La. Stat. tit. 33 § 5055
Within cities having a population of more than three hundred thousand inhabitants in order that the architectural style of buildings and structures situated in certain designated localities or boundaries or between certain street or road intersections, and fronting on designated public streets, boulevards, roads or public or private roads and places, may be preserved in their integrity and not impaired, changed, altered or destroyed, it shall be lawful for the owners of such real estate and others having rights therein, or if the owners of same or others having rights therein, be minors or interdicts, for their tutors, curators or administrators, to enter into written agreements, to be duly acknowledged according to law before any notary public, or by authentic acts, whereby they mutually agree to preserve in their integrity and not to impair, change, alter or destroy the architectural style or distinctive features of their buildings or the fronts thereof, situated or located as described in the agreements, so far as the same relate to the style, appearance, texture of materials and other distinctive features thereof, for the term of years to be specified in the contracts.
La. R.S. § 33:5055