A housing assembly (1, 100) comprising: - a raceway for holding electrical wires or the like comprising a bottom wall and two side walls (3, 3') extending from said bottom wall, the bottom wall and the two side walls (3, 3') defining an housing seat for the electrical wires or the like, said side walls (3, 3') being provided with respective first fixing means; - a fitting comprising second fixing means (104, 105) suitable to engage said first fixing means in order to apply the fitting to the raceway, said fitting comprising a first and second tract joined by a main tract, said first and second tract being substantially transversal to said main tract, said second fixing means (104, 105) comprising ribs (104, 104') formed on an inner surface of said main tract, said ribs protruding from the inner surface in a direction substantially perpendicular to the main tract, characterised in that said first fixing means comprise support means and friction means distributed on the support means, said support means comprising, for at least one of said side walls, an end portion of the corresponding side wall, said friction means being made of a material having a first rigidity different from a second rigidity associated to the support means, said friction means comprising, for at least one of said side walls, a flap extending parallel to at least a part of a longitudinal axis of the raceway and such as to have a side joined to the end portion and an opposite side free, which faces the housing seat, and in that said flap is interposed between said first fixing means and said ribs (104, 104') when the fitting is applied to the raceway, said ribs (104, 104') of the fitting pressing against the flap of the side wall. - a raceway for holding electrical wires or the like comprising a bottom wall and two side walls (3, 3') extending from said bottom wall, the bottom wall and the two side walls (3, 3') defining an housing seat for the electrical wires or the like, said side walls (3, 3') being provided with respective first fixing means; - a fitting comprising second fixing means (104, 105) suitable to engage said first fixing means in order to apply the fitting to the raceway, said fitting comprising a first and second tract joined by a main tract, said first and second tract being substantially transversal to said main tract, said second fixing means (104, 105) comprising ribs (104, 104') formed on an inner surface of said main tract, said ribs protruding from the inner surface in a direction substantially perpendicular to the main tract, characterised in that said first fixing means comprise support means and friction means distributed on the support means, said support means comprising, for at least one of said side walls, an end portion of the corresponding side wall, said friction means being made of a material having a first rigidity different from a second rigidity associated to the support means, said friction means comprising, for at least one of said side walls, a flap extending parallel to at least a part of a longitudinal axis of the raceway and such as to have a side joined to the end portion and an opposite side free, which faces the housing seat, and in that said flap is interposed between said first fixing means and said ribs (104, 104') when the fitting is applied to the raceway, said ribs (104, 104') of the fitting pressing against the flap of the side wall.