Forensic examinations aimed at justifying (designing) the dimensions and configuration of land plots under buildings or structures are carried out as part of land-related judicial disputes concerning the allocation, clarification or division of such plots. The paper examines the circumstances under which these tasks should be addressed by a construction and technical expert, and when by a land-surveying expert. In addition, the paper provides a general characterization of this type of examination, summarizing its object, subject matter, tasks, and procedural algorithm. Attention is given to two approaches that an expert may use when responding to a court’s inquiry: the calculative (design-oriented) approach and operational approach. Within the latter, three distinct avenues for conducting the expert examination are considered: based on setback requirements, based on the building coverage ratio, and based on actual usage. The author concludes that in order to ensure the completeness, an expert’s report should present options prepared using all these approaches.