The model is generated by extruding the plan to a height of six meters above the ground plane of the building interior, which is approximated horizontal throughout. The exterior ground plane in the model approximates the grading around the building. with the northeast exterior corner 0.5 to 1 meters below the interior grade, and the southeast corner 1.6 meters below the interior grade. The 1.6 meter difference at the southeast corner is compatible with the photogrammetric model, but is less than the 2.2 meter grade difference found in the more accurate survey model, described in appendix D.
The plan is derived from a two-dimensional AutoCAD drawing developed by Dobbins  and Hanna. This plan was derived from 1:400 drawings obtained from the architect's office of the Sopritendenza at Pompeii, which were derived from the well-known Eschenbach plan of Pompeii.
The assumed six meter wall height is an approximate estimate, based on a number of factors. First, as shown in figure B.1, the tops of beam pockets in the south shop walls at W49.50 are approximately 3.1 meters above grade, so that a similar second story would produce a height of roughly six meters.
Beam pockets in W18.17 (figure B.2) are lower, with their tops approximately 2.7 meters above the grade of the shops, which is approximately 1 to 0.5 meters lower than the interior grade at that point, raising the possibility that portions of the north wall may have been lower than other walls in the building, or that the shop walls did not extend as high as the perimeter wall.
The frescos at the northwest corner of the building (figure B.3) extend to a height slightly exceeding 5 meters, according to approximate photogrammetric measurements, and the incomplete state of the top of the frescos indicates that they extended higher.
|Figure B.4: Overall view of the east end of the Macellum, showing that the shrine is one of the highest points in the building.|
The assumed uniform six-meter height is undoubtedly a gross simplification of the actual configuration of the walls in ancient times, but is a reasonable approximation for the purposes of this study.