Abstract: A method and a plant (1) for the production of a membrane body (10) that is flexible and able to assume a given shape under load; the membrane body being provided with at least one pair of flexible sheets (9) mutually coupled through an adhesive layer (14) positioned between mutually facing respective faces (16) of the sheets (9); the method comprising a step of die casting a portion (11) of given extension of the membrane body (10) to determine adhesion between the faces (16) and to form at least one sheath (22) with an external tubular portion of a respective cable (20); the step of die casting the portion (11) being achievable by thermal activation of the adhesive layer (14) in a static manner.