The study presented in this paper was carried out to verify the eff ectiveness of the individually developed acoustic optimisation method. Documentation and own measurements of an existing post-industrial building – a grain elevator in Płock – were used. The method of iterative search for the geometric form of the interior was used to design a concert hall inscribed in its structure. The criteria for assessing the quality of the generated solutions were the acoustic parameters obtained (reverberation, initial time delay gap, uniform coverage of the auditorium with reflected sound, and the quotient of the hall volume and the number of seats in the auditorium). As a result of the optimisation, variants of the auditorium’s interior design were created. These were evaluated against reference architectural realisations. The results of the study allowed the authors to confirm the effectiveness of the method (the optimisation results were in line with the reference halls in many points). They also provided a picture of the existing limitations, being a premise for further improvements to the method. The authors intend to use the results in further work on parameterisation of architectural models and on the use of generative engines in optimisation. In the longer term, after refinement, there is a chance to use the method in real creative activities.