A device for leading pipes (6) of a solar cell through a roof, which device is characterized by a connecting sleeve having an upper end with an annular cross section, the connecting sleeve being mounted onto the straight-cut upper end of a dome-like collar (2a) of a conventional pipe duct (2) to surround the opening of the collar (2a), as well as by a cap (4) turnably installed on the upper end of the connecting sleeve (3) and provided with a sideward-facing receiving opening (5) for pipes (6) to be led from a solar cell into the building, whereby the receiving opening (5) is sealable around the pipes (6).