Abstract: Apparatus for climatizing a building comprising means including elements of a structural frame adapted to provide a portion of a facade for such building, at least a portion of said elements being hollow, said hollow elements being formed to provide for movement therethrough of fluid for supplying heat thereto or extracting heat therefrom, means for the delivery of fluid to and for the direction of fluid from said hollow elements, and said hollow elements being arranged for the mounting of facade elements to extend in bridging relation thereto and to be conditioned thereby.