High efficiency louvre diffusers serve to improve the general effectiveness of ventilation systems. They have unique louvre configurations that will increase the intake of air into the lavatory or any other room and facilitate better mixing of air and subsequently better uniformity of break out into the environment. Higher efficiency of the ventilation system is achieved by these diffusers because less conditioned air will be resisted by the ducts and most of it will be smoothly inserted through the ducts. Like most powerful devices such as data centers, laboratories, and large commercial buildings, they require accurate control over temperature and effective distribution of the air.