36 CFR § 910.14 - Historic preservation.
(a) The Development Area is located almost entirely within the Pennsylvania Avenue National Historic Site, which was established to preserve the exceptional values of Pennsylvania Avenue and its environs in commemorating or illustrating the history of the United States. The Pennsylvania Avenue Area achieves national historic significance because of both its ceremonial role in the life of the nation and its social and economic role in the life of the residents of Washington for more than a century.
(b) The Historic Preservation Plan of the Corporation sets forth the adopted policy of the Corporation on historic preservation and development within the Development Area must be consistent with this policy.
(c) New construction adjacent to historic structures will be required to take into account the qualities of the adjacent structures (with regard to height, scale, proportion, rhythm, texture, materials, architectural detail, and the amount of variety among the structures with respect to these qualities as well as style and date of erection) to ensure that these structures maintain their historic or architectural integrity, but will not necessarily be required to conform to them.
(d) Wholly new construction and new construction in conjunction with preservation will, where appropriate, take into account the historic buildings to remain, aiming for the highest quality of contemporary design, consistent with the goals and objectives of the Historic Preservation Plan.