A body part of a vehicle, the body part having: an outer sheet that will
form a part of the vehicle exterior surface; an inner part disposed
between the outer sheet and the passenger compartment when the body part
is assembled to the vehicle; a first infrared radiation reflecting layer
on the outer surface of the outer sheet; and a second infrared radiation
reflecting layer on the surface of the inner part that faces the outer
sheet. The inner part includes a thermal insulation material. The outer
sheet and the inner part delimit an air flow path for supporting a flow
of air adjacent the outer sheet and in the direction of the length of the
vehicle. The air flow path is distributed transversely to the length of
the vehicle for transporting heat convectively away from the vehicle.