A solar heat collector roof comprises an absorber plate for incident radiation energy and a heat exchange plate placed directly thereunder. The heat exchange plate is corrugated in such a manner that it comprises channels extending down along the roof. The heat exchange plate is moreover in direct contact with the absorber plate thereabove. A heat carrying or heat removing liquid medium, e.g. water, flows in the channels. The liquid medium, which removes heat from the heat exchange plate, is supplied at such a rate that the flow rate down along the roof in the channels lies below the rate at which the surface tension of the heat carrying medium is broken, so that a winding and travelling flow pattern is imparted thereby to the liquid medium, and up along the channel walls.