Cavaedium

The etymology of "cavaedium", "cavum aedium", and "atrium" is debated. These terms are thought by many to be synonymous; others have argued that one term includes the impluvium and the other does not, but are not agreed upon which. Varro gives classical etymologies: "The hollow of the house (cavum ædium) is a covered place within the walls, left open to the common use of all. It is called Tuscan, from the Tuscans, after the Romans began to imitate their cavædium. The word atrium is derived from the Atriates, a people of Tuscany, from whom the pattern of it was taken." For more modern etymologies, see :Wiktionary:atrium. ==Uses==

Light, water, air and cooling , and opus sectile impluvium, House of Publius Servilius Casca Longus (close-up) Roman townhouses rarely had windows, as they often had very little exterior wall. Where present, windows were placed above eye-level, and they were small The tollere liberum (ceremony for a newborn), dedication of the bulla at Liberalia (coming-of-age, male), and confarreatio marriage were described as conducted in the atrium, in front of the lararium. The wedding couch or bed, the lectus genialis, was placed in the atrium, on the side opposite the door or in one of the alae. The lectus funebris, or funeral couch, was placed in the atrium, and the body of the deceased was laid in state upon it with feet facing the door. It was thus a sort of living-room. Spinning and weaving, major household tasks, were traditionally done in the atrium, The homes of the richest Romans became more ostentatious as increasing wealth inequality increased housing inequality, and as it became less socially important to display frugalitas and abundentia, and more important to display tryphé. This patron-class use as a reception-room made the atrium a semi-public space, The pars rusticana was centered around a peristyle; it did not exist in early Roman houses. Greek culture was high-status in Roman culture (see Hellenization). The peristyle was borrowed from Greek architecture and became popular, eventually sometimes replacing the atrium. In the countryside the order was sometimes reversed; the pars urbana cortile, which one entered from the main street entrance, was a peristyle. The atrium was then buried in the depths of the house, often near a portico (an outwards-looking colonnade on one or more outside walls) with a view of the landscape. ==Contents==

The atrium often contained a small chapel to the ancestral spirits (lararium). The household safe (arca) was also kept in the atrium; it contained family treasures and important documents. A puteal, a low cylindrical covered wellhead through which water could be drawn from the cistern below, was often present. There would also be works of art, especially statuary, which was set beside the impluvium, on tables, in niches, on walls, etc. For night, there might be oil-lamp-stands. Curtains or partitions might close off the tablinum; alae might also have been curtained at times. Interior doorways might have doors or curtains. ==Compluvium==

The roof is framed so as to leave an open space in the center, known as the compluvium. The rain from the roof was usually collected in gutters around the compluvium, and discharged thence into the impluvium. The roof around the compluvium was edged with a row of highly ornamented tiles, called antefixes, on which a mask or some other figure was moulded. At the corners there were usually spouts, in the form of lions' or dogs' heads, or any fantastical device which the architect might fancy. The spouts carried the rain-water clear out into the impluvium, rather than letting it run down the walls and pillars, which would damage them. Seeping through the bottom of the impluvium, the water passed into cisterns, from which it was drawn for household purposes. The compluvial opening might be shaded by a coloured veil, probably of an open, airy weave. ==Roof structure==

of a Tuscan atrium (see below for 3D photos) a, a. Side walls. b. One of the two girders supporting the roof. c. Crossbeam, resting on the two girders. d. Short beam of the thickness of c. e. Corner beam. f. Rafters, sloping toward the inside. g. Compluvium, a hole open to the sky. 1. Flat tiles, tegulae. 2. Semicylindrical tiles for covering the joints, imbrices. 3. Gutter tiles. Five structural types of cavaedia (or atria) are described by the architect Vitruvius: • The atrium tuscanicum has no pillars; beams span the entire room, framing a rectangular hole in the center and supporting the roof (commonest) • The atrium corinthium has (more than four) pillars along the edges of the roof opening (newly fashionable in Vitruvius' time) • The atrium tetrastylum has four pillars at the corners of the roof opening (not common These pillars support a beam, which supports a wall, which in turn supports the rafters in the middle of the atrium. There is no need for horizontal beams spanning the entire room; the rafters have shorter spans. This allows a larger room to be roofed. File:Villa San Marco 2.JPG|Atrium tetrastylum, four pillars. Villa San Marco, Stabiae. In this image, the atrium is roofed by a white tarp, laced down at the eaves and supported by scaffolding. File:Il pozzo di luce.jpg|Same, but with a reconstructed roof. The lack of plaster shows how four horizontal beams, running between the four columns, support a short masonry wall (opus incertum), which in turn supports the rafters File:A Roman Interior by Luigi Bazzani, before 1927.jpg|The figure is leaning against the cartibulum, the lararium is against the wall behind her, and the statue to her right is a small fountain cascading into a shallow trough and thence into the impluvium. File:Gustave Boulanger - Répétition du "Joueur de flûte" et de la "Femme de Diomède" chez le prince Napoléon - Orsay RF 1550.jpg|Atrium tetrastylum (not a very accurate reconstruction) Corinthian cavaedium File:Casa_del_Menandro_Pompeii_20_dodged.jpg|Atrium corinthium, multiple pillars. Small atrium of the House of Menander, Pompeii. Note how the diagonal valley rafters, at the mitered corners, are set lower than the smaller orthogonal rafters. This atrium is smaller than the clear-span Tuscan main atrium in the same house (floorplan model). File:MJK09199 Pompejanum.jpg|Pompejanum reconstruction (glass roof is an unrealistic modern addition), loosely based on the square atrium in the House of Castor and Pollux, Pompeii (floorplans) File:Casa dell Atrio Corinzio (Herculaneum) 02.jpg|House of the Corinthian Atrium, in Herculaneum. The six pillars are stuccoed tufa, repaired with brick. This atrium is halfway to being a peristyle; planters flank a grassy area. The central marble fountain was fed by an aqueduct, making the original purpose of the atrium, a structure for gathering rainwater, superfluous. The original well remains, beside the nearest pillar (floorplan). File:Sudika Rabat Domus Romana.jpg|16-column peristyle atrium of the Domvs Romana, in Malta (1st century BC). Note puteal and overflow hole of impluvium. File:Ancient Delos.jpg|Atrium with puteal, House of the Lake, Roman-era Delos. Delos was short on freshwater and atria there generally collected it. File:Delos_Haus_des_Hermes_01.jpg|Two stories of Corinthian atria/peristyles. House of the Hermes, Roman-era Delos. This style has a rectangle of pillars around the roof opening. It is like the tetrastyle, but with more than four pillars. It resembles a peristyle. If the lower layer was sufficiently robust, it could support a second story. Displuvial cavaedium In this style, the roofs, instead of sloping down towards the compluvium, sloped outwards from the compluvium, the gutters being on the outer walls; there was still an opening in the roof, and an impluvium to catch the rain falling through (and presumably fed by the gutters). This species of roof, Vitruvius states, is constantly in want of repair, as the water does not easily run away, owing to the stoppage in the rainwater pipes. This type was rare; only one had been found in Pompeii, . File:Atrium impluviatumum.png|Impluviate atrium File:Atrium displuviatumum.png|Displuviate atrium (rare) File:Baigneux-les-Juifs - Lavoir 2.jpg|Functioning compluvium roof in the 1865 lavoir (public laundry-house), Baigneux-les-Juifs, France File:Vitteaux - Lavoir 1.jpg|Similar lavoir from outside Testudinate cavaedium The atrium testudinatum was employed when the atrium was small and another floor was built over it. The name comes from the Latin word , which means a turtle or tortoise, and by transference a covered vault. The Encyclopædia Britannica said that no example of this type had been found at Pompeii, . While narrow homes had atria that were not flanked by cubiculums and alae, and even atria where the impluvium was set against a wall or in a corner, homes smaller than 5 meters across are generally testudinate. ==Proportions==

Vitruvius continues by giving the correct proportions for an atrium (length:width ratios for the atrium, and their proportion to that of the opening in the roof, width:height ratios for the atrium, and the proportions (relative to the atrium) of the adjacent rooms that are alcoves open on the atrium side, the tablinum and alae). It is worth noting that many extant atria do not follow his ideal rules. {{blockquote|text=3. In width and length, atriums are designed according to three classes. The first is laid out by dividing the length into five parts and giving three parts to the width; the second, by dividing it into three parts and assigning two parts to the width; the third, by using the width to describe a square figure with equal sides, drawing a diagonal line in this square, and giving the atrium the length of this diagonal line. 4. Their height up to the girders should be one fourth less than their width, the rest being the proportion assigned to the ceiling and the roof above the girders. The alae, to the right and left, should have a width equal to one third of the length of the atrium, when that is from thirty to forty feet long. From forty to fifty feet, divide the length by three and one half, and give the alae the result. When it is from fifty to sixty feet in length, devote one fourth of the length to the alae. From sixty to eighty feet, divide the length by four and one half and let the result be the width of the alae. From eighty feet to one hundred feet, the length divided into five parts will produce the right width for the alae. Their lintel beams should be placed high enough to make the height of the alae equal to their width. 5. The tablinum should be given two thirds of the width of the atrium when the latter is twenty feet wide. If it is from thirty to forty feet, let half the width of the atrium be devoted to the tablinum. When it is from forty to sixty feet, divide the width into five parts and let two of these be set apart for the tablinum. In the case of smaller atriums, the symmetrical proportions cannot be the same as in larger. For if, in the case of the smaller, we employ the proportion that belong to the larger, both tablina and alae must be unserviceable, while if, in the case of the larger, we employ the proportions of the smaller, the rooms mentioned will be huge monstrosities. Hence, I have thought it best to describe exactly their respective proportionate sizes, with a view both to convenience and to beauty. 6. The height of the tablinum at the lintel should be one eighth more than its width. Its ceiling should exceed this height by one third of the width. The fauces in the case of smaller atriums should be two thirds, and in the case of larger one half the width of the tablinum. Let the busts of ancestors with their ornaments be set up at a height corresponding to the width of the alae. The proportionate width and height of doors may be settled, if they are Doric, in the Doric manner, and if Ionic, in the Ionic manner, according to the rules of symmetry which have been given about portals in the fourth book. In the roof-opening let an aperture be left with a breadth of not less than one fourth nor more than one third the width of the atrium, and with a length proportionate to that of the atrium. He also advises that the size of the atrium of cavaedium be appropriate to the purposes required by the owner's social station: "men of everyday fortune do not need entrance courts, tablina, or atriums built in grand style, because such men are more apt to discharge their social obligations by going round to others than to have others come to them... For capitalists and farmers of the revenue, somewhat comfortable and showy apartments must be constructed, secure against robbery; for advocates and public speakers, handsomer and more roomy, to accommodate meetings; for men of rank who, from holding offices and magistracies, have social obligations to their fellow-citizens, lofty entrance courts in regal style, and most spacious atriums and peristyles, with plantations and walks of some extent in them, appropriate to their dignity." In many homes in Pompeii, the atrium's walls were placed halfway between the walls behind them and the edge of the impluvium. This meant that the same proportions (almost always 1:√2 width:length) were used for the impluvium edge, the atrium walls, and the next layer of walls (those running outside the tabernae, the cubicles and alae, and the tablinum with its flanking rooms). This arrangement would give the sloping rafters an equal span on each side of the atrium walls. ==See also==