On-site design decisions at the Basilica of Maxentius in Rome

The design provides a decisive component and basis for all subsequent building processes, the substance of communication between planning and realisation. This applies not least to the imperial projects of Roman antiquity. But we still have limited knowledge of the Roman design processes, which since Wilson Jones' "Principles of Roman Architecture" (2000) must at least be considered fluid. Using the late antique Basilica of Maxentius in Rome as a case study, the moments when design decisions were made can be determined very precisely at several points. The assumption that the design work was already completed when construction began can be clearly refuted here. Numerous proven deviations from the regular design scheme at various levels show that the final detailed design must first have been developed 1:1 on the construction site.