Primarily found preserved in subterranean structures, mainly tombs. Due to the denuded conditions of Ancient Near Eastern buildings in general, relatively few examples for the use of vaulting as a means of covering spaces above ground are known, though the technical expertise which produced the underground vaults would have been applied more generally. By analogy with contemporary Near Eastern building traditions, and considering certain architectural dispositions, vaulted spaces were probably much more common than it appears from archaeological records alone. Thick walls enclosing relatively narrow transverse spaces were probably roofed by brick vaults rather than the much lighter flat roofs composed of timber and mudplaster. The advantages of vaults are primarily economical: they were cheaper to build and easier to maintain than flat roofs, and they provided higher internal spaces which could be lighted by clerestory windows.
The most widespread techniques of vaulting avoided the use of CENTRING. The high cost of the relatively great quantity of timber required for the temporary structures would have made them too expensive. Most popular for small rooms in private houses throughout the Near East was the corbelled vault. As in the corbelled dome, it distributes the weight gradually over the individual components of the structure, since each brick or stone receives the load of the projecting one above (eg in some of the mid-3rd millennium Royal Tombs of UR, the gatehouse at Tell Taya—see Reade, J., Iraq 30, p. 247; the posterns of Alishar, BOGHAZKÖY and RAS SHAMRA (2nd millennium BC); tomb 3 at MEGIDDO).
The earliest surviving examples of barrel vaults or tunnel vaults in brick were found in I Dynasty tombs in Egypt (tomb 3357 in SAQQARA). They were more commonly employed in the New Kingdom and the later periods (especially during the Graeco-Roman). They were used mainly to cover broad halls or corridors and were constructed either with a centring of wood or sand infill (in small structures), or by inclined courses resting against an arch or temporary wall. The voussoirs could be edge-shaped or curved but conventional, rectangular bricks were used more often, with small stones or sherds filling the gaps between them on the outside curve. The bricks usually had a higher proportion of chaff-temper than ordinary bricks to make them lighter. Finger-marks or vertical grooves along the surface allowed them to stick together by suction. The average span of a brick barrel vault was c. 3.25m; the largest recorded span, 8.60m, occurred in the royal stables at MEDINET-HABU. The best-preserved Egyptian brick vaults were found in the magazines surrounding the mortuary temple of Ramesses II (Ramesseum) in western Thebes—they were four bricks thick and spanned about 4m.
Ribbed vaults may have originated from curved reed-structures supported by rings of bundled reeds. A series of semi-circular