Abstract: A sill cock assembly is disclosed comprising a fluid outlet for location on the exterior of a wall, a fluid flow inlet adapted for location adjacent the interior of the wall, a conduit connecting the fluid inlet and the fluid outlet, a selectively operable valve located adjacent the fluid flow inlet for alternatively opening and closing the fluid flow inlet, and a pressure release means located adjacent the valve to allow fluid communication in an inwardly direction from the conduit through the valve to the fluid inlet when the fluid pressure within the conduit due to freezing is greater than the fluid pressure of the inlet. A portion of the wall of the conduit is corrugated adjacent the valve to allow expansion of the conduit during freezing.