Abstract: A construction assembly for installing a roller blind or the like comprising two parallel guiding sets spaced at a predetermined distance, between which at the least a roller blind can be slid in a guided manner, the at the least roller blind being arranged in the upper part of the two guiding sets. This construction assembly comprises an internally hollow outer profile that can be fastened to a vertical surface, an internally hollow inner profile that is arranged in the interior of the outer profile, the inner profile having dimensions such that it is insertable into a housing defined by the outer profile by means of a snap fit, and a retaining element configured to retain a longitudinal edge of the roller blind arranged longitudinally along the inner profile.