A door assembly comprises a door (1) and second body (2) each having an internal cavity and pivotably secured together by a hinge (3) with an internal channel. Another door assembly comprises a first and second body each having an internal cavity, a hinge projecting from the first body and having an internal channel in fluid connection with the first body cavity, a pin projecting from the second body into the hinge channel to pivotably secure the hinge and second body together such that the hinge channel and second body cavity are in fluid connection. Each assembly is adapted to receive a conduit (6) connecting the internal cavities via the hinge channel. In each assembly, the second body comprises an extruded hollow panel including a substantially cylindrical extruded channel that aligns with the hinge channel to form a continuous shaft. A cabinet including such a door assembly is also described.