the growing demands of urbanisation, its pyramid shape was easy to assemble and required little training for unpaid labour to complete compared to the more uneven opus incertum.[1] It became the more popular facing from 100 BCE onwards remaining as such by Vitruvius time until the early Empire during the second century CE.[2] Craftsmen during the Augustan period refined their skills using opus reticulatum incorporating polychromatic colouring into their work to enhance the aesthetic appearance of facing.[3] They also combined the technique with other facings to produce opus mixtum which co-existed with reticulate work until the arrival of opus testaeceum.[4]

Decline

The popularity of reticulate work eventually waned during the early imperial period before dying out entirely during the Hadrianic and Antonine period in the second century CE.[1] This was because of the technique’s weaknesses and the increased pressures from Rome to further streamline the construction process while maintaining their image. Opus reticulatum required the use of quoins for its edges usually made of brick and stone which it could not do on its own.[2] Reticulate work and tufa related constructions also suffered from erosion as most stones were exposed to the elements which were liable to absorb moisture and condensation as most stones used were only moderately lithified.[3] Tufa also had a lower weight bearing load than stronger building materials.[4]

Such issues led to the rise of opus testaeceum, a facing using brick which was seen as more effective because it fulfilled Rome’s priorities of efficiency and ease or assembly.[1] The technique also worked well with opus caementicium and did not require the use of quoins for its edges compared to opus reticulatum.

Importance

Opus reticulatum is important in contributing to the understanding of Rome’s urbanisation and their need to streamline and ease the process of construction because of the social and economic evolution it underwent from the third century BCE.[1] While accommodating the environmental and architectural constraints of their territories because of their differing landscapes compared to Italy.[2]

The technique also provides the ability to estimate dates for architectural structures where explicit source for the dating does not exist for the construction.[3] This is due to the somewhat chronological order facing techniques are developed in.[4] Reticulate work can also be used for the basis of scholarly debate in particular Edmund Thomas’s discussion on the date of the ‘Villa Claudia’ at Anguillara Sabazia.[5] The usage of opus reticulatum in scholarly debate can also contextualise other architectural features which co-existed with the technique.[6]