Water resistant footwear and manufacturing method

A water-resistant footwear comprising:

• an upper formed of a material that is water vapor transpiring and water resistant, said upper having a first flap and a second flap and at least one portion having a thickness, each of the first flap and the second flap having a respective thickness less than the thickness of the at least one portion;
• a thermo-double-sided adhesive layer interposed between the first flap and the second flap, wherein said thermo-double-sided adhesive layer is activatable by an increase in temperature applied thereto, wherein the first flap and the second flap are heat-sealed to each other by said thermo-double-sided adhesive layer;
• a lining fixed to said upper so as to directly face an internal face of said upper;
• an insole affixed to an edge of said upper;
• a waterproof sole directly injection molded onto said upper so as to cover one face of said insole in sealing relation thereto;
• an under-tongue element fixed by a seam to a first portion of the internal face of said upper;
• and
• a tongue having a fixed edge affixed and heat sealed to a second portion of an outer face of said upper by another thermo-double-sided adhesive layer, the another thermo-double-sided adhesive layer being activatable by a temperature increase applied thereto, wherein said tongue has a free edge unfixed with respect to said upper, the free edge being a greater distance from said insole than a distance of the fixed edge of said tongue from said insole, said tongue extending so as to overlap said under-tongue element and to cover the seam, wherein the fixed edge surmounts the second portion of the outer face of said upper.