A process for the manufacture of windows/ doors, characterized by the fact that it comprises the following steps: • - providing at least one inner panel for windows/doors; • - providing a plurality of plastic profiled elements (3) for windows/ doors, each of the profiled elements (3) comprising at least two areas to seal (5), coupleable to the areas to seal (5) of the other profiled elements (3), and at least one longitudinal slot (6), in which a respective perimeter side of the inner panel is insertable; • - performing a step of mechanical machining by chip removal on at least one of the areas to seal (5); • - heating the areas to seal (5); • - coupling the heated areas to seal (5) to one another by pressing the profiled elements (3) one against the other to maintain the areas to seal (5) in mutual contact and define the frame for windows/doors, the coupling taking place with the inner panel inserted in the longitudinal slots (6) to define a window/door which is composed by the frame and by the inn
