Abstract: This invention provides a roof in which plurality of louver-type roof plates are designed to be opened and closed by means of a reciprocating connecting rod pivoted to cranks secured to said roof plates. A ratchet gear mechanism is mounted to connect with the said connecting rod through a crank shaft so that the said ratchet gear may rotate tooth by tooth to adjust the roof plates stepwise between a fully open and a fully closed condition. An accommodation for draining rainwater from the roof is disclosed, as are several designs of roof plates.