The invention relates to a building-services unit (10), which includes a body component (12), a cover component (16) arranged to be attached to the body component in order to close the building-services unit, and inside which building-services unit elongated pieces (14) can be fitted. The cover component (16) includes edge bends (20) in the longitudinal direction (L) of the building-services unit, stiffening shaping (15) is fitted between the edge bends, and the building-services unit includes magnetic fastening (30) for attaching the cover component to the body component, which, when the building-services unit is assembled is in connection with at least one of the edge bends. The invention also relates to a building-services-unit system, a method for manufacturing a building-services unit, and the use of a building-services unit.