Assembly for building into a wall, and method for building in such an assembly

The present invention provides an assembly for building into a wall, especially a prefabricated or prefab wall. The assembly comprises a mounting box (10), an insert part (20) mountable in the mounting box (10) and comprising a functional module (21) connectable with at least one cable (50). The assembly furthermore comprises a cover element (40) mountable on the insert part (20) after building the mounting box (10) into the wall. The mounting box (10) and the insert part (20) are adapted for being able to position the insert part (20) at least in a building-in position and a use position and for moving the insert part (20) from the building-in position to the use position. The assembly furthermore comprises a cover (30) for closing off an open side of the mounting box (10)in the building-in position of the insert part (20). The cover (30) is provided with a coupling means (31, 32) for coupling the cover (30) to the insert part (20), the coupling means (31, 32) being designed to pull the insert part (20) from the building-in position to the use position when removing the cover (30).