The article analyzes some issues of computer variant dynamic forming of building structures on the basis of poliparametrization method. This method is a further development of the theory of structural-parametric geometric modelling, which was worked out in NTUU "I. Sikorsky KPI" and now is being successfully developed and improved together with scientists from RUDN University. This paper studies the possibility of using the poliparametrization method for forming midline surfaces of building shells in order to ensure their effective automated prototyping. Also some as examples are given to demonstrate the appropriate mathematical and computer models for dynamic variant forming of thin-walled spatial building structures.