The coating booth for elements to be coated (3) of considerable length, has a triangular plan schematically identified by a first, a second and a third vertex (A, B and C), within which a conveyor line (2) enters the side (BC) having the second and third vertices (B and C) as the endpoints, completing a path that brings the elements to be coated (3) toward the first vertex (A), to then return and have the elements to be coated (3) exit from the side (BC) in a substantially symmetrical position with respect to the first vertex (A).