Within the action A4 Design in detail of demonstrative textile prototypes, the design process has been carried out for the prototypes for the insoles, using digital lasts, and for the isolation materials for building, using 3D CAD software and implementing eco-design methodology. In parallel, the physical requirements of the insole and the isolator have been studied to be produced with the recycled polyester fibre. The productive processes have been analysed and parametrised for the previous manufacturing and to be able to foresee possible modifications in the production, due to the use of recycled PET.