Pompeii offers a unique insight into the architecture and construction techniques of the Roman world. Thanks to its admirably preserved buildings, archaeologists have been able to reconstruct the evolution of building techniques used over the centuries, from the pre-Samnite period to Roman times.
The Building Materials
The first inhabitants of Pompeii, in the pre-Samnite period (c. 550-425 B.C.), used locally available materials such as lava cruma, reddish in color and porous in appearance, and pappamonte, a black granular tuff of volcanic origin. Pappamonte, in particular, was used for the construction of the first city walls.
With the arrival of the Samnites, beginning in the fourth century B.C., the use of limestone from the Sarno valley, a stronger material than pappamonte, was introduced. The limestone blocks, carefully squared, were arranged in regular rows according to the technique of opera quadrata .
The Innovation of the Cement Opera
Around the 3rd century BC, the use of opera cementizia (opus caementicium) became widespread in Pompeii, an innovative technique that revolutionized Roman construction. Cementitious work consisted of a mixture of lime and volcanic sand (pozzolan), which acted as a binder for stone fragments of various sizes called caementa. This technique, praised by Vitruvius for its strength, enabled the construction of more solid and complex structures, such as vaults and arches.
From the Opera Incerta to the Perfect Grid
Another construction technique widely used in Pompeii was the opera incerta (opus incertum), characterized by a face of irregular stones. Beginning in the first century B.C., this technique evolved into the quasi reticulated opus (opus quasi reticulatum), in which the stone fragments took on a more regular shape, tending to create a lattice pattern.
With the arrival of the Romans in 80 B.C., the use of opus reticulatum (opus reticulatum) became widespread, which was a refinement of quasi-reticulated opus. In this technique, tuff blocks, cut in the shape of a pyramid, were arranged to create a perfect lattice. Lattice work, which was particularly expensive, was used mainly in prestigious buildings.
The Introduction of Brickwork
Beginning in the Augustan Age (27 BC), the use of laterizi (opus latericium) as a facing for walls became widespread in Pompeii. The bricks, square or triangular in shape, were used to reinforce the corners of buildings, to construct pillars and columns, and to make vaults and arches. The spread of bricks was favored by the presence of clay and volcanic sand around Pompeii.
The Mixed Opera: A Combination of Techniques.
Mixed opera (opus mixtum) combined several construction techniques, such as reticulated opera and the use of bricks. This technique, however, did not spread to Rome until after the eruption of AD 79, so it is difficult to find examples of it in Pompeii.
Conclusions
The construction techniques used in Pompeii reflect the evolution of Roman architecture over the centuries. The city's exceptional preservation provides a unique opportunity to study the different building techniques, materials used, and ingenuity of the ancient builders.
FAQ on Construction Techniques in Pompeii.
1. What were the most commonly used building materials in Pompeii?
Pompeians used a variety of materials to build their houses and public buildings. Some of the most common include:
Volcanic stone: Volcanic materials were abundant in the region around Mount Vesuvius and were widely used in Pompeii.
“Lava cruma,” reddish in color and porous, was extracted from the surface layer of lava.
“pappamonte,” a black granular tuff, was used for the city's early walls.
Limestone: Beginning in the fourth century B.C., limestone from the Sarno Valley became a popular building material. It was stronger than pappamonte and was used to make square blocks arranged in regular rows (“opera quadrata”).
Nocera tuff: Around 100 B.C., Nocera tuff was introduced in Pompeii. It had a compact structure that lent itself well to the creation of ornamental details.
Bricks: During Roman times, bricks became increasingly common. They were used as wall coverings, to construct columns and arches, and to make vaults.
Mortar: Mortar, a mixture of lime and volcanic sand, was the binder used in cement work and other techniques. Vitruvius praised it for its strength and resistance.
2. What were the main construction techniques used in Pompeii?
Opera quadrata: This technique, used since pre-Roman times, involved the arrangement of squared stone blocks in regular rows.
Opera cementizia (Opus Caementicium): This innovative technique involved the use of a mortar made of lime and volcanic sand (pozzolan) as a binder for stone fragments (caementa). It allowed the construction of larger and more complex structures, such as vaults and domes.
Opera incerta (Opus Incertum): Characterized by a facing of irregular stones, opera incerta was an older and less expensive technique than reticulated opera.
Opera quasi reticulatum (Opus Quasi Reticulatum): An evolution of opus incerta, the stone fragments in this technique were more regular and arranged to create a rough lattice pattern.
Reticulated work (Opus Reticulatum): This technique involved arranging blocks of tufa in the shape of a pyramid to create a perfect lattice. It was an expensive and prestigious technique used for the most important buildings.
Lateritic Opera (Opus Latericium): The use of bricks as wall cladding and for the construction of architectural elements became common during Roman times.
Mixed Opera (Opus Mixtum): This technique combined several techniques, such as reticulated opera and brickwork. It was a relatively late technique that spread to Rome after the eruption of 79 AD.
3. How did earthquakes affect construction techniques in Pompeii?
Pompeii was hit by a major earthquake in 62 AD, which caused significant damage to buildings. Pompeiians had to rebuild and repair their houses and used a variety of techniques to do so, including the use of bricks and mixed-media work. Sources suggest that not all houses were rebuilt after the earthquake, and some central areas of the city were abandoned.
4. Are there specific examples of buildings in Pompeii that show different construction techniques?
Yes, many buildings in Pompeii show the use of different construction techniques. For example:
The city walls: The earliest walls were built with “pappamonte,” while the later ones were built of limestone using the “opera quadrata” technique.
The Amphitheater: The amphitheater was built with the “opera incerta” and the “opera quasi reticulatum.
The Basilica: The Basilica features triangular brick columns.
Private houses: Many houses show the use of different techniques, depending on their date of construction and the social status of the owners. Wealthier houses often used lattice work for their facades.
5. How did Pompeii's construction techniques compare with those of other Roman cities?
Construction techniques in Pompeii were generally in line with those used in other Roman cities. The use of concrete work, lattice work, and bricks was widespread throughout the Roman Empire. However, some specific details and variations can be observed in Pompeii due to the local materials available and the cultural influences of the region.
6. Is there anything else I should know about construction techniques in Pompeii?
In addition to the techniques mentioned above, other interesting aspects of Roman construction can be observed in Pompeii:
The use of wood: Although wood was not well preserved in Pompeii, sources suggest that it was widely used for roofs, ceilings, and other structural elements.
Plumbing: Pompeiians had developed sophisticated hydraulic systems for supplying water to houses, public fountains, and baths. The Augustan aqueduct, built in the early imperial age, supplied fresh water to the city from distant springs.
Decoration: Pompeians decorated their houses with frescoes, mosaics, and stucco. Decorative techniques and styles varied over time, reflecting the fashions and artistic influences of the time.
The study of construction techniques in Pompeii offers a fascinating window into the daily life, culture and technology of the Roman world. The city, frozen in time by the eruption of Vesuvius, continues to fascinate and teach archaeologists and visitors today.
Essential bibliography:
T. e J. P. Adam, Le tecniche costruttive a Pompei, in Pompei 1748 - 1980. I Tempi della Documentazione, Roma 1981
AA.VV., Pompei, vv. I-II, Napoli 1992
G.Lugli, La tecnica edilizia romana con particolare riguardo a Roma e Lazio, Roma 1957