A method for manufacturing an electric cable joint comprising: - providing a first electric cable and a second electric cable, each cable (100; 200) comprising an electric conductor (10; 20) and a thermoplastic insulation system (12; 22) surrounding the electric conductor (10; 20), the thermoplastic insulation system (12; 22) comprising an inner thermoplastic semiconducting layer (14; 24), a thermoplastic insulating layer (16; 26) and an outer thermoplastic semiconducting layer (18; 28); - joining respective terminal portions of the electric conductors (10; 20) of the first electric cable and of a second electric cable placed axially adjacent to the first electric cable, to form an electric conductor joint; - surrounding the electric conductor joint with a joint inner layer of a first thermoplastic semiconducting material having a first dynamic storage modulus, E' 1, and submitting the joint inner layer to a heating step to a temperature suitable for melting the thermoplastic material thereof and for converting the material from the shape of a tape winding to a shape of a homogeneous cylinder; - surrounding the joint inner layer of a first thermoplastic semiconducting material with a joint insulating layer of a thermoplastic insulating material having a second dynamic storage modulus, E 2 ', and submitting the joint insulating layer to a heating step to a temperature suitable for melting the thermoplastic material thereof and for converting the material from the shape of a tape winding to a shape of a homogeneous cylinder; and - surrounding the joint insulating layer of thermoplastic insulating material with a joint outer layer of a second thermoplastic semiconducting material having a third dynamic storage modulus, E 3 ' and submitting the joint outer layer to a heating step to a temperature suitable for melting the thermoplastic material thereof and for converting the material from the shape of a tape winding to a shape of a homogeneous cylinder; characterised in that the first dynamic storage modulus, E 1 ', of the first thermoplastic semiconducting material of the joint inner layer is greater than the second dynamic storage modulus, E 2 ', of the thermoplastic insulating material of the joint insulating layer, the dynamic storage moduli, E 1 ', E 2 ', being measured at a substantially same measurement temperature of at least 130°C. - providing a first electric cable and a second electric cable, each cable (100; 200) comprising an electric conductor (10; 20) and a thermoplastic insulation system (12; 22) surrounding the electric conductor (10; 20), the thermoplastic insulation system (12; 22) comprising an inner thermoplastic semiconducting layer (14; 24), a thermoplastic insulating layer (16; 26) and an outer thermoplastic semiconducting layer (18; 28); - joining respective terminal portions of the electric conductors (10; 20) of the first electric cable and of a second electric cable placed axially adjacent to the first electric cable, to form an electric conductor joint; - surrounding the electric conductor joint with a joint inner layer of a first thermoplastic semiconducting material having a first dynamic storage modulus, E' 1, and submitting the joint inner layer to a heating step to a temperature suitable for melting the thermoplastic material thereof and for converting the material from the shape of a tape winding to a shape of a homogeneous cylinder; - surrounding the joint inner layer of a first thermoplastic semiconducting material with a joint insulating layer of a thermoplastic insulating material having a second dynamic storage modulus, E 2 ', and submitting the joint insulating layer to a heating step to a temperature suitable for melting the thermoplastic material thereof and for converting the material from the shape of a tape winding to a shape of a homogeneous cylinder; and - surrounding the joint insulating layer of thermoplastic insulating material with a joint outer layer of a second thermoplastic semiconducting material having a third dynamic storage modulus, E 3 ' and submitting the joint outer layer to a heating step to a temperature suitable for melting the thermoplastic material thereof and for converting the material from the shape of a tape winding to a shape of a homogeneous cylinder; characterised in that the first dynamic storage modulus, E 1 ', of the first thermoplastic semiconducting material of the joint inner layer is greater than the second dynamic storage modulus, E 2 ', of the thermoplastic insulating material of the joint insulating layer, the dynamic storage moduli, E 1 ', E 2 ', being measured at a substantially same measurement temperature of at least 130°C.