Contemporary building envelopes primarily rely on repetitive elements that fulfill mainly a singular purpose - a barrier between interior and exterior spaces. Implementing building envelopes featuring intricate geometries and non-repetitive tiles can significantly enhance the environmental performance of the structure. However, the current manufacturing processes for the required moulds are plagued by high costs, time consumption, labor-intensiveness, and mainly by using non-recyclable moulds. To address these challenges, the paper presents an innovative solution for designing and fabricating building envelope tiles with complex geometries by employing stay-in-place 3D knitted moulds. The moulds are digitally fabricated using innovative knitting procedures implemented on an industrial flat double-bed machine. The paper presents preliminary research outcomes, including a new digital design methodology for creating knitted moulds and a new fabrication method for buildings’ envelope tiles.