Abstract: An adjustable hinge assembly is provided for use on a ventilator apparatus, wherein the ventilator apparatus includes a curb, a removable curb cap covering the curb and presenting side and rear edges, and a ventilator supported on the curb cap. The assembly includes a pair of laterally spaced curb cap support plates that each include a first arm adapted to be secured to the curb cap and extending along one of the side edges of the cap, and a second arm adapted to be secured to the curb cap and extending along the rear edge of the cap. The assembly also includes a back plate connected to and between the support plates along the rear edge of the cap, and a pair of laterally spaced curb plates adapted to be secured to the curb. The curb plates support the curb cap support plates, and define a pivot axis about which the curb cap support plates pivot between a first position in which the cap covers the curb, and a second position in which the cap is raised from the curb.