Abstract: A lavatory unit (10) comprising a tank body (12) connected to a pressurised water supply (20), and flushing means (14, 21, 23) for releasing water from the tank body via an outlet to a lavatory bowl (11). The flushing means includes an elastic bladder (21) the interior of which is in communication with the tank, the tank being generally sealed otherwise, such that the bladder stressed with the expansion of air forced from the tank as the tank fills with water and the bladder relaxes elastically as the tank empties, and thereby assists in ejecting the water under pressure from the tank to provide a better flushing action.