The base zone development standards in Subtitle D, Chapter 2 shall apply to the R-1A/TS and R-1B/TS zones except as specifically modified by this chapter. In the event of a conflict between the provisions of this chapter and other regulations of this title, the provisions of this chapter shall control.
In addition to the purposes of the R-1 zones, the purposes of the Tree and Slope Protection Residential House (R-1A/TS and R-1B/TS) zones are to:
The R-1A/TS and R-1B/TS zones shall be mapped in residential neighborhoods that are located at the edge of stream beds or public open spaces and that have a significant quantity of steep slopes, stands of mature trees, and undeveloped lots and parcels subject to potential terrain alteration and tree removal. It is not suitable for mapping in neighborhoods where nearly all lots are already developed on a rectangular grid system and the existing mature trees are either yard trees or street trees.
D.C. Mun. Regs. tit. 11, r. 11-D300