The framework comprises a U-shaped body, with a number of identical flat and transverse ribs (1) that are uniformly spaced out, and are grouped in pairs by means of longitudinal ridges (2) located at two imaginary longitudinal axes A and B that are in turn located on the lateral walls of the U-shaped body, while the various pairs of ribs (1) are attached to each other by means of other longitudinal ridges (3) that are in turn located on a single longitudinal axis C, positioned on one of the lateral faces of the U-shaped body. The framework may be used in weather-strip sections for motor cars and the like. The weather-strip section' s longitudinal contraction and stretch is directly proportional to the distance between axes A and C.